TRILL Working Group Tissa Senevirathne
Internet Draft CISCO
Intended status: Standard Track Janardhanan Pathangi
Updates: 6325 DELL
Jon Hudson
Brocade
October 2, 2013
Expires: April 2014
Coordinated Multicast Trees (CMT) for TRILL
draft-ietf-trill-cmt-02.txt
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other documents
at any time. It is inappropriate to use Internet-Drafts as
reference material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
This Internet-Draft will expire on March 2, 2009.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
Senevirathne Expires April 2, 2014 [Page 1]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
carefully, as they describe your rights and restrictions with
respect to this document. Code Components extracted from this
document must include Simplified BSD License text as described in
Section 4.e of the Trust Legal Provisions and are provided without
warranty as described in the Simplified BSD License.
Abstract
TRILL facilitates loop free connectivity to non-TRILL legacy
networks via choice of an Appointed Forwarder for a set of VLANs.
Appointed Forwarder provides load sharing based on VLAN with an
active-standby model. Mission critical operations such as High
Performance Data Centers require active-active load sharing model.
Active-Active load sharing model can be accomplished by representing
any given non-TRILL legacy network with a single virtual RBridge.
Virtual representation of the non-TRILL legacy network with a single
RBridge poses serious challenges in multi-destination RPF (Reverse
Path Forwarding) check calculations. This document specifies
required enhancements to build Coordinated Multicast Trees (CMT)
within the TRILL campus to solve related RPF issues. CMT provides
flexibility to RBridges in selecting desired path of association to
a given TRILL multi-destination distribution tree.
Table of Contents
1. Introduction...................................................3
1.1. Scope and Applicability...................................5
1.2. Contributors..............................................5
2. Conventions used in this document..............................5
2.1. Acronyms..................................................5
3. The AFFINITY sub-TLV...........................................6
4. Multicast Tree Construction and Use of Affinity Sub-TLV........6
4.1. Update to RFC 6325........................................7
4.2. Announcing virtual RBridge nickname.......................8
4.3. Affinity Sub-TLV Capability...............................8
5. Theory of operation............................................9
5.1. Distribution Tree provisioning............................9
5.2. Affinity Sub-TLV advertisement............................9
5.3. Affinity sub-TLV conflict resolution......................9
5.4. Ingress Multi-Destination Forwarding.....................10
5.4.1. Forwarding when n < k...............................10
5.5. Egress Multi-Destination Forwarding......................11
5.5.1. Traffic Arriving on an assigned Tree to RBk-RBv.....11
5.5.2. Traffic Arriving on other Trees.....................11
5.6. Failure scenarios........................................11
5.6.1. Edge RBridge RBk failure............................11
Senevirathne Expires April 2, 2014 [Page 2]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
5.7. Backward compatibility...................................12
6. Security Considerations.......................................12
7. IANA Considerations...........................................13
8. References....................................................13
8.1. Normative References.....................................13
8.2. Informative References...................................14
9. Acknowledgments...............................................14
Appendix A. Change History.......................................15
1. Introduction
TRILL (Transparent Interconnection of Lots of Links) presented in
[RFC6325] and other related documents, provides methods of utilizing
all available paths for active forwarding, with minimum
configuration. TRILL utilizes IS-IS (Intermediate System to
Intermediate System) as its control plane and uses a TRILL header
with hop count.
[RFC6325], [6327bis] and [RFC6439] provide methods for
interoperability between TRILL and Legacy networks. [RFC6439],
provide an active-standby solution, where only one of the RBridges
on a link with end stations is in the active forwarding state for
end station traffic for any given VLAN. The RBridge in active
forwarding state for any given VLAN is referred to as the Appointed
Forwarder (AF). All frames ingressed into a TRILL network via the
Appointed Forwarder are encapsulated with the TRILL header with a
nickname held by the ingress AF RBridge. Due to failures, re-
configurations and other network dynamics, the Appointed Forwarder
for any set of VLANs may change. RBridges maintain forwarding tables
that contain destination MAC address and VLAN to egress RBridge
binding. In the event of AF change, forwarding tables of remote
RBridges may continue to forward traffic to the previous AF and that
traffic may get discarded at the egress, causing traffic disruption.
Mission critical applications such as High Performance Data Centers
require resiliency during failover. The active-active forwarding
model minimizes impact during failures and maximizes the available
network bandwidth. A typical deployment scenario, depicted in Figure
1, which may have either End Stations and/or Legacy bridges attached
to the RBridges. These Legacy devices typically are multi-homed to
several RBridges and treat all of the uplinks as a single Multi-
Chassis Link Aggregation (MC-LAG) bundle. The Appointed Forwarder
designation presented in [RFC6439] requires each of the edge
RBridges to exchange TRILL hello packets. By design, an MC-LAG does
not forward packets received on one of the member ports of the MC-
LAG to other member ports of the same MC-LAG. As a result the AF
Senevirathne Expires April 2, 2014 [Page 3]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
designation methods presented in [RFC6439] cannot be applied to
deployment scenario depicted in Figure 1.
An active-active load-sharing model can be implemented by
representing the edge of the network connected to a specific edge
group of RBridges by a single virtual RBridge. Each virtual RBridge
MUST have a nickname unique within its TRILL campus. In addition to
an active-active forwarding model, there may be other applications
that may requires similar representations.
Sections 4.5.1 and 4.5.2 of [RFC6325] as updated by [clearcor]
specify distribution tree calculation and RPF (Reverse Path
Forwarding) check calculation algorithms for multi-destination
forwarding. These algorithms strictly depend on link cost and parent
RBridge priority. As a result, based on the network topology, it may
be possible that a given edge RBridge, if it is forwarding on behalf
of the virtual RBridge, may not have a candidate multicast tree that
the edge RBridge can forward traffic on because there is no tree for
which the virtual RBridge is a leaf node from the edge RBridge.
In this document we present a method that allows RBridges to specify
the path of association for real or virtual child nodes to
distribution trees. Remote RBridges calculate their forwarding
tables and derive the RPF for distribution trees based on the
distribution tree association advertisements. In the absence of
distribution tree association advertisements, remote RBridges derive
the SPF (Shortest Path First) based on the algorithm specified in
section 4.5.1 of [RFC 6325].
Other applications, beside the above mentioned active-active
forwarding model, may utilize the distribution tree association
framework presented in this document to associate to distribution
trees through a preferred path.
This proposal requires presence of multiple multi-destination trees
within the TRILL campus and updating all the RBridges in the network
to support the new Affinity sub-TLV (Section 3. ). It is expected
that both of these requirements will be met as they are control
plane changes, and will be common deployment scenarios. In case
either of the above two conditions are not met RBridges MUST
support a fallback option for interoperability. Since the fallback
is expected to be a temporary phenomenon till all RBridges are
upgraded, this proposal gives guidelines for such fallbacks, and
does not mandate or specify any specific set of fallback options.
Senevirathne Expires April 2, 2014 [Page 4]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
1.1. Scope and Applicability
This document specifies an Affinity sub-TLV to solve associated RPF
issues at the active-active edge. Specific methods in this document
for making use of the Affinity sub-TLV are applicable where multiple
RBridges are connected to an edge device through multi-chassis link
aggregation or to a multiport server or some similar arrangement
where the RBridges cannot see each other's Hellos.
This document DOES NOT provide other required operational elements
to implement active-active edge solution, such as methods of multi-
chassis link aggregation. Solution specific operational elements are
outside the scope of this document and will be covered in solution
specific documents. (See, for example [TRILLPN].)
Examples provided in this document are for illustration purposes
only.
1.2. Contributors
The work in this document is a result of much passionate discussions
and contributions from following individuals. Their names are listed
in alphabetical order:
Ayan Banerjee, Dinesh Dutt, Donald Eastlake, Mingui Zhang, Radia
Perlman, Sam Aldrin, Shivakumar Sundaram and Zhai Hongjun.
2. 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 [RFC2119].
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying [RFC2119] significance.
2.1. Acronyms
MC-LAG: . Multi-Chassis Link Aggregation is a solution specific
extension to [8021AX], that facilitates connecting group of links
from an originating device (A) to group discrete devices (B). Device
(A) treats, all of the links in a given Multi-Chassis Link
Aggregation bundle as a single logical interface and treats all
devices in Group (B) as a single logical device for all forwarding
purposes. Device (A) does not forward packets receive on Multi-
Senevirathne Expires April 2, 2014 [Page 5]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
Chassis Link bundle out of the same Multi-Chassis link bundle. Figure
1 depicts a specific use case example.
CE : Classical Ethernet device, that is a device that performs
forwarding based on 802.1Q bridging. This also can be end-station or
a server.
RPF: Reverse Path Forwarding. See section 4.5.2 of [RFC6325].
3. The AFFINITY sub-TLV
Association of an RBridge to a multi-destination distribution tree
through a specific path is accomplished by using a new IS-IS sub-
TLV, the Affinity sub-TLV.
The AFFINITY sub-TLV appears in Router capability TLVs that are
within LSP PDUs, as described in [6326bis] which specifies the code
point and data structure for the Affinity sub-TLV.
4. Multicast Tree Construction and Use of Affinity Sub-TLV
Figure 1 and Figure 2 below show the reference topology and a
logical topology using CMT to provide active-active service.
-------------------
/ \
| |
| TRILL Campus |
| |
\ /
--------------------
| | |
----- | --------
| | |
+------+ +------+ +------+
| | | | | |
|(RB1) | |(RB2) | | (RBk)|
+------+ +------+ +------+
|..| |..| |..|
| +----+ | | | |
| +---|-----|--|----------+ |
| +-|---|-----+ +-----------+ |
MC- | | | +------------------+ | |
LAG--->(| | |) (| | |) <- MC-LAG
Senevirathne Expires April 2, 2014 [Page 6]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
+-------+ . . . +-------+
| CE1 | | CEn |
| | | |
+-------+ +-------+
Figure 1 Reference Topology
------------------ Sample Multicast Tree (T1)
/ \
| | |
| TRILL Campus | o RBn
| | / | \
\ / / | ---\
--------------------- RB1o o o
| | | | RB2 RBk
| | | ---------- |
| | | oRBv
+------+ +------+ +------+
| | | | | |
|(RB1) | |(RB2) | | (RBk)|
+------+ +------+ +------+
|..| |..| |..|
| +----+ | | | |
| +---|--|--|-------------+ |
| +-|---|--+ +--------------+ |
MC- | | | +------------------+ | |
LAG--->(| | |) (| | |) <- MC-LAG
+-------+ . . . +-------+
| CE1 | | CEn |
| | | |
+-------+ +-------+
Figure 2 Example Logical Topology
4.1. Update to RFC 6325
Section 4.5.1 of [RFC6325], is updated as below:
Senevirathne Expires April 2, 2014 [Page 7]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
Each RBridge that desires to be the parent RBridge for child Rbridge
RBy in a multi-destination distribution tree x announces the
desired association using an Affinity sub-TLV. The child RBridge RBy
is specified by its nickname (or one of its nicknames if it hold
more than one).
When such an Affinity sub-TLV is present, the association specified
by the affinity sub-TLV MUST be used when constructing the multi
destination distribution tree except in case of conflicting Affinity
sub-TLV which are resolved as specified in Section 5.3. In the
absence of such an Affinity sub-TLV, or if there are any RBRidges in
the campus that are do not support Affinity sub-TLV, distribution
trees tree are calculated as specified in the section 4.5.1 of
[RFC6325] as updated by [clearcor]. Section 4.3. below specifies how
to identify RBridges that support Affinity sub-TLV capability.
4.2. Announcing virtual RBridge nickname
Each edge RBridge RB1 to RBk advertises in its LSP virtual RBridge
nickname RBv using the Nickname sub-TLV (6), [6326bis], along with
their regular nickname or nicknames.
It will be possible for any RBridge to determine that RBv is a
virtual RBridge because each RBridge (RB1 to RBk) this appears to be
advertising that it is holding RBv is also advertising an Affinity
sub-TLV asking that RBv be its child in one or more trees.
Virtual RBridges are ignored when determining the distribution
tree roots for the campus.
All RBridges outside the edge group assume that multi-destination
packets with ingress nickname RBv might use any of the distribution
trees that any member of the edge group is advertising that it might
use.
4.3. Affinity Sub-TLV Capability.
RBridges that announce the TRILL version sub-TLV [6326bis] and set
the Affinity capability bit (Section 7. ) support the Affinity sub-
TLV and calculation of multi-destination distribution trees and RPF
checks as specified herein.
Senevirathne Expires April 2, 2014 [Page 8]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
5. Theory of operation
5.1. Distribution Tree provisioning
Let's assume there are n distribution trees and k edge RBridges in
the edge group of interest.
If n >= k
Let's assume edge RBridges are sorted in numerically ascending
order by SystemID such that RB1 < RB2 < RBk. Each Rbridge in the
numerically sorted list is assigned a monotonically increasing
number j such that; RB1=0, RB2=1, RBi=j and RBi+1=j+1.
Assign each tree to RBi such that tree number { (tree_number) %
k}+1 is assigned to RBridge i for tree_number from 1 to n. where n
is the number of trees and k is the number of RBridges considered
for tree allocation.
If n < k
Distribution trees are assigned to RBridges RB1 to RBn, using the
same algorithm as n >= k case. RBridges RBn+1 to RBk do not
participate in active-active forwarding process on behalf of RBv.
5.2. Affinity Sub-TLV advertisement
Each RBridge in the RB1..RBk domain advertises an Affinity TLV for
RBv to be its child.
As an example, let's assume that RB1 has chosen Trees t1 and tk+1 on
behalf of RBv.
RB1 advertises affinity TLV; {RBv, Num of Trees=2, t1, tk+1.
Other RBridges in the RB1..RBk edge group follow the same procedure.
5.3. Affinity sub-TLV conflict resolution
In TRILL, multi-destination distribution trees are built outward
from the root. If an RBridges RB1 advertises an Affinity sub-TLV
with an AFFINITY RECORD that asks for RBridge RBroot to be its child
in a tree rooted at RBroot, that AFFINITY RECORD is in conflict with
TRILL distribution tree root determination and MUST be ignored.
Senevirathne Expires April 2, 2014 [Page 9]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
If an RBridge RB1 advertises an Affinity sub-TLV with an AFFINITY
RECORD that's ask for nickname RBn to be its child in any tree and
RB1 is not adjacent to a real or virtual RBridge RBn, that AFFINITY
RECORD is in conflict with the campus topology and MUST be ignored.
If different RBridges advertise Affinity sub-TLVs that try to
associate the same virtual RBridge as their child in the same tree
or trees, those Affinity sub-TLVs are in conflict for those trees.
The nicknames of the conflicting RBridges are compared to identify
which RBridge holds the nickname that is the highest priority to be
a tree root, with the System ID as the tie breaker
The RBridge with the highest priority to be a tree root will retain
the Affinity association. Other RBridges with lower priority to be a
tree root MUST stop advertising their conflicting Affinity sub-TLV,
re-calculate the multicast tree affinity allocation, and, if
appropriate, advertise a new non-conflict Affinity sub-TLV.
Similarly, remote RBridges MUST honor the Affinity sub-TLV from the
RBridge with the highest priority to be a tree root (use system-ID
as the tie-breaker in the event of conflicting priorities) and
ignore the conflicting Affinity sub-TLV entries advertised by the
RBridges with lower priorities to be tree roots.
5.4. Ingress Multi-Destination Forwarding
If there is at least one tree on which RBv has affinity via RBk,
then RBk performs the following operations, for multi-destination
frames received from a CE node:
1. Flood to locally attached CE nodes subjected to VLAN and multicast
pruning.
2. Ingress in the TRILL header and assign ingress RBridge nickname
as RBv. (nickname of the virtual RBridge).
3. Forward to one of the distribution trees, tree x in which RBv is
associated with RBk
5.4.1. Forwarding when n < k
If there is no tree on which RBv can claim affinity via RBk
(Probably because the number of trees n built is less than number
of RBridges k announcing the affinity sub-TLV), then RBk MUST fall
back to one of the following
1. This RBridge should stop forwarding frames from the CE nodes,
and should mark that port as disabled. This will prevent CE
Senevirathne Expires April 2, 2014 [Page 10]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
nodes from forwarding data on to this RBridge, and only use
those RBridges which have been assigned a tree - -OR-
2. This RBridge tunnels multi-destination frames received from
attached native devices to an RBridge RBy that has an assigned
tree. The tunnel destination should forward it to the TRILL
network, and also to its local access links . (The mechanism
of tunneling and handshake between the tunnel source and
destination are out of scope of this specification and may be
addressed in future documents).
Above fallback options may be specific to active-active forwarding
scenario. However, as stated above, Affinity sub-TLV may be used in
other applications. In such event the application SHOULD specify
applicable fallback options.
5.5. Egress Multi-Destination Forwarding
5.5.1. Traffic Arriving on an assigned Tree to RBk-RBv
Multi-destination frames arriving at RBk on a Tree x, where RBk has
announced the affinity of RBv via x, MUST be forwarded to CE members
of RBv that are in the frame's VLAN. Forwarding to other end-nodes
and RBridges that are not part of the network represented by the RBv
virtual RBridge MUST follow the forwarding rules specified in
[RFC6325].
5.5.2. Traffic Arriving on other Trees
Multi-destination frames arriving at RBk on a Tree y, where RBk has
not announced the affinity of RBv via y, MUST NOT be forwarded to CE
members of RBv. Forwarding to other end-nodes and RBridges that are
not part of the network represented by the RBv virtual RBridge MUST
follow the forwarding rules specified in RFC6325.
5.6. Failure scenarios
The below failure recovery algorithm is presented only as a
guideline. Implementations MAY include other failure recover
algorithms. Details of such algorithms are outside the scope of this
document.
5.6.1. Edge RBridge RBk failure
Each of the member RBridges of given virtual RBridge edge group is
aware of its member RBridges through configuration or some other
method.
Senevirathne Expires April 2, 2014 [Page 11]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
Member RBridges detect nodal failure of a member RBridge through IS-
IS LSP advertisements or lack thereof.
Upon detecting a member failure, each of the member RBridges of the
RBv edge group start recovery timer T_rec for failed RBrdige RBi. If
the previously failed RBridge RBi has not recovered after the expiry
of timer T_rec, members RBridges perform distribution tree
assignment algorithm specified in section 5.1. Each of the member
RBridges re-advertises the Affinity sub-TLV with new tree
assignment. This action causes the campus to update the tree
calculation with the new assignment.
RBi upon start-up, starts advertising its presence through IS-IS
LSPs and starts a timer T_i. Member RBridges detecting the presence
of RBi start a timer T_j. Timer T_j SHOULD be at least < T_i/2.
(Please see note below)
Upon expiry of timer T_j, member RBridges recalculate the multi-
destination tree assignment and advertised the related trees using
Affinity sub-TLV.
Upon expiry of timer T_i, RBi recalculate the multi-destination tree
assignment and advertises the related trees using Affinity TLV.
Note: Timers T_i and T_j are designed so as to minimize traffic down
time and avoid multi-destination packet duplication.
5.7. Backward compatibility
Implementations MUST support backward compatibility mode to
interoperate with pre Affinity sub-TLV RBRidges in the network. Such
backward compatibility operation MAY include, however is not limited
to, tunneling and/or active-standby modes of operations.
Example:
Step 1. Stop using virtual RBridge nickname for traffic ingressing
from CE nodes
Step 2. Stop performing active-active forwarding. And fall back to
active standby forwarding, based on locally defined policies.
Definition of such policies is outside the scope of this document
and may be addressed in future documents.
6. Security Considerations
In general, the RBridges in a campus are trusted routers and the
authenticity of their link state information (LSPs) and link local
Senevirathne Expires April 2, 2014 [Page 12]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
PDUs (Hellos, etc.) can be enforced using regular IS-IS security
mechanisms [IS-IS] [RFC5410]. This including authenticating the
contents of the PDUs used to transport Affinity sub-TLVs.
The particular Security Considerations involve with different
applications of the Affinity sub-TLV will be covered in the
document(s) specifying those applications.
For general TRILL Security Considerations, see [RFC6325].
7. IANA Considerations
IANA is requested to allocate a capability bit for ''Affinity
Supported'' in the TRILL-VER sub-TLV. ''Affinity Supported'' capability
bit and Affinity sub-TLV are specified and allocated in [6326bis].
8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC5310] Bhatia, M., et.al. ''IS-IS Generic Cryptographic
Authentication'', RFC 5310, February 2009.
[RFC6325] Perlman, R., et.al. ''RBridge: Base Protocol
Specification'', RFC 6325, July 2011.
[6327bis] Eastlake, D. et.al., ''RBridge: Adjacency'', draft-eastlake-
trill-rfc6327bis, Work in Progress, July 2011.
[RFC6439] Eastlake, D. et.al., ''RBridge: Appointed Forwarder'', RFC
6439, November 2011.
[6326bis] Eastlake, D. et.al., ''Transparent Interconnection of Lots
of Links (TRILL) Use of IS-IS'', draft-eastlake-isis-
rfc6326bis, Work in Progress, December 2011.
[clearcor] Eastlake, D. et.al., ''TRILL: Clarifications, Corrections,
and Updates'', draft-ietf-trill-clear-correct, Work in
Progress, July 2011.
Senevirathne Expires April 2, 2014 [Page 13]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
[IS-IS] ISO/IEC, ''Intermediate System to Intermediate System Routing
Information Exchange Protocol for use in Conjunction with
the Protocol for Providing the Connectionless-mode Network
Service (ISO 8473)'' ISO/IEC 10589:2002.
8.2. Informative References
[RFC6165] Banerjee, A. and Ward, D. ''Extensions to IS-IS for Layer-2
Systems'', RFC 6165, April 2011.
[RFC4971] Vasseur, JP. et.al ''Intermediate System to Intermediate
System (IS-IS) Extensions for Advertising Router
Information'', RFC 4971, July 2007.
[TRILLPN] Zhai,H., et.al ''RBridge: Pseudonode Nickname'', draft-hu-
trill-pseudonode-nickname, Work in progress, November
2011.
[8021AX] IEEE, ''Link Aggregration'', IEEE Std 802.1AX-2008, November
2008.
[8021Q] IEEE, ''Media Access Control (MAC) Bridges and Virtual
Bridged Local Area Networks'', IEEE Std 802.1Q-2011,
August, 2011
9. Acknowledgments
Authors wish to extend their appreciations towards individuals who
volunteered to review and comment on the work presented in this
document and provided constructive and critical feedback. Specific
acknowledgements are due for Anoop Ghanwani, Ronak Desai, and Varun
Shah. Very special Thanks to Donald Eastlake for his careful review
and constructive comments.
This document was prepared using 2-Word-v2.0.template.dot.
Senevirathne Expires April 2, 2014 [Page 14]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
Appendix A. Change History.
From -01 to -02:
Replaced all references to ''LAG'' with references to Multi-Chassis
(MC-LAG) or the like.
Expanded, Security Considerations section.
Assorted editorial changes.
Senevirathne Expires April 2, 2014 [Page 15]
Internet-Draft Coordinated Multicast Trees for TRILL October 2013
Authors' Addresses
Tissa Senevirathne
Cisco Systems
375 East Tasman Drive,
San Jose, CA 95134
Phone: +1-408-853-2291
Email: tsenevir@cisco.com
Janardhanan Pathangi
Dell/Force10 Networks
Olympia Technology Park,
Guindy Chennai 600 032
Phone: +91 44 4220 8400
Email: Pathangi_Janardhanan@Dell.com
Jon Hudson
Brocade
130 Holger Way
San Jose, CA 95134 USA
Email: jon.hudson@gmail.com
Senevirathne Expires April 2, 2014 [Page 16]
