draft-ietf-mpls-ldp-mtu-extensions-03.txt   rfc3988.txt 
Network Working Group B. Black Network Working Group B. Black
Internet Draft Layer8 Networks Request for Comments: 3988 Layer8 Networks
Category: Experimental K. Kompella Category: Experimental K. Kompella
Juniper Networks Juniper Networks
Expires: October 2004 April 2004 January 2005
Maximum Transmission Unit Signalling Extensions Maximum Transmission Unit Signalling Extensions
for the Label Distribution Protocol for the Label Distribution Protocol
draft-ietf-mpls-ldp-mtu-extensions-03.txt
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
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The list of Internet-Draft Shadow Directories can be accessed at This memo defines an Experimental Protocol for the Internet
http://www.ietf.org/shadow.html. community. It does not specify an Internet standard of any kind.
Discussion and suggestions for improvement are requested.
Distribution of this memo is unlimited.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved. Copyright (C) The Internet Society (2005).
Abstract Abstract
Proper functioning of RFC 1191 path Maximum Transmission Unit (MTU) Proper functioning of RFC 1191 path Maximum Transmission Unit (MTU)
discovery requires that IP routers have knowledge of the MTU for each discovery requires that IP routers have knowledge of the MTU for each
link to which they are connected. As currently specified, the Label link to which they are connected. As currently specified, the Label
Distribution Protocol (LDP) does not have the ability to signal the Distribution Protocol (LDP) does not have the ability to signal the
MTU for a Label Switched Path (LSP) to the ingress Label Switching MTU for a Label Switched Path (LSP) to the ingress Label Switching
Router (LSR). In the absence of this functionality, the MTU for each Router (LSR). In the absence of this functionality, the MTU for each
LSP must be statically configured by network operators or by LSP must be statically configured by network operators or by
equivalent, off-line mechanisms. equivalent off-line mechanisms.
This document specifies experimental extensions to LDP in support of This document specifies experimental extensions to LDP in support of
LSP MTU discovery. LSP MTU discovery.
Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 [1].
Changes from last version
[Note to RFC Editor: please remove this section before publishing.]
- changed category to Experimental
- incorporated suggestions from WG chairs and IESG
1. Introduction 1. Introduction
As currently specified in [2], the LDP protocol for MPLS does not As currently specified in [2], the LDP protocol for MPLS does not
support signalling of the MTU for LSPs to ingress LSRs. This support signalling of the MTU for LSPs to ingress LSRs. This
functionality is essential to the proper functioning of RFC 1191 path functionality is essential to the proper functioning of RFC 1191 path
MTU detection [3]. Without knowledge of the MTU for an LSP, edge MTU detection [3]. Without knowledge of the MTU for an LSP, edge
LSRs may transmit packets along that LSP which are, according to [4], LSRs may transmit packets along that LSP which are, according to [4],
too big. Such packets may be silently discarded by LSRs along the too big. These packets may be silently discarded by LSRs along the
LSP, effectively preventing communication between certain end hosts. LSP, effectively preventing communication between certain end hosts.
The solution proposed in this document enables automatic The solution proposed in this document enables automatic
determination of the MTU for an LSP with the addition of a Type- determination of the MTU for an LSP by adding a Type-Length-Value
Length-Value triplet (TLV) to carry MTU information for a Forwarding triplet (TLV) to carry MTU information for a Forwarding Equivalence
Equivalence Class (FEC) between adjacent LSRs in LDP Label Mapping Class (FEC) between adjacent LSRs in LDP Label Mapping messages.
messages. This information is sufficient for a set of LSRs along the This information is sufficient for a set of LSRs along the path
path followed by an LSP to discover either the exact MTU for that followed by an LSP to discover either the exact MTU for that LSP, or
LSP, or an approximation which is no worse than could be generated an approximation that is no worse than could be generated with local
with local information on the ingress LSR. information on the ingress LSR.
1.1. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14, RFC 2119 [1].
2. MTU Signalling 2. MTU Signalling
The signalling procedure described in this document employs the The signalling procedure described in this document employs the
addition of a single TLV to LDP Label Mapping messages and a simple addition of a single TLV to LDP Label Mapping messages and a simple
algorithm for LSP MTU calculation. algorithm for LSP MTU calculation.
2.1. Definitions 2.1. Definitions
Link MTU: the MTU of a given link. This size includes the IP header Link MTU: The MTU of a given link. This size includes the IP header
and data (or other payload) and the label stack, but does not include and data (or other payload) and the label stack but does not include
any lower-layer headers. A link may be an interface (such as any lower-layer headers. A link may be an interface (such as
Ethernet or Packet-over-SONET), a tunnel (such as GRE or IPsec) or an Ethernet or Packet-over-SONET), a tunnel (such as GRE or IPsec), or
LSP. an LSP.
Peer LSRs: for LSR A and FEC F, this is the set of LSRs that sent a Peer LSRs: For LSR A and FEC F, this is the set of LSRs that sent a
Label Mapping for FEC F to A. Label Mapping for FEC F to A.
Downstream LSRs: for LSR A and FEC F, this is the subset of A's peer Downstream LSRs: For LSR A and FEC F, this is the subset of A's peer
LSRs for FEC F to whom A will forward packets for the FEC. LSRs for FEC F to which A will forward packets for the FEC.
Typically, this subset is determined via the routing table. Typically, this subset is determined via the routing table.
Hop MTU: the MTU of an LSP hop between an upstream LSR A and a Hop MTU: The MTU of an LSP hop between an upstream LSR, A, and a
downstream LSR B. This size includes the IP header and data (or downstream LSR, B. This size includes the IP header and data (or
other payload) and the part of the label stack that is considered other payload) and the part of the label stack that is considered
payload as far as this LSP goes. It does not include any lower-level payload as far as this LSP goes. It does not include any lower-level
headers. (Note: if there are multiple links between A and B, the Hop headers. (Note: If there are multiple links between A and B, the Hop
MTU is the minimum of the Hop MTU of those links used for MTU is the minimum of the Hop MTU of those links used for
forwarding.) forwarding.)
LSP MTU: the MTU of an LSP from a given LSR to the egress(es), over
LSP MTU: The MTU of an LSP from a given LSR to the egress(es), over
each valid (forwarding) path. This size includes the IP header and each valid (forwarding) path. This size includes the IP header and
data (or other payload) and any part of the label stack that was data (or other payload) and any part of the label stack that was
received by the ingress LSR before it placed the packet into the LSP received by the ingress LSR before it placed the packet into the LSP
(this part of the label stack is considered part of the payload for (this part of the label stack is considered part of the payload for
this LSP). The size does not include any lower-level headers. this LSP). The size does not include any lower-level headers.
2.2. Example 2.2. Example
Consider LSRs A-F interconnected as follows: Consider LSRs A - F, interconnected as follows:
M P M P
_____ C ===== _____ C =====
/ | \ / | \
A ~~~~~ B ===== D ----- E ----- F A ~~~~~ B ===== D ----- E ----- F
L N Q R L N Q R
Say that the link MTU for link L is 9216, for links M, Q and R is Say that the link MTU for link L is 9216; for links M, Q, and R,
4470, and for N and P is 1500. 4470; and for N and P, is 1500.
Consider a FEC X for which F is the egress, and say that all LSRs Consider an FEC X for which F is the egress, and say that all LSRs
advertise X to their neighbors. advertise X to their neighbors.
Note that while LDP may be running on the C-D link, it is not used Note that although LDP may be running on the C - D link, it is not
for forwarding (e.g., because it has a high metric). In particular, used for forwarding (e.g., because it has a high metric). In
D is an LDP neighbor of C, but D is not one of C's downstream LSRs particular, D is an LDP neighbor of C, but D is not one of C's
for FEC X. downstream LSRs for FEC X.
E's peers for FEC X are C, D and F. Say E chooses F as its E's peers for FEC X are C, D, and F. Say that E chooses F as its
downstream LSR for X. E's Hop MTU for link R is 4466. If F downstream LSR for X. E's Hop MTU for link R is 4466. If F
advertised an implicit null label to E, then E MAY set the Hop MTU advertised an implicit null label to E, then E MAY set the Hop MTU
for R to 4470. for R to 4470.
C's peers for FEC X are B, D and E. Say C chooses E as its C's peers for FEC X are B, D, and E. Say that C chooses E as its
downstream LSR for X. Similarly, A chooses B, B chooses C and D downstream LSR for X. Similarly, A chooses B, B chooses C and D
(equal cost multi-path), D chooses E and E chooses F (respectively) (equal cost multi-path), D chooses E, and E chooses F (respectively)
as their downstream LSRs. as downstream LSRs.
C's Hop MTU to E for FEC X is 1496. B's Hop MTU to C is 4466, and to C's Hop MTU to E for FEC X is 1496. B's Hop MTU to C is 4466 and to
D is 1496. A's LSP MTU for FEC X is 1496. If A has another LSP for D is 1496. A's LSP MTU for FEC X is 1496. If A has another LSP for
FEC Y to F (learned via targetted LDP) that rides over the LSP for FEC Y to F (learned via targeted LDP) that rides over the LSP for FEC
FEC X, the MTU for that LSP would be 1492. X, the MTU for that LSP would be 1492.
If B had a targetted LDP session to E, say over an RSVP-TE tunnel T, If B had a targeted LDP session to E (e.g., over an RSVP-TE tunnel T)
and B received a Mapping for FEC X over the targetted LDP session, and B received a Mapping for FEC X over the targeted LDP session,
then E would also be B's peer, and E may be chosen as a downstream then E would also be B's peer, and E may be chosen as a downstream
LSR for B. In that case, B's LSP MTU for FEC X would then be the LSR for B. In that case, B's LSP MTU for FEC X would then be the
smaller of {(T's MTU - 4), E's LSP MTU for X}. smaller of {(T's MTU - 4), E's LSP MTU for X}.
This memo describes how A determines its LSP MTU for FECs X and Y. This memo describes how A determines its LSP MTU for FECs X and Y.
2.3. Signalling Procedure 2.3. Signalling Procedure
The procedure for signalling the MTU is performed hop-by-hop by each The procedure for signalling the MTU is performed hop-by-hop by each
LSR L along an LSP for a given FEC F. The steps are as follows: LSR L along an LSP for a given FEC, F. The steps are as follows:
1. First, L computes the its LSP MTU for FEC F: 1. First, L computes its LSP MTU for FEC F:
A. If L is the egress for F, L sets the LSP MTU for F to 65535. A. If L is the egress for F, L sets the LSP MTU for F to 65535.
B. [OPTIONAL] If L's only downstream LSR is the egress for F B. [OPTIONAL] If L's only downstream LSR is the egress for F
(i.e., L is a penultimate hop for F), and L receives an (i.e., L is a penultimate hop for F) and L receives an implicit
implicit null label as its Mapping for F, then L can set the null label as its Mapping for F, then L can set the Hop MTU for
Hop MTU for its downstream link to the link MTU instead of its downstream link to the link MTU instead of (link MTU - 4
(link MTU - 4 octets). L's LSP MTU for F is the Hop MTU. octets). L's LSP MTU for F is the Hop MTU.
C. Otherwise (L is not the egress LSR), L computes the LSP MTU C. Otherwise (L is not the egress LSR), L computes the LSP MTU for
for F as follows: F as follows:
a) L determines its downstream LSRs for FEC F. a) L determines its downstream LSRs for FEC F.
b) For each downstream LSR Z, L computes the minimum of the b) For each downstream LSR Z, L computes the minimum of the Hop
Hop MTU to Z and the LSP MTU in the MTU TLV that Z MTU to Z and the LSP MTU in the MTU TLV that Z advertised to
advertised to L. If Z did not include the MTU TLV in its L. If Z did not include the MTU TLV in its Label Mapping,
Label Mapping, then Z's LSP MTU is set to 65535. then Z's LSP MTU is set to 65535.
c) L sets its LSP MTU to the minimum of the MTUs it computed c) L sets its LSP MTU to the minimum of the MTUs it computed
for its downstream LSRs. for its downstream LSRs.
2. For each LDP neighbor (direct or targetted) of L to which L 2. For each LDP neighbor (direct or targeted) of L to which L decides
decides to send a Mapping for FEC F, L attaches an MTU TLV with to send a Mapping for FEC F, L attaches an MTU TLV with the LSP
the LSP MTU that it computed for this FEC. L MAY (because of MTU that it computed for this FEC. L MAY (because of policy or
policy or other reasons) advertise a smaller MTU than it has for other reasons) advertise a smaller MTU than it has computed,
computed, but L MUST NOT advertise a larger MTU. but L MUST NOT advertise a larger MTU.
3. When a new MTU is received for FEC F from a downstream LSR, or 3. When a new MTU is received for FEC F from a downstream LSR or the
the set of downstream LSRs for F changes, L returns to Step 1. set of downstream LSRs for F changes, L returns to step 1. If the
If the newly computed LSP MTU is unchanged, L SHOULD NOT newly computed LSP MTU is unchanged, L SHOULD NOT advertise new
advertise new information to its neighbors. Otherwise, L information to its neighbors. Otherwise, L readvertises its
readvertises its Mappings for F to all its peers with an updated Mappings for F to all its peers with an updated MTU TLV.
MTU TLV.
This behavior is standard for attributes such as path vector and This behavior is standard for attributes such as path vector and
hop count, and the same rules apply, as specified in [2]. hop count, and the same rules apply, as specified in [2].
If the LSP MTU decreases, L SHOULD readvertise the new MTU If the LSP MTU decreases, L SHOULD readvertise the new MTU
immediately; if the LSP MTU increases, L MAY hold down the immediately; if the LSP MTU increases, L MAY hold down the
readvertisement. readvertisement.
2.4. MTU TLV 2.4. MTU TLV
The MTU TLV encodes information on the maximum transmission unit for The MTU TLV encodes information on the maximum transmission unit for
an LSP, from the advertising LSR to the egress(es) over all valid an LSP, from the advertising LSR to the egress(es) over all valid
paths. paths.
The encoding for the MTU TLV is: The encoding for the MTU TLV is as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1|1| MTU TLV (0x0XXX) | Length | |1|1| MTU TLV (0x0601) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | | MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
MTU MTU
This is a 16-bit unsigned integer that represents the MTU in octets This is a 16-bit unsigned integer that represents the MTU in octets
for an LSP or segment of an LSP. for an LSP or a segment of an LSP.
Note that the U and F bits are set. An LSR that doesn't recognize Note that the U and F bits are set. An LSR that doesn't recognize
the MTU TLV MUST ignore it when it processes the Label Mapping the MTU TLV MUST ignore it when it processes the Label Mapping
message, and forward the TLV to its peers. This may result in the message and forward the TLV to its peers. This may result in the
incorrect computation of the LSP MTU; however, silently forwarding incorrect computation of the LSP MTU; however, silently forwarding
the MTU TLV preserves maximal amount of information about the LSP the MTU TLV preserves the maximal amount of information about the LSP
MTU. MTU.
3. Example of Operation 3. Example of Operation
Consider the example network in section 2.2. Table 1 describes, for Consider the network example in Section 2.2. For each LSR, Table 1
each LSR, the links to its downstream LSRs, the Hop MTU for the peer, describes the links to its downstream LSRs, the Hop MTU for the peer,
the LSP MTU received from the peer, and the LSR's computed LSP MTU. the LSP MTU received from the peer, and the LSR's computed LSP MTU.
Now consider the same network with the following changes: there is an Now consider the same network with the following changes: There is an
LSP T from B to E, and a targetted LDP session from B to E. B's peer LSP T from B to E, and a targeted LDP session from B to E. B's peer
LSRs are A, C, D and E; B's downstream LSRs are D and E; to reach E, LSRs are A, C, D, and E; B's downstream LSRs are D and E; to reach E,
B chooses to go over T. The LSP MTU for LSP T is 1496. This B chooses to go over T. The LSP MTU for LSP T is 1496. This
information is depicted in Table 2. information is depicted in Table 2.
LSR | Link | Hop MTU | Recvd MTU | LSP MTU LSR | Link | Hop MTU | Recvd MTU | LSP MTU
-------------------------------------------------- --------------------------------------------------
F | - | 65535 | - | 65535 F | - | 65535 | - | 65535
-------------------------------------------------- --------------------------------------------------
E | R | 4466 | F: 65535 | 4466 E | R | 4466 | F: 65535 | 4466
-------------------------------------------------- --------------------------------------------------
D | Q | 4466 | E: 4466 | 4466 D | Q | 4466 | E: 4466 | 4466
skipping to change at page 7, line 47 skipping to change at page 6, line 47
Table 2 Table 2
4. Using the LSP MTU 4. Using the LSP MTU
An ingress LSR that forwards an IP packet into an LSP whose MTU it An ingress LSR that forwards an IP packet into an LSP whose MTU it
knows MUST either fragment the IP packet to the LSP's MTU (if the knows MUST either fragment the IP packet to the LSP's MTU (if the
Don't Fragment bit is clear) or drop the packet and respond with an Don't Fragment bit is clear) or drop the packet and respond with an
ICMP Destination Unreachable message to the source of the packet, ICMP Destination Unreachable message to the source of the packet,
with the Code indicating "fragmentation needed and DF set", and the with the Code indicating "fragmentation needed and DF set", and the
Next-Hop MTU set to the LSP MTU. In other words, the LSR behaves as Next-Hop MTU set to the LSP MTU. In other words, the LSR behaves as
RFC 1191 says, except it treats the LSP as the next hop "network". RFC 1191 says, except that it treats the LSP as the next hop
"network".
If the payload for the LSP is not an IP packet, the LSR MUST forward If the payload for the LSP is not an IP packet, the LSR MUST forward
the packet if it fits (size <= LSP MTU), and SHOULD drop it if it the packet if it fits (size <= LSP MTU) and SHOULD drop it if it
doesn't fit. doesn't.
5. Protocol Interaction 5. Protocol Interaction
5.1. Interaction With LSRs Which Do Not Support MTU Signalling 5.1. Interaction with LSRs that Do Not Support MTU Signalling
Changes in MTU for sections of an LSP may cause intermediate LSRs to Changes in MTU for sections of an LSP may cause intermediate LSRs to
generate unsolicited label Mapping messages to advertise the new MTU. generate unsolicited label Mapping messages to advertise the new MTU.
LSRs which do not support MTU signalling will accept these messages, LSRs that do not support MTU signalling will, due to message and TLV
but will ignore them (see Section 2.4). processing mechanisms specified in RFC3036 [2], accept the messages
carrying the MTU TLV but will ignore the TLV and forward the TLV to
the upstream nodes (see Section 2.4).
5.2. Interaction with CR-LDP and RSVP-TE 5.2. Interaction with CR-LDP and RSVP-TE
The MTU TLV can be used to discover the Path MTU of both LDP LSPs and The MTU TLV can be used to discover the Path MTU of both LDP LSPs and
CR-LDP LSPs. This proposal is not impacted in the presence of LSPs CR-LDP LSPs. This proposal is not impacted in the presence of LSPs
created using CR-LDP, as specified in [5]. created with CR-LDP, as specified in [5].
Note that LDP/CR-LDP LSPs may tunnel through other LSPs signalled Note that LDP/CR-LDP LSPs may tunnel through other LSPs signalled
using LDP, CR-LDP or RSVP-TE [6]; the mechanism suggested here using LDP, CR-LDP, or RSVP-TE [6]; the mechanism suggested here
applies in all these cases, essentially by treating the tunnel LSPs applies in all of these cases, essentially by treating the tunnel
as links. LSPs as links.
Normative References 6. References
6.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement [1] 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.
[2] Andersson, L., Doolan, P., Feldman, N., Fredette, A. and B. [2] Andersson, L., Doolan, P., Feldman, N., Fredette, A., and B.
Thomas, "LDP Specification", RFC 3036, January 2001 Thomas, "LDP Specification", RFC 3036, January 2001.
[3] Mogul, J. and S. Deering, "Path MTU Discovery", RFC 1191, [3] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191,
November 1990 November 1990.
[4] Rosen, E., Tappan, D., Federkow, G., Rekhter, Y., Farinacci, D., [4] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y., Farinacci, D.,
Li, T. and A. Conta, "MPLS Label Stack Encoding", RFC 3032, Li, T., and A. Conta, "MPLS Label Stack Encoding", RFC 3032,
January 2001 January 2001.
[6] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V. and G. [6] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and G.
Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC
3209, December 2001 3209, December 2001.
Informative References 6.2. Informative References
[5] Jamoussi, B., Ed., "Constraint-Based LSP Setup Using LDP", RFC [5] Jamoussi, B., Andersson, L., Callon, R., Dantu, R., Wu, L.,
3212, January 2002 Doolan, P., Worster, T., Feldman, N., Fredette, A., Girish, M.,
Gray, E., Heinanen, J., Kilty, T., and A. Malis, "Constraint-
Based LSP Setup using LDP", RFC 3212, January 2002.
Security Considerations 7. Security Considerations
This mechanism does not introduce any new weaknesses in LDP. It is This mechanism does not introduce any new weaknesses in LDP. It is
possible to spoof TCP packets belonging to an LDP session to possible to spoof TCP packets belonging to an LDP session to
manipulate the LSP MTU, but LDP has mechanisms (see Section 5 of [2]) manipulate the LSP MTU, but LDP has mechanisms to thwart these types
to thwart these types of attacks. of attacks. See Section 5 of [2] for more information on security
aspects of LDP.
IANA Considerations 8. IANA Considerations
A new LDP TLV Type is defined in section 2.4. A Type has to be IANA has allocated 0x0601 as a new LDP TLV Type, defined in Section
allocated by IANA; a number from the range 0x0000 - 0x3DFF is 2.4. See: http://www.iana.org/assignments/ldp-namespaces
requested.
Acknowledgments 9. Acknowledgements
We would like to thank Andre Fredette for a number of detailed We would like to thank Andre Fredette for a number of detailed
comments on earlier versions of the signalling mechanism. Eric Gray, comments on earlier versions of the signalling mechanism. Eric Gray,
Giles Heron and Mark Duffy have contributed numerous useful Giles Heron, and Mark Duffy have contributed numerous useful
suggestions. suggestions.
Authors' Addresses Authors' Addresses
Benjamin Black Benjamin Black
Layer8 Networks Layer8 Networks
EMail: ben@layer8.net EMail: ben@layer8.net
Kireeti Kompella Kireeti Kompella
Juniper Networks Juniper Networks
1194 N. Mathilda Ave 1194 N. Mathilda Ave
Sunnyvale, CA 94089 Sunnyvale, CA 94089
US US
EMail: kireeti@juniper.net EMail: kireeti@juniper.net
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This document and the information contained herein is provided on an The IETF invites any interested party to bring to its attention any
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Acknowledgement: Acknowledgement
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Internet Society. Internet Society.
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