draft-ietf-tsvwg-addip-sctp-06.txt   draft-ietf-tsvwg-addip-sctp-07.txt 
Network Working Group R. Stewart Network Working Group R. Stewart
Internet-Draft M. Ramalho Internet-Draft M. Ramalho
Expires: March 2, 2003 Cisco Systems, Inc. Expires: August 27, 2003 Cisco Systems, Inc.
Q. Xie Q. Xie
Motorola, Inc. Motorola, Inc.
M. Tuexen M. Tuexen
Siemens AG
I. Rytina I. Rytina
M. Belinchon M. Belinchon
Ericsson Ericsson
P. Conrad P. Conrad
Temple University Temple University
September 2002 February 26, 2003
Stream Control Transmission Protocol (SCTP) Dynamic Address Stream Control Transmission Protocol (SCTP) Dynamic Address
Reconfiguration Reconfiguration
draft-ietf-tsvwg-addip-sctp-06.txt draft-ietf-tsvwg-addip-sctp-07.txt
Status of this Memo Status of this Memo
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026. all provisions of Section 10 of RFC2026.
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 Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet- other groups may also distribute working documents as
Drafts. 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 http://
www.ietf.org/ietf/1id-abstracts.txt. 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 2, 2003. This Internet-Draft will expire on August 27, 2003.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved. Copyright (C) The Internet Society (2003). 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 (ASCONF-ACK) . . 6
3.2 New Parameter Types . . . . . . . . . . . . . . . . . . . . 7 3.2 New Parameter Types . . . . . . . . . . . . . . . . . . . . 7
3.2.1 Add IP Address . . . . . . . . . . . . . . . . . . . . . . . 8 3.2.1 Add IP Address . . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Error Cause Indication . . . . . . . . . . . . . . . . . . . 10 3.2.2 Delete IP Address . . . . . . . . . . . . . . . . . . . . . 9
3.4 Set Primary IP Address . . . . . . . . . . . . . . . . . . . 11 3.2.3 Error Cause Indication . . . . . . . . . . . . . . . . . . . 10
3.5 Success Indication . . . . . . . . . . . . . . . . . . . . . 12 3.2.4 Set Primary IP Address . . . . . . . . . . . . . . . . . . . 11
3.5.1 Adaptation Layer Indication . . . . . . . . . . . . . . . . 12 3.2.5 Success Indication . . . . . . . . . . . . . . . . . . . . . 12
3.6 New Error Causes . . . . . . . . . . . . . . . . . . . . . . 13 3.2.6 Adaptation Layer Indication . . . . . . . . . . . . . . . . 12
3.6.1 Error Cause: Request to Delete Last Remaining IP Address . . 13 3.3 New Error Causes . . . . . . . . . . . . . . . . . . . . . . 13
3.6.2 Error Cause: Operation Refused Due to Resource Shortage . . 14 3.3.1 Error Cause: Request to Delete Last Remaining IP Address . . 13
3.6.3 Error Cause: Request to Delete Source IP Address . . . . . . 15 3.3.2 Error Cause: Operation Refused Due to Resource Shortage . . 14
3.6.4 Error Cause: Association Aborted due to illegal ASCONF-ACK . 16 3.3.3 Error Cause: Request to Delete Source IP Address . . . . . . 15
3.3.4 Error Cause: Association Aborted due to illegal
ASCONF-ACK . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.3.5 Error Cause: Request refused - no authorization. . . . . . . 16
4. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 17 4. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1 ASCONF Chunk Procedures . . . . . . . . . . . . . . . . . . 17 4.1 ASCONF Chunk Procedures . . . . . . . . . . . . . . . . . . 17
4.1.1 Congestion Control of ASCONF Chunks . . . . . . . . . . . . 18 4.1.1 Congestion Control of ASCONF Chunks . . . . . . . . . . . . 18
4.2 Upon reception of an ASCONF Chunk. . . . . . . . . . . . . . 19 4.2 Upon reception of an ASCONF Chunk. . . . . . . . . . . . . . 19
4.3 General rules for address manipulation . . . . . . . . . . . 21 4.3 General rules for address manipulation . . . . . . . . . . . 21
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 References . . . . . . . . . . . . . . . . . . . . . . . . . 30
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 30 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 30
A. Abstract Address Handling . . . . . . . . . . . . . . . . . 33 A. Abstract Address Handling . . . . . . . . . . . . . . . . . 32
A.1 General remarks . . . . . . . . . . . . . . . . . . . . . . 33 A.1 General remarks . . . . . . . . . . . . . . . . . . . . . . 32
A.2 Generalized endpoints . . . . . . . . . . . . . . . . . . . 33 A.2 Generalized endpoints . . . . . . . . . . . . . . . . . . . 32
A.3 Associations . . . . . . . . . . . . . . . . . . . . . . . . 34 A.3 Associations . . . . . . . . . . . . . . . . . . . . . . . . 33
A.4 Relationship with RFC 2960 . . . . . . . . . . . . . . . . . 35 A.4 Relationship with RFC 2960 . . . . . . . . . . . . . . . . . 34
A.5 Rules for address manipulation . . . . . . . . . . . . . . . 35 A.5 Rules for address manipulation . . . . . . . . . . . . . . . 34
Full Copyright Statement . . . . . . . . . . . . . . . . . . 36 Intellectual Property and Copyright Statements . . . . . . . 35
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.
skipping to change at page 5, line 47 skipping to change at page 5, line 47
in the ASCONF Chunk are set to one. As defined in RFC2960 [5] in the ASCONF Chunk are set to one. As defined in RFC2960 [5]
section 3.2, setting these upper bits in this manner will cause the section 3.2, setting these upper bits in this manner will cause the
receiver that does not understand this chunk to skip the chunk and receiver that does not understand this chunk to skip the chunk and
continue 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 Type- information carried in the ASCONF Chunk uses the form of a
Length-Value (TLV), as described in "3.2.1 Optional/Variable-length Type-Length-Value (TLV), as described in "3.2.1 Optional/
Parameter Format" in RFC2960 [5], forall variable parameters. Variable-length Parameter Format" in RFC2960 [5], forall variable
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 9, line 20 skipping to change at page 9, line 20
| Type=5 | Length = 8 | | Type=5 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0a010101 | | Value=0x0a010101 |
+----------------+---------------+ +----------------+---------------+
Valid Chunk Appearance Valid Chunk Appearance
The Add IP Address parameter may only appear in the ASCONF Chunk The Add IP Address parameter may only appear in the ASCONF Chunk
type. type.
3.2.2 Delete 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 =0xC002 | Length = Variable | | Type =0xC002 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Request Correlation ID | | ASCONF-Request Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Parameter | | Address Parameter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 10, line 20 skipping to change at page 10, line 20
| Type=5 | Length = 8 | | Type=5 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0a010101 | | Value=0x0a010101 |
+----------------+---------------+ +----------------+---------------+
Valid Chunk Appearance Valid Chunk Appearance
The Delete IP Address parameter may only appear in the ASCONF Chunk The Delete IP Address parameter may only appear in the ASCONF Chunk
type. type.
3.3 Error Cause Indication 3.2.3 Error Cause 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 = 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 10, line 50 skipping to change at page 10, line 50
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 [5]). 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]. [5].
Valid Chunk Appearance Valid Chunk Appearance
The Error Cause Indication parameter may only appear in the ASCONF- The Error Cause Indication parameter may only appear in the
ACK chunk type. ASCONF-ACK chunk type.
3.4 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ASCONF-Request Correlation ID | | ASCONF-Request Correlation ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Address Parameter | | Address Parameter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 11, line 40 skipping to change at page 11, line 40
3.3.2.1 of RFC2960 [5]. The complete TLV is wrapped within this 3.3.2.1 of RFC2960 [5]. 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 [5]). 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 = 18 | | 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 the INIT, or the INIT-ACK chunk type. The inclusion of this
parameter in the INIT or INIT-ACK can be used to indicate an initial parameter in the INIT or INIT-ACK can be used to indicate an initial
preference of primary address. preference of primary address.
3.5 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
By default if a responding endpoint does not report an error for any By default if a responding endpoint does not report an error for any
skipping to change at page 12, line 40 skipping to change at page 12, line 40
request parameter. The receiver of the ASCONF Chunk will copy this request parameter. The receiver of the ASCONF Chunk will copy this
32 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.
3.5.1 Adaptation Layer Indication 3.2.6 Adaptation Layer 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 =0xC006 | Length = Variable | | Type =0xC006 | Length = Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Adaption Code point | | Adaption Code point |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
This parameter is specified for the communication of peer upper layer This parameter is specified for the communication of peer upper layer
protocols. It is envisioned to be used for flow control and other protocols. It is envisioned to be used for flow control and other
adaptation layers that require an indication to be carried in the adaptation layers that require an indication to be carried in the
INIT and INIT-ACK. Each adaptation layer that is defined that wishes INIT and INIT-ACK. Each adaptation layer that is defined that wishes
to use this parameter MUST specify a an adaption code point in an to use this parameter MUST specify a an adaption code point in an
appropriate RFC defining its use and meaning. This parameter SHOULD appropriate RFC defining its use and meaning. This parameter SHOULD
NOT be examined by the receiving SCTP implementation and should be NOT be examined by the receiving SCTP implementation and should be
passed opaquely to the upper layer protocol. passed opaquely to the upper layer protocol.
Valid Chunk Appearance Valid Chunk Appearance
The Adaptation Layer Indication parameter may appear in INIT or INIT- The Adaptation Layer Indication parameter may appear in INIT or
ACK chunk and SHOULD be passed to the receivers upper layer protocol. INIT-ACK chunk and SHOULD be passed to the receivers upper layer
protocol.
3.6 New Error Causes 3.3 New Error Causes
Four new Error Causes are added to the SCTP Operational Errors, Four new Error Causes are added to the SCTP Operational Errors,
primarily for use in the ASCONF-ACK chunk. primarily for use in the ASCONF-ACK chunk.
Cause Code Cause Code
Value Cause Code Value Cause Code
--------- ---------------- --------- ----------------
0x0100 Request to Delete Last Remaining IP Address. 0x0100 Request to Delete Last Remaining IP Address.
0x0101 Operation Refused Due to Resource Shortage. 0x0101 Operation Refused Due to Resource Shortage.
0x0102 Request to Delete Source IP Address. 0x0102 Request to Delete Source IP Address.
0x0103 Association Aborted due to illegal ASCONF-ACK 0x0103 Association Aborted due to illegal ASCONF-ACK
0x0104 Request refused - no authorization.
Table 4: New Error Causes Table 4: New Error Causes
3.6.1 Error Cause: Request to Delete Last Remaining IP Address 3.3.1 Error Cause: Request to Delete Last Remaining IP Address
Cause of error Cause of error
Request to Delete Last Remaining IP address: The receiver of this Request to Delete Last Remaining IP address: The receiver of this
error sent a request to delete the last IP address from its error sent a request to delete the last IP address from its
association with its peer. This error indicates that the request is association with its peer. This error indicates that the request is
rejected. 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
skipping to change at page 13, line 48 skipping to change at page 14, line 4
rejected. 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=0x0100 | Cause Length=Variable | | Cause Code=0x0100 | Cause Length=Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\ TLV-Copied-From-ASCONF / \ TLV-Copied-From-ASCONF /
/ \ / \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
An example of a failed delete in an Error Cause TLV would look as An example of a failed delete in an Error Cause TLV would look as
follows in the response ASCONF-ACK message: follows in the response ASCONF-ACK message:
+--------------------------------+ +--------------------------------+
| Type = 0xC003 | Length = 24 | | Type = 0xC003 | Length = 24 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023476 | | Cause=0x0100 | Length = 20 |
+--------------------------------+
| Cause=0x0100 | Length = 16 |
+----------------+---------------+ +----------------+---------------+
| Type= 0xC002 | Length = 12 | | Type= 0xC002 | Length = 16 |
+----------------+---------------+ +----------------+---------------+
| C-ID = 0x01023476 |
+--------------------------------+
| Type=0x0005 | Length = 8 | | Type=0x0005 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0A010101 | | Value=0x0A010101 |
+----------------+---------------+ +----------------+---------------+
3.6.2 Error Cause: Operation Refused Due to Resource Shortage 3.3.2 Error Cause: Operation Refused Due to Resource Shortage
Cause of error Cause of error
This error cause is used to report a failure by the receiver to This error cause is used to report a failure by the receiver to
perform the requested operation due to a lack of resources. The perform the requested operation due to a lack of resources. The
entire TLV that is refused is copied from the ASCONF into the error entire TLV that is refused is copied from the ASCONF into the error
cause. cause.
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
skipping to change at page 15, line 8 skipping to change at page 15, line 8
\ TLV-Copied-From-ASCONF / \ TLV-Copied-From-ASCONF /
/ \ / \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
An example of a failed addition in an Error Cause TLV would look as An example of a failed addition in an Error Cause TLV would look as
follows in the response ASCONF-ACK message: follows in the response ASCONF-ACK message:
+--------------------------------+ +--------------------------------+
| Type = 0xC003 | Length = 24 | | Type = 0xC003 | Length = 24 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023474 | | Cause=0x0101 | Length = 20 |
+--------------------------------+
| Cause=0x0101 | Length = 16 |
+----------------+---------------+ +----------------+---------------+
| Type=0xC001 | Length = 12 | | Type=0xC001 | Length = 16 |
+--------------------------------+
| C-ID = 0x01023474 |
+--------------------------------+ +--------------------------------+
| Type=0x0005 | Length = 8 | | Type=0x0005 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0A010101 | | Value=0x0A010101 |
+----------------+---------------+ +----------------+---------------+
3.6.3 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. a request to delete the source IP address of the ASCONF message.
This 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 15, line 42 skipping to change at page 15, line 42
\ TLV-Copied-From-ASCONF / \ TLV-Copied-From-ASCONF /
/ \ / \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
An example of a failed delete in an Error Cause TLV would look as An example of a failed delete in an Error Cause TLV would look as
follows in the response ASCONF-ACK message: follows in the response ASCONF-ACK message:
+--------------------------------+ +--------------------------------+
| Type = 0xC003 | Length = 24 | | Type = 0xC003 | Length = 24 |
+--------------------------------+ +--------------------------------+
| C-ID = 0x01023476 | | Cause=0x0102 | Length = 20 |
+--------------------------------+
| Cause=0x0102 | Length = 16 |
+----------------+---------------+ +----------------+---------------+
| Type=0xC002 | Length = 12 | | Type=0xC002 | Length = 16 |
+----------------+---------------+ +----------------+---------------+
| C-ID = 0x01023476 |
+--------------------------------+
| Type=0x0005 | Length = 8 | | Type=0x0005 | Length = 8 |
+----------------+---------------+ +----------------+---------------+
| Value=0x0A010101 | | Value=0x0A010101 |
+----------------+---------------+ +----------------+---------------+
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.
3.6.4 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 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.
Cause of error
This error cause may be included to reject a request based on local
security policies.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cause Code=0x0104 | Cause Length=Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
\ TLV-Copied-From-ASCONF /
/ \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4. Procedures 4. Procedures
This section will lay out the specific procedures for address This section will lay out the specific procedures for address
configuration change chunk type and its processing. configuration change chunk type and its processing.
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:
skipping to change at page 18, line 52 skipping to change at page 18, line 52
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. that these transfers MUST NOT cause congestion within the network.
To achieve this, we place these restrictions on the transfer of To achieve this, we place these restrictions on the transfer of
ASCONF 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 in- restriction binds each side, so at any time two ASCONF may be
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.
skipping to change at page 20, line 10 skipping to change at page 20, line 10
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 [5].
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 ('Peer- C2) If the value found in the serial number is equal to the
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
processed last. processed last.
skipping to change at page 29, line 7 skipping to change at page 29, line 7
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, Peter Lei, John Loughney, Ivan The authors wish to thank Jon Berger, Greg Kendall, Peter Lei, John
Arias Rodriguez, Renee Revis, Marshall Rose, and Chip Sharp for their Loughney, Ivan Arias Rodriguez, Renee Revis, Marshall Rose, and Chip
invaluable comments. Sharp for their invaluable comments.
References 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,
skipping to change at page 31, line 14 skipping to change at page 31, line 14
Qiaobing Xie Qiaobing Xie
Motorola, Inc. Motorola, Inc.
1501 W. Shure Drive, #2309 1501 W. Shure Drive, #2309
Arlington Heights, IL 60004 Arlington Heights, IL 60004
USA USA
Phone: +1-847-632-3028 Phone: +1-847-632-3028
EMail: qxie1@email.mot.com EMail: qxie1@email.mot.com
Michael Tuexen Michael Tuexen
Siemens AG
ICN WN CS SE 5
D-81359 Munich
Germany Germany
Phone: +49 89 722 47210 Phone:
EMail: Michael.Tuexen@icn.siemens.de EMail: tuexen@fr-muenster.de
Ian Rytina Ian Rytina
Ericsson Ericsson
37/360 Elizabeth Street 37/360 Elizabeth Street
Melbourne Victoria Melbourne Victoria
Australia Australia
Phone: +61-3-9301-6164 Phone: +61-3-9301-6164
EMail: ian.rytina@ericsson.com EMail: ian.rytina@ericsson.com
skipping to change at page 36, line 5 skipping to change at page 35, line 5
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.
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Acknowledgement Acknowledgement
 End of changes. 

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