draft-ietf-tsvwg-addip-sctp-08.txt   draft-ietf-tsvwg-addip-sctp-09.txt 
Network Working Group R. Stewart Network Working Group R. Stewart
Internet-Draft M. Ramalho Internet-Draft M. Ramalho
Expires: March 24, 2004 Cisco Systems, Inc. Expires: December 9, 2004 Cisco Systems, Inc.
Q. Xie Q. Xie
Motorola, Inc. Motorola, Inc.
M. Tuexen M. Tuexen
Univ. of Applied Sciences Muenster Univ. of Applied Sciences Muenster
I. Rytina
M. Belinchon
Ericsson
P. Conrad P. Conrad
Temple University University of Delaware
September 24, 2003 June 10, 2004
Stream Control Transmission Protocol (SCTP) Dynamic Address Stream Control Transmission Protocol (SCTP) Dynamic Address
Reconfiguration Reconfiguration
draft-ietf-tsvwg-addip-sctp-08.txt draft-ietf-tsvwg-addip-sctp-09.txt
Status of this Memo Status of this Memo
This document is an Internet-Draft and is in full conformance with By submitting this Internet-Draft, I certify that any applicable
all provisions of Section 10 of RFC2026. patent or other IPR claims of which I am aware have been disclosed,
and any of which I become aware will be disclosed, in accordance with
RFC 3668.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other Task Force (IETF), its areas, and its working groups. Note that
groups may also distribute working documents as Internet-Drafts. other groups may also distribute working documents as
Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at http:// The list of current Internet-Drafts can be accessed at
www.ietf.org/ietf/1id-abstracts.txt. http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
This Internet-Draft will expire on March 24, 2004. This Internet-Draft will expire on December 9, 2004.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved. Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract Abstract
This document describes extensions to the Stream Control Transmission This document describes extensions to the Stream Control Transmission
Protocol (SCTP) [RFC2960] that provides a method to reconfigure IP Protocol (SCTP) [RFC2960] that provides a method to reconfigure IP
address information on an existing association. address information on an existing association.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Additional Chunks and Parameters . . . . . . . . . . . . . . 5 3. Additional Chunks and Parameters . . . . . . . . . . . . . . . 5
3.1 New Chunk Types . . . . . . . . . . . . . . . . . . . . . . 5 3.1 New Chunk Types . . . . . . . . . . . . . . . . . . . . . 5
3.1.1 Address Configuration Change Chunk (ASCONF) . . . . . . . . 5 3.1.1 Address Configuration Change Chunk (ASCONF) . . . . . 5
3.1.2 Address Configuration Acknowledgment Chunk (ASCONF-ACK) . . 6 3.1.2 Address Configuration Acknowledgment Chunk
3.2 New Parameter Types . . . . . . . . . . . . . . . . . . . . 7 (ASCONF-ACK) . . . . . . . . . . . . . . . . . . . . . 6
3.2.1 Add IP Address . . . . . . . . . . . . . . . . . . . . . . . 8 3.2 New Parameter Types . . . . . . . . . . . . . . . . . . . 7
3.2.2 Delete IP Address . . . . . . . . . . . . . . . . . . . . . 9 3.2.1 Add IP Address . . . . . . . . . . . . . . . . . . . . 8
3.2.3 Error Cause Indication . . . . . . . . . . . . . . . . . . . 10 3.2.2 Delete IP Address . . . . . . . . . . . . . . . . . . 9
3.2.4 Set Primary IP Address . . . . . . . . . . . . . . . . . . . 10 3.2.3 Error Cause Indication . . . . . . . . . . . . . . . . 10
3.2.5 Success Indication . . . . . . . . . . . . . . . . . . . . . 11 3.2.4 Set Primary IP Address . . . . . . . . . . . . . . . . 11
3.2.6 Adaptation Layer Indication . . . . . . . . . . . . . . . . 12 3.2.5 Success Indication . . . . . . . . . . . . . . . . . . 12
3.3 New Error Causes . . . . . . . . . . . . . . . . . . . . . . 13 3.2.6 Adaptation Layer Indication . . . . . . . . . . . . . 12
3.3.1 Error Cause: Request to Delete Last Remaining IP Address . . 13 3.3 New Error Causes . . . . . . . . . . . . . . . . . . . . . 13
3.3.2 Error Cause: Operation Refused Due to Resource Shortage . . 14 3.3.1 Error Cause: Request to Delete Last Remaining IP
3.3.3 Error Cause: Request to Delete Source IP Address . . . . . . 15 Address . . . . . . . . . . . . . . . . . . . . . . . 13
3.3.2 Error Cause: Operation Refused Due to Resource
Shortage . . . . . . . . . . . . . . . . . . . . . . . 14
3.3.3 Error Cause: Request to Delete Source IP Address . . . 15
3.3.4 Error Cause: Association Aborted due to illegal 3.3.4 Error Cause: Association Aborted due to illegal
ASCONF-ACK . . . . . . . . . . . . . . . . . . . . . . . . . 15 ASCONF-ACK . . . . . . . . . . . . . . . . . . . . . . 16
3.3.5 Error Cause: Request refused - no authorization. . . . . . . 16 3.3.5 Error Cause: Request refused - no authorization. . . . 16
4. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 17 4. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1 ASCONF Chunk Procedures . . . . . . . . . . . . . . . . . . 17 4.1 ASCONF Chunk Procedures . . . . . . . . . . . . . . . . . 18
4.1.1 Congestion Control of ASCONF Chunks . . . . . . . . . . . . 18 4.1.1 Congestion Control of ASCONF Chunks . . . . . . . . . 19
4.2 Upon reception of an ASCONF Chunk. . . . . . . . . . . . . . 19 4.2 Upon reception of an ASCONF Chunk. . . . . . . . . . . . . 20
4.3 General rules for address manipulation . . . . . . . . . . . 21 4.3 General rules for address manipulation . . . . . . . . . . 22
4.3.1 A special case for OOTB ABORT chunks . . . . . . . . . . . . 25 4.3.1 A special case for OOTB ABORT chunks . . . . . . . . . 25
4.3.2 A special case for changing an address. . . . . . . . . . . 25 4.3.2 A special case for changing an address. . . . . . . . 25
4.4 Setting of the primary address . . . . . . . . . . . . . . . 26 4.4 Setting of the primary address . . . . . . . . . . . . . . 26
5. Security Considerations . . . . . . . . . . . . . . . . . . 27 5. Security Considerations . . . . . . . . . . . . . . . . . . . 27
6. IANA considerations . . . . . . . . . . . . . . . . . . . . 28 6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 28
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 29 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 29
References . . . . . . . . . . . . . . . . . . . . . . . . . 30 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 30 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 29
A. Abstract Address Handling . . . . . . . . . . . . . . . . . 33 A. Abstract Address Handling . . . . . . . . . . . . . . . . . . 31
A.1 General remarks . . . . . . . . . . . . . . . . . . . . . . 33 A.1 General remarks . . . . . . . . . . . . . . . . . . . . . 31
A.2 Generalized endpoints . . . . . . . . . . . . . . . . . . . 33 A.2 Generalized endpoints . . . . . . . . . . . . . . . . . . 31
A.3 Associations . . . . . . . . . . . . . . . . . . . . . . . . 34 A.3 Associations . . . . . . . . . . . . . . . . . . . . . . . 32
A.4 Relationship with RFC 2960 . . . . . . . . . . . . . . . . . 35 A.4 Relationship with RFC 2960 . . . . . . . . . . . . . . . . 32
A.5 Rules for address manipulation . . . . . . . . . . . . . . . 35 A.5 Rules for address manipulation . . . . . . . . . . . . . . 33
Intellectual Property and Copyright Statements . . . . . . . 36 Intellectual Property and Copyright Statements . . . . . . . . 34
1. Introduction 1. Introduction
To extend the utility and application scenarios of SCTP, this To extend the utility and application scenarios of SCTP, this
document introduces optional extensions that provide SCTP with the document introduces optional extensions that provide SCTP with the
ability to: ability to:
1. reconfigure IP address information on an existing association. 1. reconfigure IP address information on an existing association.
2. set the remote primary path. 2. set the remote primary path.
3. exchange adaptation layer information during association setup. 3. exchange adaptation layer information during association setup.
These extensions enable SCTP to be utilized in the following These extensions enable SCTP to be utilized in the following
applications: applications:
1. For computational or networking platforms that allow addition/ 1. For computational or networking platforms that allow addition/
removal of physical interface cards this feature can provide a removal of physical interface cards this feature can provide a
graceful method to add to the interfaces of an existing graceful method to add to the interfaces of an existing
association. For IPv6 this feature allows renumbering of existing association. For IPv6 this feature allows renumbering of
associations. existing associations.
2. This provides a method for an endpoint to request that its peer 2. This provides a method for an endpoint to request that its peer
set its primary destination address. This can be useful when an set its primary destination address. This can be useful when an
address is about to be deleted, or when an endpoint has some address is about to be deleted, or when an endpoint has some
predetermined knowledge about which is the preferred address to predetermined knowledge about which is the preferred address to
receive SCTP packets upon. receive SCTP packets upon.
3. This feature can be used to extend the usability of SCTP without 3. This feature can be used to extend the usability of SCTP without
modifying it by allowing endpoints to exchange some information modifying it by allowing endpoints to exchange some information
during association setup. during association setup.
2. Conventions 2. Conventions
The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD, The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD,
SHOULD NOT, RECOMMENDED, NOT RECOMMENDED, MAY, and OPTIONAL, when SHOULD NOT, RECOMMENDED, NOT RECOMMENDED, MAY, and OPTIONAL, when
they appear in this document, are to be interpreted as described in they appear in this document, are to be interpreted as described in
RFC2119 [2]. RFC2119 [2].
skipping to change at page 5, line 36 skipping to change at page 5, line 34
Chunk Type Chunk Name Chunk Type Chunk Name
-------------------------------------------------------------- --------------------------------------------------------------
0xC1 Address Configuration Change Chunk (ASCONF) 0xC1 Address Configuration Change Chunk (ASCONF)
0x80 Address Configuration Acknowledgment (ASCONF-ACK) 0x80 Address Configuration Acknowledgment (ASCONF-ACK)
Table 1: Address Configuration Chunks Table 1: Address Configuration Chunks
It should be noted that the ASCONF Chunk format requires the receiver It should be noted that the ASCONF Chunk format requires the receiver
to report to the sender if it does not understand the ASCONF Chunk. to report to the sender if it does not understand the ASCONF Chunk.
This is accomplished by setting the upper bits in the chunk type as This is accomplished by setting the upper bits in the chunk type as
described in RFC2960 [5] section 3.2. Note that the upper two bits in described in RFC2960 [6] section 3.2. Note that the upper two bits
the ASCONF Chunk are set to one. As defined in RFC2960 [5] section in the ASCONF Chunk are set to one. As defined in RFC2960 [6]
3.2, setting these upper bits in this manner will cause the receiver section 3.2, setting these upper bits in this manner will cause the
that does not understand this chunk to skip the chunk and continue receiver that does not understand this chunk to skip the chunk and
processing, but report in an Operation Error Chunk using the continue processing, but report in an Operation Error Chunk using the
'Unrecognized Chunk Type' cause of error. 'Unrecognized Chunk Type' cause of error.
3.1.1 Address Configuration Change Chunk (ASCONF) 3.1.1 Address Configuration Change Chunk (ASCONF)
This chunk is used to communicate to the remote endpoint one of the This chunk is used to communicate to the remote endpoint one of the
configuration change requests that MUST be acknowledged. The configuration change requests that MUST be acknowledged. The
information carried in the ASCONF Chunk uses the form of a information carried in the ASCONF Chunk uses the form of a
Type-Length-Value (TLV), as described in "3.2.1 Optional/ Type-Length-Value (TLV), as described in "3.2.1 Optional/
Variable-length Parameter Format" in RFC2960 [5], forall variable Variable-length Parameter Format" in RFC2960 [6], for all variable
parameters. parameters.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 0xC1 | Chunk Flags | Chunk Length | | Type = 0xC1 | Chunk Flags | Chunk Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Serial Number | | Serial Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Parameter | | Address Parameter |
skipping to change at page 6, line 23 skipping to change at page 6, line 25
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\ \ \ \
/ .... / / .... /
\ \ \ \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF Parameter #N | | ASCONF Parameter #N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Serial Number : 32 bits (unsigned integer) Serial Number : 32 bits (unsigned integer)
This value represents a Serial Number for the ASCONF Chunk. The valid This value represents a Serial Number for the ASCONF Chunk. The
range of Serial Number is from 0 to 4294967295 (2**32 - 1). Serial valid range of Serial Number is from 0 to 4294967295 (2**32 - 1).
Numbers wrap back to 0 after reaching 4294967295. Serial Numbers wrap back to 0 after reaching 4294967295.
Address Parameter : 8 or 20 bytes (depending on type) Address Parameter : 8 or 20 bytes (depending on type)
This field contains an address parameter, either IPv6 or IPv4, from This field contains an address parameter, either IPv6 or IPv4, from
RFC2960 [5]. The address is an address of the sender of the ASCONF RFC2960 [6]. The address is an address of the sender of the ASCONF
chunk, the address MUST be considered part of the association by the chunk, the address MUST be considered part of the association by the
peer endpoint (the receiver of the ASCONF chunk). This field may be peer endpoint (the receiver of the ASCONF chunk). This field may be
used by the receiver of the ASCONF to help in finding the used by the receiver of the ASCONF to help in finding the
association. This parameter MUST be present in every ASCONF message association. This parameter MUST be present in every ASCONF message
i.e. it is a mandatory TLV parameter. i.e. it is a mandatory TLV parameter.
Note the host name address parameter is NOT allowed and MUST be Note the host name address parameter is NOT allowed and MUST be
ignored if received in any ASCONF message. ignored if received in any ASCONF message.
ASCONF Parameter: TLV format ASCONF Parameter: TLV format
skipping to change at page 7, line 39 skipping to change at page 7, line 39
The ASCONF Parameter Response is used in the ASCONF-ACK to report The ASCONF Parameter Response is used in the ASCONF-ACK to report
status of ASCONF processing. By default, if a responding endpoint status of ASCONF processing. By default, if a responding endpoint
does not include any Error Cause, a success is indicated. Thus a does not include any Error Cause, a success is indicated. Thus a
sender of an ASCONF-ACK MAY indicate complete success of all TLVs in sender of an ASCONF-ACK MAY indicate complete success of all TLVs in
an ASCONF by returning only the Chunk Type, Chunk Flags, Chunk Length an ASCONF by returning only the Chunk Type, Chunk Flags, Chunk Length
(set to 8) and the Serial Number. (set to 8) and the Serial Number.
3.2 New Parameter Types 3.2 New Parameter Types
The six new parameters added follow the format defined in section The six new parameters added follow the format defined in section
3.2.1 of RFC2960 [5]. Table 2 and 3 describes the parameters. 3.2.1 of RFC2960 [6]. Table 2 and 3 describes the parameters.
Address Configuration Parameters Parameter Type Address Configuration Parameters Parameter Type
------------------------------------------------- -------------------------------------------------
Set Primary Address 0xC004 Set Primary Address 0xC004
Adaption Layer Indication 0xC006 Adaption Layer Indication 0xC006
Table 2: Parameters that can be used in INIT/INIT-ACK chunk Table 2: Parameters that can be used in INIT/INIT-ACK chunk
Address Configuration Parameters Parameter Type Address Configuration Parameters Parameter Type
------------------------------------------------- -------------------------------------------------
Add IP Address 0xC001 Add IP Address 0xC001
Delete IP Address 0xC002 Delete IP Address 0xC002
Set Primary Address 0xC004 Set Primary Address 0xC004
Table 2: Parameters used in ASCONF Parameter Table 2: Parameters used in ASCONF Parameter
Address Configuration Parameters Parameter Type Address Configuration Parameters Parameter Type
------------------------------------------------- -------------------------------------------------
skipping to change at page 8, line 15 skipping to change at page 8, line 19
Table 2: Parameters used in ASCONF Parameter Table 2: Parameters used in ASCONF Parameter
Address Configuration Parameters Parameter Type Address Configuration Parameters Parameter Type
------------------------------------------------- -------------------------------------------------
Error Cause Indication 0xC003 Error Cause Indication 0xC003
Success Indication 0xC005 Success Indication 0xC005
Table 3: Parameters used in ASCONF Parameter Response Table 3: Parameters used in ASCONF Parameter Response
Any parameter that appears where it is not allowed (for example a
0xC002 parameter appearing within an INIT or INIT-ACK) MAY be
responded to with an ABORT by the receiver of the invalid parameter.
3.2.1 Add IP Address 3.2.1 Add IP Address
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 0xC001 | Length = Variable | | Type = 0xC001 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Request Correlation ID | | ASCONF-Request Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Parameter | | Address Parameter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ASCONF-Request Correlation ID: 32 bits ASCONF-Request Correlation ID: 32 bits
This is an opaque integer assigned by the sender to identify each This is an opaque integer assigned by the sender to identify each
request parameter. It is in host byte order and is only meaningful to request parameter. It is in host byte order and is only meaningful
the sender. The receiver of the ASCONF Chunk will copy this 32 bit to the sender. The receiver of the ASCONF Chunk will copy this 32
value into the ASCONF Response Correlation ID field of the ASCONF-ACK bit value into the ASCONF Response Correlation ID field of the
response parameter. The sender of the ASCONF can use this same value ASCONF-ACK response parameter. The sender of the ASCONF can use this
in the ASCONF-ACK to find which request the response is for. same value in the ASCONF-ACK to find which request the response is
for.
Address Parameter: TLV Address Parameter: TLV
This field contains an IPv4 or IPv6 address parameter as described in This field contains an IPv4 or IPv6 address parameter as described in
3.3.2.1 of RFC2960 [5]. The complete TLV is wrapped within this 3.3.2.1 of RFC2960 [6]. The complete TLV is wrapped within this
parameter. It informs the receiver that the address specified is to parameter. It informs the receiver that the address specified is to
be added to the existing association. be added to the existing association.
An example TLV requesting that the IPv4 address 10.1.1.1 be added to An example TLV requesting that the IPv4 address 10.1.1.1 be added to
the association would look as follows: the association would look as follows:
+--------------------------------+ +--------------------------------+
| Type=0xC001 | Length = 16 | | Type=0xC001 | Length = 16 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023474 | | C-ID = 0x01023474 |
skipping to change at page 9, line 31 skipping to change at page 9, line 39
| Type =0xC002 | Length = Variable | | Type =0xC002 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Request Correlation ID | | ASCONF-Request Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Parameter | | Address Parameter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ASCONF-Request Correlation ID: 32 bits ASCONF-Request Correlation ID: 32 bits
This is an opaque integer assigned by the sender to identify each This is an opaque integer assigned by the sender to identify each
request parameter. It is in host byte order and is only meaningful to request parameter. It is in host byte order and is only meaningful
the sender. The receiver of the ASCONF Chunk will copy this 32 bit to the sender. The receiver of the ASCONF Chunk will copy this 32
value into the ASCONF Response Correlation ID field of the ASCONF-ACK bit value into the ASCONF Response Correlation ID field of the
response parameter. The sender of the ASCONF can use this same value ASCONF-ACK response parameter. The sender of the ASCONF can use this
in the ASCONF-ACK to find which request the response is for. same value in the ASCONF-ACK to find which request the response is
for.
Address Parameter: TLV Address Parameter: TLV
This field contains an IPv4 or IPv6 address parameter as described in This field contains an IPv4 or IPv6 address parameter as described in
3.3.2.1 of RFC2960 [5]. The complete TLV is wrapped within this 3.3.2.1 of RFC2960 [6]. The complete TLV is wrapped within this
parameter. It informs the receiver that the address specified is to parameter. It informs the receiver that the address specified is to
be removed from the existing association. be removed from the existing association.
An example TLV deleting the IPv4 address 10.1.1.1 from an existing An example TLV deleting the IPv4 address 10.1.1.1 from an existing
association would look as follows: association would look as follows:
+--------------------------------+ +--------------------------------+
| Type=0xC002 | Length = 16 | | Type=0xC002 | Length = 16 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023476 | | C-ID = 0x01023476 |
skipping to change at page 10, line 29 skipping to change at page 10, line 38
| Type = 0xC003 | Length = Variable | | Type = 0xC003 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Response Correlation ID | | ASCONF-Response Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Cause(s) or Return Info on Success | | Error Cause(s) or Return Info on Success |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ASCONF-Response Correlation ID: 32 bits ASCONF-Response Correlation ID: 32 bits
This is an opaque integer assigned by the sender to identify each This is an opaque integer assigned by the sender to identify each
request parameter. The receiver of the ASCONF Chunk will copy this 32 request parameter. The receiver of the ASCONF Chunk will copy this
bit value from the ASCONF-Request Correlation ID into the ASCONF 32 bit value from the ASCONF-Request Correlation ID into the ASCONF
Response Correlation ID field so the peer can easily correlate the Response Correlation ID field so the peer can easily correlate the
request to this response. request to this response.
Error Cause(s): TLV(s) Error Cause(s): TLV(s)
When reporting an error this response parameter is used to wrap one When reporting an error this response parameter is used to wrap one
or more standard error causes normally found within an SCTP or more standard error causes normally found within an SCTP
Operational Error or SCTP Abort (as defined in RFC2960 [5]). The Operational Error or SCTP Abort (as defined in RFC2960 [6]). The
Error Cause(s) follow the format defined in section 3.3.10 of RFC2960 Error Cause(s) follow the format defined in section 3.3.10 of RFC2960
[5]. [6].
Valid Chunk Appearance Valid Chunk Appearance
The Error Cause Indication parameter may only appear in the The Error Cause Indication parameter may only appear in the
ASCONF-ACK chunk type. ASCONF-ACK chunk type.
3.2.4 Set Primary IP Address 3.2.4 Set Primary IP Address
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type =0xC004 | Length = Variable | | Type =0xC004 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 11, line 14 skipping to change at page 11, line 22
| Type =0xC004 | Length = Variable | | Type =0xC004 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Request Correlation ID | | ASCONF-Request Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Parameter | | Address Parameter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ASCONF-Request Correlation ID: 32 bits ASCONF-Request Correlation ID: 32 bits
This is an opaque integer assigned by the sender to identify each This is an opaque integer assigned by the sender to identify each
request parameter. It is in host byte order and is only meaningful to request parameter. It is in host byte order and is only meaningful
the sender. The receiver of the ASCONF Chunk will copy this 32 bit to the sender. The receiver of the ASCONF Chunk will copy this 32
value into the ASCONF Response Correlation ID field of the ASCONF-ACK bit value into the ASCONF Response Correlation ID field of the
response parameter. The sender of the ASCONF can use this same value ASCONF-ACK response parameter. The sender of the ASCONF can use this
in the ASCONF-ACK to find which request the response is for. same value in the ASCONF-ACK to find which request the response is
for.
Address Parameter: TLV Address Parameter: TLV
This field contains an IPv4 or IPv6 address parameter as described in This field contains an IPv4 or IPv6 address parameter as described in
3.3.2.1 of RFC2960 [5]. The complete TLV is wrapped within this 3.3.2.1 of RFC2960 [6]. The complete TLV is wrapped within this
parameter. It requests the receiver to mark the specified address as parameter. It requests the receiver to mark the specified address as
the primary address to send data to (see section 5.1.2 of RFC2960 the primary address to send data to (see section 5.1.2 of RFC2960
[5]). The receiver MAY mark this as its primary upon receiving this [6]). The receiver MAY mark this as its primary upon receiving this
request. request.
An example TLV requesting that the IPv4 address 10.1.1.1 be made the An example TLV requesting that the IPv4 address 10.1.1.1 be made the
primary destination address would look as follows: primary destination address would look as follows:
+--------------------------------+ +--------------------------------+
| Type=0xC004 | Length = 16 | | Type=0xC004 | Length = 16 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023479 | | C-ID = 0x01023479 |
+--------------------------------+ +--------------------------------+
skipping to change at page 11, line 43 skipping to change at page 12, line 4
| Type=0xC004 | Length = 16 | | Type=0xC004 | Length = 16 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023479 | | C-ID = 0x01023479 |
+--------------------------------+ +--------------------------------+
| Type=5 | Length = 8 | | Type=5 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0a010101 | | Value=0x0a010101 |
+----------------+---------------+ +----------------+---------------+
Valid Chunk Appearance Valid Chunk Appearance
The Set Primary IP Address parameter may appear in the ASCONF Chunk, The Set Primary IP Address parameter may appear in the ASCONF Chunk,
the INIT, or the INIT-ACK chunk type. The inclusion of this parameter the INIT, or the INIT-ACK chunk type. The inclusion of this
in the INIT or INIT-ACK can be used to indicate an initial preference parameter in the INIT or INIT-ACK can be used to indicate an initial
of primary address. preference of primary address.
3.2.5 Success Indication 3.2.5 Success Indication
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 0xC005 | Length = 8 | | Type = 0xC005 | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Response Correlation ID | | ASCONF-Response Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 12, line 24 skipping to change at page 12, line 32
returning only the Chunk Type, Chunk Flags, Chunk Length (set to 8) returning only the Chunk Type, Chunk Flags, Chunk Length (set to 8)
and the Serial Number. and the Serial Number.
The responding endpoint MAY also choose to explicitly report a The responding endpoint MAY also choose to explicitly report a
success for a requested TLV, by returning a success report ASCONF success for a requested TLV, by returning a success report ASCONF
Parameter Response. Parameter Response.
ASCONF-Response Correlation ID: 32 bits ASCONF-Response Correlation ID: 32 bits
This is an opaque integer assigned by the sender to identify each This is an opaque integer assigned by the sender to identify each
request parameter. The receiver of the ASCONF Chunk will copy this 32 request parameter. The receiver of the ASCONF Chunk will copy this
bit value from the ASCONF-Request Correlation ID into the ASCONF 32 bit value from the ASCONF-Request Correlation ID into the ASCONF
Response Correlation ID field so the peer can easily correlate the Response Correlation ID field so the peer can easily correlate the
request to this response. request to this response.
Valid Chunk Appearance Valid Chunk Appearance
The Success Indication parameter may only appear in the ASCONF-ACK The Success Indication parameter may only appear in the ASCONF-ACK
chunk type. chunk type.
3.2.6 Adaptation Layer Indication 3.2.6 Adaptation Layer Indication
skipping to change at page 15, line 11 skipping to change at page 15, line 26
| Type=0x0005 | Length = 8 | | Type=0x0005 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0A010101 | | Value=0x0A010101 |
+----------------+---------------+ +----------------+---------------+
3.3.3 Error Cause: Request to Delete Source IP Address 3.3.3 Error Cause: Request to Delete Source IP Address
Cause of error Cause of error
Request to Delete Source IP Address: The receiver of this error sent Request to Delete Source IP Address: The receiver of this error sent
a request to delete the source IP address of the ASCONF message. This a request to delete the source IP address of the ASCONF message.
error indicates that the request is rejected. This error indicates that the request is rejected.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cause Code=0x0102 | Cause Length=Variable | | Cause Code=0x0102 | Cause Length=Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\ TLV-Copied-From-ASCONF / \ TLV-Copied-From-ASCONF /
/ \ / \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 16, line 5 skipping to change at page 16, line 31
IMPLEMENTATION NOTE: It is unlikely that an endpoint would source a IMPLEMENTATION NOTE: It is unlikely that an endpoint would source a
packet from the address being deleted, unless the endpoint does not packet from the address being deleted, unless the endpoint does not
do proper source address selection. do proper source address selection.
3.3.4 Error Cause: Association Aborted due to illegal ASCONF-ACK 3.3.4 Error Cause: Association Aborted due to illegal ASCONF-ACK
This error is to be included in an ABORT that is generated due to the This error is to be included in an ABORT that is generated due to the
reception of an ASCONF-ACK that was not expected but is larger than reception of an ASCONF-ACK that was not expected but is larger than
the current sequence number (see Section 4.3 Rule D0 ). Note that a the current sequence number (see Section 4.3 Rule D0 ). Note that a
sequence number is larger than the last acked sequence number if it sequence number is larger than the last acked sequence number if it
is either the next sequence or no more than 2^^31 greater than the is either the next sequence or no more than 2^^31-1 greater than the
current sequence number. current sequence number.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cause Code=0x0103 | Cause Length=4 | | Cause Code=0x0103 | Cause Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3.3.5 Error Cause: Request refused - no authorization. 3.3.5 Error Cause: Request refused - no authorization.
skipping to change at page 17, line 19 skipping to change at page 18, line 19
4.1 ASCONF Chunk Procedures 4.1 ASCONF Chunk Procedures
When an endpoint has an ASCONF signaled change to be sent to the When an endpoint has an ASCONF signaled change to be sent to the
remote endpoint it should do the following: remote endpoint it should do the following:
A1) Create an ASCONF Chunk as defined in Section 3.1.1. The chunk A1) Create an ASCONF Chunk as defined in Section 3.1.1. The chunk
should contain all of the TLV(s) of information necessary to be should contain all of the TLV(s) of information necessary to be
sent to the remote endpoint, and unique correlation identities for sent to the remote endpoint, and unique correlation identities for
each request. each request.
A2) A serial number should be assigned to the Chunk. The serial A2) A serial number should be assigned to the Chunk. The serial
number should be a monotonically increasing number. The serial number should be a monotonically increasing number. The serial
number SHOULD be initialized at the start of the association to number MUST be initialized at the start of the association to the
the same value as the Initial TSN and every time a new ASCONF same value as the Initial TSN and every time a new ASCONF chunk is
chunk is created it is incremented by one after assigning the created it is incremented by one after assigning the serial number
serial number to the newly created chunk . to the newly created chunk .
A3) If no ASCONF Chunk is outstanding (un-acknowledged) with the A3) If no ASCONF Chunk is outstanding (un-acknowledged) with the
remote peer, send the chunk. remote peer, send the chunk.
A4) Start a T-4 RTO timer, using the RTO value of the selected A4) Start a T-4 RTO timer, using the RTO value of the selected
destination address (normally the primary path; see RFC2960 [5] destination address (normally the primary path; see RFC2960 [6]
section 6.4 for details). section 6.4 for details).
A5) When the ASCONF-ACK that acknowledges the serial number last sent A5) When the ASCONF-ACK that acknowledges the serial number last sent
arrives, stop the T-4 RTO timer, and clear the appropriate arrives, stop the T-4 RTO timer, and clear the appropriate
association and destination error counters as defined in RFC2960 association and destination error counters as defined in RFC2960
[5] section 8.1 and 8.2. [6] section 8.1 and 8.2.
A6) Process all of the TLVs within the ASCONF-ACK to find out A6) Process all of the TLVs within the ASCONF-ACK to find out
particular status information returned to the various requests particular status information returned to the various requests
that were sent. Use the Correlation IDs to correlate the request that were sent. Use the Correlation IDs to correlate the request
and the responses. and the responses.
A7) If an error response is received for a TLV parameter, all TLVs A7) If an error response is received for a TLV parameter, all TLVs
with no response before the failed TLV are considered successful with no response before the failed TLV are considered successful
if not reported. All TLVs after the failed response are if not reported. All TLVs after the failed response are
considered unsuccessful unless a specific success indication is considered unsuccessful unless a specific success indication is
present for the parameter. present for the parameter.
A8) If there is no response(s) to specific TLV parameter(s), and no A8) If there is no response(s) to specific TLV parameter(s), and no
failures are indicated, then all request(s) are considered failures are indicated, then all request(s) are considered
successful. successful.
A9) If the peer responds to an ASCONF with an ERROR chunk reporting A9) If the peer responds to an ASCONF with an ERROR chunk reporting
that it did not recognized the ASCONF chunk type, the sender of that it did not recognize the ASCONF chunk type, the sender of the
the ASCONF MUST NOT send any further ASCONF chunks and MUST stop ASCONF MUST NOT send any further ASCONF chunks and MUST stop its
its T-4 timer. T-4 timer.
If the T-4 RTO timer expires the endpoint should do the following: If the T-4 RTO timer expires the endpoint should do the following:
B1) Increment the error counters and perform path failure detection B1) Increment the error counters and perform path failure detection
on the appropriate destination address as defined in RFC2960 [5] on the appropriate destination address as defined in RFC2960 [6]
section 8.1 and 8.2. section 8.1 and 8.2.
B2) Increment the association error counters and perform endpoint B2) Increment the association error counters and perform endpoint
failure detection on the association as defined in RFC2960 [5] failure detection on the association as defined in RFC2960 [6]
section 8.1 and 8.2. section 8.1 and 8.2.
B3) Back-off the destination address RTO value to which the ASCONF B3) Back-off the destination address RTO value to which the ASCONF
chunk was sent by doubling the RTO timer value. chunk was sent by doubling the RTO timer value.
Note: The RTO value is used in the setting of all timer types for Note: The RTO value is used in the setting of all timer types for
SCTP. Each destination address has a single RTO estimate. SCTP. Each destination address has a single RTO estimate.
B4) Re-transmit the ASCONF Chunk last sent and if possible choose an B4) Re-transmit the ASCONF Chunk last sent and if possible choose an
alternate destination address (please refer to RFC2960 [5] section alternate destination address (please refer to RFC2960 [6] section
6.4.1). An endpoint MUST NOT add new parameters to this chunk, it 6.4.1). An endpoint MUST NOT add new parameters to this chunk, it
MUST be the same (including its serial number) as the last ASCONF MUST be the same (including its serial number) as the last ASCONF
sent. sent.
B5) Restart the T-4 RTO timer. Note that if a different destination B5) Restart the T-4 RTO timer. Note that if a different destination
is selected, then the RTO used will be that of the new destination is selected, then the RTO used will be that of the new destination
address. address.
Note: the total number of re-transmissions is limited by B2 above. If Note: the total number of re-transmissions is limited by B2 above.
the maximum is reached, the association will fail and enter into the If the maximum is reached, the association will fail and enter into
CLOSED state (see RFC2960 [5] section 6.4.1 for details). the CLOSED state (see RFC2960 [6] section 6.4.1 for details).
4.1.1 Congestion Control of ASCONF Chunks 4.1.1 Congestion Control of ASCONF Chunks
In defining the ASCONF Chunk transfer procedures, it is essential In defining the ASCONF Chunk transfer procedures, it is essential
that these transfers MUST NOT cause congestion within the network. To that these transfers MUST NOT cause congestion within the network.
achieve this, we place these restrictions on the transfer of ASCONF To achieve this, we place these restrictions on the transfer of
Chunks: ASCONF Chunks:
R1) One and only one ASCONF Chunk MAY be in transit and R1) One and only one ASCONF Chunk MAY be in transit and
unacknowledged at any one time. If a sender, after sending an unacknowledged at any one time. If a sender, after sending an
ASCONF chunk, decides it needs to transfer another ASCONF Chunk, ASCONF chunk, decides it needs to transfer another ASCONF Chunk,
it MUST wait until the ASCONF-ACK Chunk returns from the previous it MUST wait until the ASCONF-ACK Chunk returns from the previous
ASCONF Chunk before sending a subsequent ASCONF. Note this ASCONF Chunk before sending a subsequent ASCONF. Note this
restriction binds each side, so at any time two ASCONF may be restriction binds each side, so at any time two ASCONF may be
in-transit on any given association (one sent from each endpoint). in-transit on any given association (one sent from each endpoint).
R2) An ASCONF may be bundled with any other chunk type (except other R2) An ASCONF may be bundled with any other chunk type (except other
ASCONF Chunks). ASCONF Chunks).
R3) An ASCONF-ACK may be bundled with any other chunk type except R3) An ASCONF-ACK may be bundled with any other chunk type except
other ASCONF-ACKs. other ASCONF-ACKs.
R4) Both ASCONF and ASCONF-ACK chunks MUST NOT be sent in any SCTP R4) Both ASCONF and ASCONF-ACK chunks MUST NOT be sent in any SCTP
state except ESTABLISHED. state except ESTABLISHED, SHUTDOWN-PENDING, SHUTDOWN-RECEIVED and
SHUTDOWN-SENT.
R5) An ASCONF MUST NOT be larger than the path MTU of the R5) An ASCONF MUST NOT be larger than the path MTU of the
destination. destination.
R6) An ASCONF-ACK SHOULD not be larger than the path MTU. In some R6) An ASCONF-ACK SHOULD not be larger than the path MTU. In some
circumstances an ASCONF-ACK may exceed the path MTU and in such a circumstances an ASCONF-ACK may exceed the path MTU and in such a
case IP fragmentation should be used to transmit the chunk. case IP fragmentation should be used to transmit the chunk.
If the sender of an ASCONF Chunk receives an Operational Error If the sender of an ASCONF Chunk receives an Operational Error
indicating that the ASCONF chunk type is not understood, then the indicating that the ASCONF chunk type is not understood, then the
sender MUST NOT send subsequent ASCONF Chunks to the peer. The sender MUST NOT send subsequent ASCONF Chunks to the peer. The
endpoint should also inform the upper layer application that the peer endpoint should also inform the upper layer application that the peer
endpoint does not support any of the extensions detailed in this endpoint does not support any of the extensions detailed in this
document. document.
4.2 Upon reception of an ASCONF Chunk. 4.2 Upon reception of an ASCONF Chunk.
When an endpoint receives an ASCONF Chunk from the remote peer When an endpoint receives an ASCONF Chunk from the remote peer
special procedures MAY be needed to identify the association the special procedures MAY be needed to identify the association the
ASCONF Chunk is associated with. To properly find the association the ASCONF Chunk is associated with. To properly find the association
following procedures should be followed: the following procedures should be followed:
L1) Use the source address and port number of the sender to attempt L1) Use the source address and port number of the sender to attempt
to identify the association (i.e. use the same method defined in to identify the association (i.e. use the same method defined in
RFC2960 [5] used for all other SCTP chunks). If found proceed to RFC2960 [6] used for all other SCTP chunks). If found proceed to
rule L4. rule L4.
L2) If the association is not found, use the address found in the L2) If the association is not found, use the address found in the
Address Parameter TLV combined with the port number found in the Address Parameter TLV combined with the port number found in the
SCTP common header. If found proceed to rule L4. SCTP common header. If found proceed to rule L4.
L3) If neither L1 or L2 locates the association, treat the chunk as L3) If neither L1 or L2 locates the association, treat the chunk as
an Out Of The Blue chunk as defined in RFC2960 [5]. an Out Of The Blue chunk as defined in RFC2960 [6].
L4) Follow the normal rules to validate the SCTP verification tag L4) Follow the normal rules to validate the SCTP verification tag
found in RFC2960 [5]. found in RFC2960 [6].
After identification and verification of the association, the After identification and verification of the association, the
following should be performed to properly process the ASCONF Chunk: following should be performed to properly process the ASCONF Chunk:
C1) Compare the value of the serial number to the value the endpoint C1) Compare the value of the serial number to the value the endpoint
stored in a new association variable 'Peer-Serial-Number'. This stored in a new association variable 'Peer-Serial-Number'. This
value MUST be initialized to the Initial TSN value minus 1. value MUST be initialized to the Initial TSN value minus 1.
C2) If the value found in the serial number is equal to the C2) If the value found in the serial number is equal to the
('Peer-Serial-Number' + 1), the endpoint MUST: ('Peer-Serial-Number' + 1), the endpoint MUST:
V1) Process the TLVs contained within the Chunk performing the V1) Process the TLVs contained within the Chunk performing the
appropriate actions as indicated by each TLV type. The TLVs appropriate actions as indicated by each TLV type. The TLVs
MUST be processed in order within the Chunk. For example, if MUST be processed in order within the Chunk. For example, if
the sender puts 3 TLVs in one chunk, the first TLV (the one the sender puts 3 TLVs in one chunk, the first TLV (the one
closest to the Chunk Header) in the Chunk MUST be processed closest to the Chunk Header) in the Chunk MUST be processed
first. The next TLV in the chunk (the middle one) MUST be first. The next TLV in the chunk (the middle one) MUST be
processed second and finally the last TLV in the Chunk MUST be processed second and finally the last TLV in the Chunk MUST be
skipping to change at page 20, line 25 skipping to change at page 21, line 8
MUST be processed in order within the Chunk. For example, if MUST be processed in order within the Chunk. For example, if
the sender puts 3 TLVs in one chunk, the first TLV (the one the sender puts 3 TLVs in one chunk, the first TLV (the one
closest to the Chunk Header) in the Chunk MUST be processed closest to the Chunk Header) in the Chunk MUST be processed
first. The next TLV in the chunk (the middle one) MUST be first. The next TLV in the chunk (the middle one) MUST be
processed second and finally the last TLV in the Chunk MUST be processed second and finally the last TLV in the Chunk MUST be
processed last. processed last.
V2) In processing the chunk, the receiver should build a response V2) In processing the chunk, the receiver should build a response
message with the appropriate error TLVs, as specified in the message with the appropriate error TLVs, as specified in the
Parameter type bits for any ASCONF Parameter it does not Parameter type bits for any ASCONF Parameter it does not
understand. To indicate an unrecognized parameter, cause type 8 understand. To indicate an unrecognized parameter, cause type
as defined in the ERROR in 3.3.10.8 of RFC2960 [5] should be 8 as defined in the ERROR in 3.3.10.8 of RFC2960 [6] should be
used. The endpoint may also use the response to carry used. The endpoint may also use the response to carry
rejections for other reasons such as resource shortages etc, rejections for other reasons such as resource shortages etc,
using the Error Cause TLV and an appropriate error condition. using the Error Cause TLV and an appropriate error condition.
Note: a positive response is implied if no error is indicated Note: a positive response is implied if no error is indicated
by the sender. by the sender.
V3) All responses MUST copy the ASCONF-Request Correlation ID V3) All responses MUST copy the ASCONF-Request Correlation ID
field received in the ASCONF parameter, from the TLV being field received in the ASCONF parameter, from the TLV being
responded to, into the ASCONF-Request Correlation ID field in responded to, into the ASCONF-Request Correlation ID field in
the response parameter. the response parameter.
V4) After processing the entire Chunk, the receiver of the ASCONF V4) After processing the entire Chunk, the receiver of the ASCONF
MUST send all TLVs for both unrecognized parameters and any MUST send all TLVs for both unrecognized parameters and any
other status TLVs inside the ASCONF-ACK chunk that acknowledges other status TLVs inside the ASCONF-ACK chunk that acknowledges
the arrival and processing of the ASCONF Chunk. the arrival and processing of the ASCONF Chunk.
V5) Update the 'Peer-Serial-Number' to the value found in the V5) Update the 'Peer-Serial-Number' to the value found in the
serial number field. serial number field.
C3) If the value found in the serial number is equal to the value C3) If the value found in the serial number is equal to the value
stored in the 'Peer-Serial-Number', the endpoint should: stored in the 'Peer-Serial-Number', the endpoint should:
X1) Parse the ASCONF Chunk TLVs but the endpoint MUST NOT take any X1) Parse the ASCONF Chunk TLVs but the endpoint MUST NOT take any
action on the TLVs parsed (since it has already performed these action on the TLVs parsed (since it has already performed these
actions). actions).
X2) Build a response message with the appropriate response TLVs as X2) Build a response message with the appropriate response TLVs as
specified in the ASCONF Parameter type bits, for any parameter specified in the ASCONF Parameter type bits, for any parameter
it does not understand or could not process. it does not understand or could not process.
X3) After parsing the entire Chunk, it MUST send any response TLV X3) After parsing the entire Chunk, it MUST send any response TLV
errors and status with an ASCONF-ACK chunk acknowledging the errors and status with an ASCONF-ACK chunk acknowledging the
arrival and processing of the ASCONF Chunk. arrival and processing of the ASCONF Chunk.
X4) The endpoint MUST NOT update its 'Peer-Serial-Number'. X4) The endpoint MUST NOT update its 'Peer-Serial-Number'.
Note: the response to the retransmitted ASCONF MUST be the same as Note: the response to the retransmitted ASCONF MUST be the same as
the original response. This MAY mean an implementation must keep the original response. This MAY mean an implementation must keep
state in order to respond with the same exact answer (including state in order to respond with the same exact answer (including
resource considerations that may have made the implementation resource considerations that may have made the implementation
refuse a request). refuse a request).
IMPLEMENTATION NOTE: As an optimization a receiver may wish to IMPLEMENTATION NOTE: As an optimization a receiver may wish to
save the last ASCONF-ACK for some predetermined period of time and save the last ASCONF-ACK for some predetermined period of time and
instead of re-processing the ASCONF (with the same serial number) instead of re-processing the ASCONF (with the same serial number)
it may just re-transmit the ASCONF-ACK. It may wish to use the it may just re-transmit the ASCONF-ACK. It may wish to use the
arrival of a new serial number to discard the previously saved arrival of a new serial number to discard the previously saved
ASCONF-ACK or any other means it may choose to expire the saved ASCONF-ACK or any other means it may choose to expire the saved
ASCONF-ACK. ASCONF-ACK.
C4) Otherwise, the ASCONF Chunk is discarded since it must be either C4) Otherwise, the ASCONF Chunk is discarded since it must be either
a stale packet or from an attacker. A receiver of such a packet a stale packet or from an attacker. A receiver of such a packet
skipping to change at page 23, line 4 skipping to change at page 23, line 12
arriving destined to the IP address being deleted MUST be ignored arriving destined to the IP address being deleted MUST be ignored
(see Section 4.3.1 for further details). (see Section 4.3.1 for further details).
D5) An endpoint MUST NOT delete its last remaining IP address from an D5) An endpoint MUST NOT delete its last remaining IP address from an
association. In other words if an endpoint is NOT multi-homed it association. In other words if an endpoint is NOT multi-homed it
MUST NOT use the delete IP address without an add IP address MUST NOT use the delete IP address without an add IP address
preceding the delete parameter in the ASCONF chunk. Or if an preceding the delete parameter in the ASCONF chunk. Or if an
endpoint sends multiple requests to delete IP addresses it MUST endpoint sends multiple requests to delete IP addresses it MUST
NOT delete all of the IP addresses that the peer has listed for NOT delete all of the IP addresses that the peer has listed for
the requester. the requester.
D6) An endpoint MUST NOT set an IP header source address for an SCTP D6) An endpoint MUST NOT set an IP header source address for an SCTP
packet holding the ASCONF Chunk to be the same as an address being packet holding the ASCONF Chunk to be the same as an address being
deleted by the ASCONF Chunk. deleted by the ASCONF Chunk.
D7) If a request is received to delete the last remaining IP address D7) If a request is received to delete the last remaining IP address
of a peer endpoint, the receiver MUST send an Error Cause TLV with of a peer endpoint, the receiver MUST send an Error Cause TLV with
the error cause set to the new error code 'Request to Delete Last the error cause set to the new error code 'Request to Delete Last
Remaining IP Address'. The requested delete MUST NOT be performed Remaining IP Address'. The requested delete MUST NOT be performed
or acted upon, other than to send the ASCONF-ACK. or acted upon, other than to send the ASCONF-ACK.
D8) If a request is received to delete an IP address which is also D8) If a request is received to delete an IP address which is also
the source address of the IP packet which contained the ASCONF the source address of the IP packet which contained the ASCONF
chunk, the receiver MUST reject this request. To reject the chunk, the receiver MUST reject this request. To reject the
request the receiver MUST send an Error Cause TLV set to the new request the receiver MUST send an Error Cause TLV set to the new
error code 'Request to Delete Source IP Address' (unless Rule D5 error code 'Request to Delete Source IP Address' (unless Rule D5
has also been violated, in which case the error code 'Request to has also been violated, in which case the error code 'Request to
Delete Last Remaining IP Address' is sent). Delete Last Remaining IP Address' is sent).
D9) If an endpoint receives an ADD IP address request and does not D9) If an endpoint receives an ADD IP address request and does not
have the local resources to add this new address to the have the local resources to add this new address to the
association, it MUST return an Error Cause TLV set to the new association, it MUST return an Error Cause TLV set to the new
error code 'Operation Refused Due to Resource Shortage'. error code 'Operation Refused Due to Resource Shortage'.
D10) If an endpoint receives an 'Out of Resource' error in response D10) If an endpoint receives an 'Out of Resource' error in response
to its request to ADD an IP address to an association, it must to its request to ADD an IP address to an association, it must
either ABORT the association or not consider the address part of either ABORT the association or not consider the address part of
the association. In other words if the endpoint does not ABORT the the association. In other words if the endpoint does not ABORT
association, it must consider the add attempt failed and NOT use the association, it must consider the add attempt failed and NOT
this address since its peer will treat SCTP packets destined to use this address since its peer will treat SCTP packets destined
the address as Out Of The Blue packets. to the address as Out Of The Blue packets.
D11) When an endpoint receiving an ASCONF to add an IP address sends D11) When an endpoint receiving an ASCONF to add an IP address sends
an 'Out of Resource' in its response, it MUST also fail any an 'Out of Resource' in its response, it MUST also fail any
subsequent add or delete requests bundled in the ASCONF. The subsequent add or delete requests bundled in the ASCONF. The
receiver MUST NOT reject an ADD and then accept a subsequent receiver MUST NOT reject an ADD and then accept a subsequent
DELETE of an IP address in the same ASCONF Chunk. In other words, DELETE of an IP address in the same ASCONF Chunk. In other words,
once a receiver begins failing any ADD or DELETE request, it must once a receiver begins failing any ADD or DELETE request, it must
fail all subsequent ADD or DELETE requests contained in that fail all subsequent ADD or DELETE requests contained in that
single ASCONF. single ASCONF.
D12) When an endpoint receives a request to delete an IP address that D12) When an endpoint receives a request to delete an IP address that
is the current primary address, it is an implementation decision is the current primary address, it is an implementation decision
as to how that endpoint chooses the new primary address. as to how that endpoint chooses the new primary address.
D13) When an endpoint receives a valid request to DELETE an IP D13) When an endpoint receives a valid request to DELETE an IP
address the endpoint MUST consider the address no longer as part address the endpoint MUST consider the address no longer as part
of the association. It MUST NOT send SCTP packets for the of the association. It MUST NOT send SCTP packets for the
association to that address and it MUST treat subsequent packets association to that address and it MUST treat subsequent packets
received from that address as Out Of The Blue. received from that address as Out Of The Blue.
During the time interval between sending out the ASCONF and During the time interval between sending out the ASCONF and
receiving the ASCONF-ACK it MAY be possible to receive DATA chunks receiving the ASCONF-ACK it MAY be possible to receive DATA chunks
out of order. The following examples illustrate these problems: out of order. The following examples illustrate these problems:
Endpoint-A Endpoint-Z Endpoint-A Endpoint-Z
---------- ---------- ---------- ----------
ASCONF[Add-IP:X]------------------------------> ASCONF[Add-IP:X]------------------------------>
/--ASCONF-ACK /--ASCONF-ACK
/ /
/--------/---New DATA: /--------/---New DATA:
skipping to change at page 24, line 41 skipping to change at page 24, line 40
/------------New DATA: /------------New DATA:
/ Destination / Destination
/ IP:X / IP:X
ASCONF [DEL-IP:X]---------/----------------> ASCONF [DEL-IP:X]---------/---------------->
<-----------------/------------------ASCONF-ACK <-----------------/------------------ASCONF-ACK
/ /
/ /
<-------------/ <-------------/
In this example we see a DATA chunk destined to the IP:X (which is In this example we see a DATA chunk destined to the IP:X (which is
about to be deleted) arriving after the deletion is complete. For the about to be deleted) arriving after the deletion is complete. For
ADD case an endpoint SHOULD consider the newly adding IP address the ADD case an endpoint SHOULD consider the newly adding IP address
valid for the association to receive data from during the interval valid for the association to receive data from during the interval
when awaiting the ASCONF-ACK. The endpoint MUST NOT source data from when awaiting the ASCONF-ACK. The endpoint MUST NOT source data from
this new address until the ASCONF-ACK arrives but it may receive out this new address until the ASCONF-ACK arrives but it may receive out
of order data as illustrated and MUST NOT treat this data as an OOTB of order data as illustrated and MUST NOT treat this data as an OOTB
datagram (please see RFC2960 [5] section 8.4). It MAY drop the data datagram (please see RFC2960 [6] section 8.4). It MAY drop the data
silently or it MAY consider it part of the association but it MUST silently or it MAY consider it part of the association but it MUST
NOT respond with an ABORT. NOT respond with an ABORT.
For the DELETE case, an endpoint MAY respond to the late arriving For the DELETE case, an endpoint MAY respond to the late arriving
DATA packet as an OOTB datagram or it MAY hold the deleting IP DATA packet as an OOTB datagram or it MAY hold the deleting IP
address for a small period of time as still valid. If it treats the address for a small period of time as still valid. If it treats the
DATA packet as an OOTB the peer will silently discard the ABORT DATA packet as an OOTB the peer will silently discard the ABORT
(since by the time the ABORT is sent the peer will have removed the (since by the time the ABORT is sent the peer will have removed the
IP address from this association). If the endpoint elects to hold the IP address from this association). If the endpoint elects to hold
IP address valid for a period of time, it MUST NOT hold it valid the IP address valid for a period of time, it MUST NOT hold it valid
longer than 2 RTO intervals for the destination being removed. longer than 2 RTO intervals for the destination being removed.
4.3.1 A special case for OOTB ABORT chunks 4.3.1 A special case for OOTB ABORT chunks
Another case worth mentioning is illustrated below: Another case worth mentioning is illustrated below:
Endpoint-A Endpoint-Z Endpoint-A Endpoint-Z
---------- ---------- ---------- ----------
New DATA:------------\ New DATA:------------\
skipping to change at page 25, line 43 skipping to change at page 25, line 42
For this case, during the deletion of an IP address, an Abort MUST be For this case, during the deletion of an IP address, an Abort MUST be
ignored if the destination address of the Abort message is that of a ignored if the destination address of the Abort message is that of a
destination being deleted. destination being deleted.
4.3.2 A special case for changing an address. 4.3.2 A special case for changing an address.
In some instances the sender may only have one IP address in an In some instances the sender may only have one IP address in an
association that is being renumbered. When this occurs, the sender association that is being renumbered. When this occurs, the sender
may not be able to send to the peer the appropriate ADD/DELETE pair may not be able to send to the peer the appropriate ADD/DELETE pair
and use the old address as a source in the IP header. For this reason and use the old address as a source in the IP header. For this
the sender MUST fill in the Address Parameter field with an address reason the sender MUST fill in the Address Parameter field with an
that is part of the association (in this case the one being deleted). address that is part of the association (in this case the one being
This will allow the receiver to locate the association without using deleted). This will allow the receiver to locate the association
the source address found in the IP header. without using the source address found in the IP header.
The receiver of such a chunk MUST always first use the source address The receiver of such a chunk MUST always first use the source address
found in the IP header in looking up the association. The receiver found in the IP header in looking up the association. The receiver
should attempt to use the address found in the Address Bytes field should attempt to use the address found in the Address Bytes field
only if the lookup fails using the source address from the IP header. only if the lookup fails using the source address from the IP header.
The receiver MUST reply to the source address of the packet in this The receiver MUST reply to the source address of the packet in this
case which is the new address that was added by the ASCONF (since the case which is the new address that was added by the ASCONF (since the
old address is no longer a part of the association after processing). old address is no longer a part of the association after processing).
4.4 Setting of the primary address 4.4 Setting of the primary address
skipping to change at page 27, line 9 skipping to change at page 27, line 9
receiver SHOULD perform. It is considered advice to the receiver of receiver SHOULD perform. It is considered advice to the receiver of
the best destination address to use in sending SCTP packets (in the the best destination address to use in sending SCTP packets (in the
requesters view). If a request arrives that asks the receiver to set requesters view). If a request arrives that asks the receiver to set
an address as primary that does not exist, the receiver should NOT an address as primary that does not exist, the receiver should NOT
honor the request, leaving its existing primary address unchanged. honor the request, leaving its existing primary address unchanged.
5. Security Considerations 5. Security Considerations
The ADD/DELETE of an IP address to an existing association does The ADD/DELETE of an IP address to an existing association does
provide an additional mechanism by which existing associations can be provide an additional mechanism by which existing associations can be
hijacked. Where the attacker is able to intercept and or alter the hijacked. Where the attacker is able to intercept and/or alter the
packets sent and received in an association, the use of this feature packets sent and received in an association, the use of this feature
MAY increase the ease with which an association may be overtaken. MAY increase the ease with which an association may be overtaken.
This threat SHOULD be considered when deploying a version of SCTP This threat SHOULD be considered when deploying a version of SCTP
that makes use of this feature. The IP Authentication Header RFC2402 that makes use of this feature. The IP Authentication Header RFC2402
[3] SHOULD be used when the threat environment requires stronger [3] SHOULD be used when the threat environment requires stronger
integrity protections, but does not require confidentiality. It integrity protections, but does not require confidentiality. It
should be noted that in the base SCTP specification RFC2960 [5], if should be noted that in the base SCTP specification RFC2960 [6], if
an attacker is able to intercept and or alter packets, even without an attacker is able to intercept and or alter packets, even without
this feature it is possible to hijack an existing association; please this feature it is possible to hijack an existing association; please
refer to Section 11 of RFC2960 [5]. refer to Section 11 of RFC2960 [6].
Future versions of this document may require use of purpose built
keys (pbk). A purpose built key mechanism assure that the endpoint
adding or deleting IP addresses is most likely the same endpoint that
the association started with aka the sender of the INIT or INIT-ACK.
6. IANA considerations 6. IANA considerations
This document defines the following new SCTP parameters, chunks and This document defines the following new SCTP parameters, chunks and
errors: errors:
o Two new chunk types, o Two new chunk types,
o Six parameter types, and o Six parameter types, and
o Three new SCTP error causes. o Three new SCTP error causes.
This document also defines a Adaption code point. The adaption code This document also defines a Adaption code point. The adaption code
point is a 32 bit interger that is assigned by IANA through an IETF point is a 32 bit interger that is assigned by IANA through an IETF
Consensus action as defined in RFC2434 [4]. Consensus action as defined in RFC2434 [4].
7. Acknowledgments 7. Acknowledgments
The authors wish to thank Jon Berger, Greg Kendall, Peter Lei, John The authors wish to thank Jon Berger, Greg Kendall, Seok Koh, Peter
Loughney, Ivan Arias Rodriguez, Renee Revis, Marshall Rose, and Chip Lei, John Loughney, Ivan Arias Rodriguez, Renee Revis, Marshall Rose,
Sharp for their invaluable comments. and Chip Sharp for their invaluable comments.
References The authors would also like to give special mention to Maria-Carmen
Belinchon and Ian Rytina for there early contributions to this
document and their thoughtful comments.
8 References
[1] Bradner, S., "The Internet Standards Process -- Revision 3", BCP [1] Bradner, S., "The Internet Standards Process -- Revision 3", BCP
9, RFC 2026, October 1996. 9, RFC 2026, October 1996.
[2] Bradner, S., "Key words for use in RFCs to Indicate Requirement [2] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[3] Kent, S. and R. Atkinson, "IP Authentication Header", RFC 2402, [3] Kent, S. and R. Atkinson, "IP Authentication Header", RFC 2402,
November 1998. November 1998.
[4] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA [4] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA
Considerations Section in RFCs", BCP 26, RFC 2434, October 1998. Considerations Section in RFCs", BCP 26, RFC 2434, October 1998.
[5] Stewart, R., Xie, Q., Morneault, K., Sharp, C., Schwarzbauer, [5] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629, June
1999.
[6] Stewart, R., Xie, Q., Morneault, K., Sharp, C., Schwarzbauer,
H., Taylor, T., Rytina, I., Kalla, M., Zhang, L. and V. Paxson, H., Taylor, T., Rytina, I., Kalla, M., Zhang, L. and V. Paxson,
"Stream Control Transmission Protocol", RFC 2960, October 2000. "Stream Control Transmission Protocol", RFC 2960, October 2000.
Authors' Addresses Authors' Addresses
Randall R. Stewart Randall R. Stewart
Cisco Systems, Inc. Cisco Systems, Inc.
8725 West Higgins Road 8725 West Higgins Road
Suite 300 Suite 300
Chicago, IL 60631 Chicago, IL 60631
skipping to change at page 31, line 21 skipping to change at page 30, line 30
EMail: qxie1@email.mot.com EMail: qxie1@email.mot.com
Michael Tuexen Michael Tuexen
Univ. of Applied Sciences Muenster Univ. of Applied Sciences Muenster
Stegerwaldstr. 39 Stegerwaldstr. 39
48565 Steinfurt 48565 Steinfurt
Germany Germany
EMail: tuexen@fh-muenster.de EMail: tuexen@fh-muenster.de
Ian Rytina
Ericsson
37/360 Elizabeth Street
Melbourne Victoria
Australia
Phone: +61-3-9301-6164
EMail: ian.rytina@ericsson.com
Maria-Carmen Belinchon
Ericsson
Spain
Phone:
EMail: emecbv@madrid.es.eu.ericsson.se
Phillip T. Conrad Phillip T. Conrad
Temple University University of Delaware
CIS Department Department of Computer and Information Sciences
Room 303, Computer Building (038-24) Newark, DE 19716
1805 N. Broad St.
Philadelphia, PA 19122
US US
Phone: +1 215 204 7910 Phone: +1 302 831 8622
EMail: conrad@acm.org EMail: conrad@acm.org
URI: http://www.cis.temple.edu/~conrad URI: http://www.cis.udel.edu/~pconrad
Appendix A. Abstract Address Handling Appendix A. Abstract Address Handling
A.1 General remarks A.1 General remarks
The following text provides a working definition of the endpoint The following text provides a working definition of the endpoint
notion to discuss address reconfiguration. It is not intended to notion to discuss address reconfiguration. It is not intended to
restrict implementations in any way, its goal is to provide as set of restrict implementations in any way, its goal is to provide as set of
definitions only. Using these definitions should make a discussion definitions only. Using these definitions should make a discussion
about address issues easier. about address issues easier.
skipping to change at page 34, line 8 skipping to change at page 32, line 8
There is one fundamental rule which restricts all generalized There is one fundamental rule which restricts all generalized
endpoints: endpoints:
For two different generalized endpoints gE' and gE'' with the same For two different generalized endpoints gE' and gE'' with the same
port number Port(gE') = Port(gE'') the address sets Addr(gE')(t) and port number Port(gE') = Port(gE'') the address sets Addr(gE')(t) and
Addr(gE'')(t) must be disjoint at every point of time. Addr(gE'')(t) must be disjoint at every point of time.
A.3 Associations A.3 Associations
Associations consists of two generalized endpoints and the two Associations consists of two generalized endpoints and the two
address sets known by the peer at any time. The precise definition is address sets known by the peer at any time. The precise definition
as follows: is as follows:
An association A between to different generalized endpoints gE' and An association A between to different generalized endpoints gE' and
gE'' is given by gE'' is given by
A = (gE', S', gE'', S'') A = (gE', S', gE'', S'')
where S'(t) and S''(t) are set of addresses at any time t such that where S'(t) and S''(t) are set of addresses at any time t such that
S'(t) is a non-empty subset of Addr(gE')(t) and S''(t) is a non-empty S'(t) is a non-empty subset of Addr(gE')(t) and S''(t) is a non-empty
subset of Addr(gE'')(t). subset of Addr(gE'')(t).
skipping to change at page 34, line 34 skipping to change at page 32, line 34
If the dependency on time is important the notion Addr(A, gE')(t) = If the dependency on time is important the notion Addr(A, gE')(t) =
S'(t) will be used. S'(t) will be used.
If A is an association between gE' and gE'' then Addr(A, gE') is the If A is an association between gE' and gE'' then Addr(A, gE') is the
subset of IP addresses of gE' which is known by gE'' and used by gE'. subset of IP addresses of gE' which is known by gE'' and used by gE'.
Association establishment between gE' and gE'' can be seen as: Association establishment between gE' and gE'' can be seen as:
1. gE' and gE'' do exist before the association. 1. gE' and gE'' do exist before the association.
2. If an INIT has to be send from gE' to gE'' address scoping rules 2. If an INIT has to be send from gE' to gE'' address scoping rules
and other limitations are applied to calculate the subset S' from and other limitations are applied to calculate the subset S' from
Addr(gE'). The addresses of S' are included in the INIT chunk. Addr(gE'). The addresses of S' are included in the INIT chunk.
3. If an INIT-ACK has to be send from gE'' to gE' address scoping 3. If an INIT-ACK has to be send from gE'' to gE' address scoping
rules and other limitations are applied to calculate the subset rules and other limitations are applied to calculate the subset
S'' from Addr(gE''). The addresses of S'' are included in the S'' from Addr(gE''). The addresses of S'' are included in the
INIT-ACK chunk. INIT-ACK chunk.
4. After the handshake the association A = (gE', S', gE'', S'') has 4. After the handshake the association A = (gE', S', gE'', S'') has
been established. been established.
5. Right after the association establishment Addr(A, gE') and 5. Right after the association establishment Addr(A, gE') and
Addr(A, gE'') are the addresses which have been seen on the wire Addr(A, gE'') are the addresses which have been seen on the wire
during the handshake. during the handshake.
A.4 Relationship with RFC 2960 A.4 Relationship with RFC 2960
RFC2960 [5] defines the notion of an endpoint. This subsection will RFC2960 [6] defines the notion of an endpoint. This subsection will
show that these endpoints are also (special) generalized endpoints. show that these endpoints are also (special) generalized endpoints.
RFC2960 [5] has no notion of address scoping or other address RFC2960 [6] has no notion of address scoping or other address
handling limitations and provides no mechanism to change the handling limitations and provides no mechanism to change the
addresses of an endpoint. addresses of an endpoint.
This means that an endpoint is simply a generalized endpoint which This means that an endpoint is simply a generalized endpoint which
does not depend on the time. Neither the Port nor the address list does not depend on the time. Neither the Port nor the address list
changes. changes.
During association setup no address scoping rules or other During association setup no address scoping rules or other
limitations will be applied. This means that for an association A limitations will be applied. This means that for an association A
between two endpoints gE' and gE'' the following is true: between two endpoints gE' and gE'' the following is true:
skipping to change at page 35, line 27 skipping to change at page 33, line 20
During association setup no address scoping rules or other During association setup no address scoping rules or other
limitations will be applied. This means that for an association A limitations will be applied. This means that for an association A
between two endpoints gE' and gE'' the following is true: between two endpoints gE' and gE'' the following is true:
Addr(A, gE') = Addr(gE') and Addr(A, gE'') = Addr(gE''). Addr(A, gE') = Addr(gE') and Addr(A, gE'') = Addr(gE'').
A.5 Rules for address manipulation A.5 Rules for address manipulation
The rules for address manipulation can now be stated in a simple way: The rules for address manipulation can now be stated in a simple way:
1. An address can be added to a generalized endpoint gE only if this 1. An address can be added to a generalized endpoint gE only if this
address is not an address of a different generalized endpoint address is not an address of a different generalized endpoint
with the same port number. with the same port number.
2. An address can be added to an association A with generalized 2. An address can be added to an association A with generalized
endpoint gE if it has been added to the generalized endpoint gE endpoint gE if it has been added to the generalized endpoint gE
first. This means that the address must be an element of Addr(gE) first. This means that the address must be an element of
first and then it can become an element of Addr(A, gE). But this Addr(gE) first and then it can become an element of Addr(A, gE).
is not necessary. If the association does not allow the But this is not necessary. If the association does not allow the
reconfiguration of the addresses only Addr(gE) can be modified. reconfiguration of the addresses only Addr(gE) can be modified.
3. An address can be deleted from an association A with generalized 3. An address can be deleted from an association A with generalized
endpoint gE as long as Addr(A, gE) stays non-empty. endpoint gE as long as Addr(A, gE) stays non-empty.
4. An address can be deleted from an generalized endpoint gE only if 4. An address can be deleted from an generalized endpoint gE only if
it has been removed from all associations having gE as a it has been removed from all associations having gE as a
generalized endpoint. generalized endpoint.
These rules simply make sure that the rules for the endpoints and These rules simply make sure that the rules for the endpoints and
associations given above are always fulfilled. associations given above are always fulfilled.
Intellectual Property Statement Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
skipping to change at page 36, line 8 skipping to change at page 34, line 8
4. An address can be deleted from an generalized endpoint gE only if 4. An address can be deleted from an generalized endpoint gE only if
it has been removed from all associations having gE as a it has been removed from all associations having gE as a
generalized endpoint. generalized endpoint.
These rules simply make sure that the rules for the endpoints and These rules simply make sure that the rules for the endpoints and
associations given above are always fulfilled. associations given above are always fulfilled.
Intellectual Property Statement Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it might or might not be available; nor does it represent that it has
has made any effort to identify any such rights. Information on the made any independent effort to identify any such rights. Information
IETF's procedures with respect to rights in standards-track and on the procedures with respect to rights in RFC documents can be
standards-related documentation can be found in BCP-11. Copies of found in BCP 78 and BCP 79.
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to Copies of IPR disclosures made to the IETF Secretariat and any
obtain a general license or permission for the use of such assurances of licenses to be made available, or the result of an
proprietary rights by implementors or users of this specification can attempt made to obtain a general license or permission for the use of
be obtained from the IETF Secretariat. such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF Executive this standard. Please address the information to the IETF at
Director. ietf-ipr@ietf.org.
Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved. Disclaimer of Validity
This document and translations of it may be copied and furnished to This document and the information contained herein are provided on an
others, and derivative works that comment on or otherwise explain it "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
or assist in its implementation may be prepared, copied, published OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
and distributed, in whole or in part, without restriction of any ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
kind, provided that the above copyright notice and this paragraph are INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
included on all such copies and derivative works. However, this INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
document itself may not be modified in any way, such as by removing WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be Copyright Statement
revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an Copyright (C) The Internet Society (2004). This document is subject
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING to the rights, licenses and restrictions contained in BCP 78, and
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING except as set forth therein, the authors retain all their rights.
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement Acknowledgment
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is currently provided by the
Internet Society. Internet Society.
 End of changes. 

This html diff was produced by rfcdiff 1.23, available from http://www.levkowetz.com/ietf/tools/rfcdiff/