Network Working Group L. Yong
Internet Draft W. Hao
D. Eastlake
Category: Standard Track Huawei
A. Qu
J. Hudson
Brocade
Expires: December 2014 June 12, 2014
IS-IS Protocol Extension For Building Distribution Trees
draft-yong-isis-ext-4-distribution-tree-02
Abstract
This document proposes an IS-IS protocol extension for automatically
building bi-directional distribution trees to transport multi-
destination traffic in an IP network.
Status of this document
This Internet-Draft is submitted to IETF in full conformance with
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This Internet-Draft will expire on December 12, 2014.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction...................................................3
1.1. Conventions used in this document.........................4
2. IS-IS Protocol Extension.......................................5
2.1. RTADDR sub-TLV............................................5
2.2. RTADDRV6 sub-TLV..........................................6
2.3. The Group Address Sub-TLV.................................7
3. Procedures.....................................................8
3.1. Distribution Tree Computation.............................8
3.2. Parent Selection..........................................8
3.3. Parallel Local Link Selection.............................9
3.4. Tree Selection for a Group...............................10
3.5. Pruning a Distribution Tree for a Group..................10
3.6. Reverse Path Forwarding Check (RPFC).....................10
3.7. Forwarding Using a Pruned Distribution Tree..............11
3.8. Local Forwarding at Edge Router..........................11
3.9. Distribution Tree across different IGP Levels............12
4. Mobility Support..............................................14
4.1. Listener moves from one edge router to another...........14
4.2. Source host moves from one edge router to another........14
5. Backward Compatibility........................................14
6. Interworking with PIM.........................................14
7. Security Considerations.......................................14
8. IANA Considerations...........................................14
9. Acknowledgements..............................................15
10. References...................................................15
10.1. Normative References....................................15
10.2. Informative References..................................15
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1. Introduction
Computer virtualization and cloud applications motivate the DC
network virtualization technology [NVO3FRWK]. This technology
decouples the end-points networking from the DC physical
infrastructure network in terms of address space and configuration
[NVO3FRWK].
DC network virtualization solutions are required to carry all types
of traffic in today's DC physical networks including multi-
destination traffic. It is also desirable to use an IP network as
the DC underlying network for the overlay virtual networks
[NVO3FRWK].
IP network technology does not yet support multi-destination traffic
forwarding. A variety of Protocol Independent Multicast (PIM)
solutions [RFC4601] [RFC5015] are designed to carry IP multicast
traffic over IP networks. However DC infrastructure for multi-
tenancy application is simple IGP domain where using PIM for
multicast transport has several drawbacks. This is because the PIM
use their own hello protocol and hop-to-hop Join/Leave message so
each router does not have global information about the receivers; in
the PIM, the data packets could be forwarded unnecessarily to the
Rendezvous Point(RP), and then get dropped there when no receiver at
all or the sender and receivers for a multicast group are on the
same branch towards the RP. This can unnecessarily consume network
resources. Furthermore PIM solutions maintain a lot of soft-state,
have intensive CPU utilization, and have additional convergence
time, besides the IGP's, under a failure condition.
Although the PIM protocol is mature and has been deployed in IP
networks, applying PIM to DC IP network that supports the Network
Virtualization Overlays can be an extremely challenging [MCASTISS]
[DCMCAST]. For example, VXLAN [VXLAN] solutions require multicast
support in the underlying network to simulate overlay L2 broadcast
capability, where every edge node in an overlay virtual network (VN)
is a multicast source and receiver. An overlay VN topology may be
sparse and dynamic compared to the underlying IP network topology.
Also a large number of overlay VNs may exist in a DC, which PIM
solutions can't scale to.
Furthermore IP Overlay based network virtualization technology has
been adopted by network vendors to create a VN automatically, self-
healing, multi-service fabric to achieve the goal of a SDN capable
fabric which is open, programmable, and elastic. Within the fabric,
it is a closed IP network carrying all types of traffic, hence
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having one control plane protocol to support both uni-destination
and multi-destination forwarding.
This is the motivation to extend IGP protocol in support multicast
transport so one IGP protocol can support both unicast and multicast
transport. This document uses extensions to the IS-IS protocol to
build a distribution tree for multi-destination traffic transport in
an IP network. A router uses either a Router Capabilities TLV or an
MT Router Capabilities TLV to announce the tree root address and the
multicast groups associated to the tree. With this information,
routers in the IGP can compute rooted distribution trees by using
the link state information, i.e. LSDB, and shortest path algorithm.
Edge routers include information in their LSPs to announce their
multicast group-memberships. Routers perform distribution tree
pruning for each multicast group based on other router's group
membership announcements. A router forwards the multi-destination
traffic along the pruned tree.
In case that edge router needs to get the host membership of a
multicast group, edge routers may use IGMP query messages [RFC3376]
to inform the attached hosts and the hosts use IGMP report message
to response with their interested multicast group(s).
In cases where the solution described in this document applies to
the underlying network that transports overlay virtual networks
[NVO3FRWK], mapping between an overlay multicast group and a
underlying multicast group is necessary. Edge routers further need
to perform packet encapsulation/decapsulation.[NVO3FRWK]
The benefits of this solution are 1) protocol convergence: use
single protocol for both unicast and multicast traffic transport and
get the same convergence time for unicast and multicast traffic. 2)
multi-destination transport simplification: rely on the LSDB for
computing a distribution tree and not run PIM hello protocol. 3)
forwarding efficiency: no need to always forward the traffic to the
RP; 4) better scalability: no need to maintain heavy PIM soft
states. TRILL [RFC6325] has used IS-IS for both single destination
and multi-destination packet transport, which proves the protocol
capability of doing both.
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 RFC-2119 [RFC2119].
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2. IS-IS Protocol Extension
2.1. RTADDR sub-TLV
This is a sub-TLV that is used in either a Router Capabilities TLV
or an MT Capabilities TLV. Each RTADDR sub-TLV contains a root IPv4
address and multicast group addresses that associate to the tree. A
router may use multiple RTADDR sub-TLVs to announce multiple root
addresses and associated multicast groups with each root. RTADDR
sub-TLV format is below.
+-+-+-+-+-+-+-+-+
|subType=RTADDR | (1 byte)
+-+-+-+-+-+-+-+-+
| Length | (1 byte)
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Root IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| RESV | (1 byte)
+-+-+-+-+-+-+-+-+
| Tree Priority | (1 byte)
+-+-+-+-+-+-+-+-+
|Num of Groups | (1 byte)
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group Address (1) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group Mask (1) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| GROUP Address (N) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group Mask (N) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where:
subType: RTADDR (TBD)
Length: variable depending on the number of associated groups
Root IPv4 Address: IPv4 Address for a root
S bit: If set, the rooted tree for single area only. Otherwise,
the rooted tree crosses multiple areas.
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RESV: 3 reserved bits. MUST be sent as zero and ignored on receipt.
Tree Priority: An eight bit unsigned integer where larger
magnitude means higher priority. Zero means no priority.
Num of Groups: the number of group addresses
Group Address: IPv4 Address for the group
Group Mask: multicast group range
One router may be the root for multiple trees. Each tree associates
to a set of multicast groups. In this case, a router encodes
multiple RTADDR sub-TLVs to announce root addresses, one for each
root, in either a Router Capabilities TLV or an MT Capabilities TLV.
The group address/mask in different sub-TLVs can overlap. See
section 3 for detail.
2.2. RTADDRV6 sub-TLV
This sub-TLV is used in an IPv6 network. It has the same format and
usage except that the addresses are in IPv6.
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+-+-+-+-+-+-+-+-+
|subTyp=RTADDRV6| (1 byte)
+-+-+-+-+-+-+-+-+
| Length | (1 byte)
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Root IPv6 Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|RESV | (1 byte)
+-+-+-+-+-+-+-+-+
| Tree Priority | (1 byte)
+-+-+-+-+-+-+-+-+
|Num of Groups | (1 byte)
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Group IPv6 Address (1) +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ MASK(1) +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2.3. The Group Address Sub-TLV
The Group Address TLV and a set of Group Address sub-TLVs are
defined in RFC 7176 [RFC7176]. The GIP-ADDR and GIPV6-ADDR sub-TLVs
are used in this solution. An edge router uses the GIP-ADDR sub-TLV
or GIPV6-ADDR to announce its interested multicast groups. The GIP-
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ADDR sub-TLV applies to an IPv4 network and GIPV6-ADDR sub-TLV for
IPv6 network.
When using a GIP-ADDR or GIPV6-ADDR sub-TLV, the field VLAN-ID MUST
set to zero and be ignored. Other field usage remains the same as
[RFC7176]
3. Procedures
When an operator selects a router as a distribution tree root,
he/she configures the tree root address and associated multicast
groups on the router. A tree root address can be an interface
address or router loopback address. After the configuration, the
router will include a RTADDR sub-TLV, inside either a Router
Capabilities TLV or an MT Capabilities TLV, where the tree root
address and multicast groups are specified. If multiple trees are
configured on the router, multiple RTADDR sub-TLVs are added in one
or more Router Capabilities TLVs or MT Capabilities TLVs to specify
individual tree roots. For IPv4 network, RTADDR sub-TLV is used. For
IPv6, RTADDRV6 sub-TLV is used. Note that the rest of document
specifies the processes for an IPv4 network only. The processes for
an IPv6 network are the same.
Operators may associate one multicast group to more than one tree
for the redundancy purposes and use the tree priority to specify the
primary tree preference. Section 3.2 describes the primary tree
selection.
3.1. Distribution Tree Computation
Upon receiving RTADDR sub-TLVs, routers track the tree roots and
associated multicast groups. When the LSDB stabilizes, routers
calculate all rooted trees according to the LSDB and shortest path
algorithm.
One multicast group may associate to multiple trees. It is important
that all the routers choose the same tree for a multicast group.
Section 3.2 and 3.3 describes the tiebreaking rule for primary tree
selection for a multicast group and parent selection in case of
equal-cost to potential children.
3.2. Parent Selection
It is important, when building a distribution tree, that all routers
choose the same links for the tree. Therefore, when there are equal
costs from a potential child node to possible parent nodes, all
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routers need to use the same tiebreakers. It is also desirable to
allow splitting of traffic on as many links as possible in such
situations. TRILL [RFC6325] achieves this by defining multiple
rooted trees and using the tiebreakers to enable nodes in these
trees to choose different parents. This draft uses the same
tiebreakers as TRILL ([RFC6325] as clarified and updated by section
3.4 and 3.5 of [RFC7180]), and states as follow:
If there are k distribution trees in the network, when each router
computes these trees, the k trees calculated are ordered and
numbered from 0 to k-1 in ascending order according to root IP
addresses.
The tiebreaker rule is: When building the tree number j, remember
all possible equal cost parents for router N. After calculating the
entire "tree" (actually, directed graph), for each router N, if N
has "p" parents, then order the parents in ascending order according
to the 7-octet IS-IS ID considered as an unsigned integer, and
number them starting at zero. For tree j, choose N's parent as
choice (j-1) mod p.
3.3. Parallel Local Link Selection
If there are parallel point-to-point links between two routers, say
R1 and R2, these parallel links would be visible to R1 and R2, but
not to other routers. If this bundle of parallel links is included
in a tree, it is important for R1 and R2 to decide which link to use;
if the R1-R2 link is the branch for multiple trees, it is desirable
to split traffic over as many link as possible. However the local
link selection for a tree is irrelevant to other Routers. Therefore,
the tiebreaking algorithm need not be visible to any Routers other
than R1 and R2.
When there are L parallel links between R1 and R2 and they both are
on K trees. L links are ordered from 0 to L-1 in ascending order of
Circuit ID as associated with the adjacency by the router with the
highest System ID, and K trees are ordered from 0 to K-1 in
ascending order of root IP addresses. The tiebreaker rule is: for
tree k, select the link as choice k mod L.
Note that if multiple distribution trees are configured in a network
or on a router, better load balance among parallel links through the
tie-breaking algorithm can be achieved. Otherwise, if there is only
one tree is configured, then only one link in parallel links can be
used for the corresponding distribution tree. However, calculating
and maintaining many trees is resource consuming. Operators need to
balance between two.
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3.4. Tree Selection for a Group
Routers receive one or more possible multicast group-range-to-tree
mappings. Each mapping specifies a range of multicast groups. It is
possible that a group-range is associated with multiple trees that
may have the same or different priority. When a multicast group-
range associates with more than one tree, all routers have to select
the same tree for the group-range. The tiebreaker rules specified in
PIM [RFC4601] are used. They are:
o Perform longest match on group-range to get a list of trees.
o Select the tree with highest priority.
o If only one tree with the highest priority, select the tree for
the group-range.
o If multiple trees are with the highest priority, use the PIM hash
function to choose one. PIM hash function is described in section
4.1.1 in RFC4601 [RFC4601].
3.5. Pruning a Distribution Tree for a Group
Routers prune the distribution tree for each associated multicast
group, i.e. eliminating branches that have no potential downstream
receivers. Multi-destination packets SHOULD only be forwarded on
branches that are not pruned. The assumption here is that a
multicast source is also a multicast receiver but a multicast
receiver may not be a multicast source.
Routers prune the trees based on the groups specified in GRADD-TLV
from edge routers. Routers maintain a list of adjacency interfaces
that are on the pruned tree for a multicast group. Among these
interfaces, one interface may be toward the tree-root router and
other are toward the egress routers.
3.6. Reverse Path Forwarding Check (RPFC)
The routing transients resulting from topology changes can cause
temporary transient loops in distribution trees. If no precautions
are taken, and there are fork points in such loops, it is possible
for multiple copies of a packet to be forwarded. If this is a
problem for a particular use, a Reverse Path Forwarding Check (RPFC)
may be implemented.
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In this case, the RPFC works by a router determining for each port,
based on the source and destination IP address of a packet, whether
the port is a port that router expects to receive such a packet. In
other words, is there an edge router with reachability to the source
IP address such that, starting at that router and using the tree
indicated by the destination IP address, the packet would have
arrived at the port in question. If so, it is further distributed.
If not, it is discarded. An RPFC can be implemented at some routers
and not at others.
3.7. Forwarding Using a Pruned Distribution Tree
Forwarding a multi-destination packet follows the pruned tree for
the group that the packet belongs to. It is done as follows.
o If the router receives a multi-destination packet with group IP
address that does not associated with any tree, the packet MUST
be dropped.
o Else check if the link that the packet arrives on is one of the
ports in the pruned distribution tree. If not, the packet MUST be
dropped.
o Else perform RPF checking (section 3.5). If it fails, the packet
SHOULD be dropped.
o Else the packet is forwarded onto all the adjacency interfaces in
the list for the group except the interface where the packet
receive.
3.8. Local Forwarding at Edge Router
Upon receiving a multi-destination packet, besides forwarding it
along the pruned tree, an edge router may also need to forward the
packet to the local hosts attached to it. This is referred to as
local forwarding in this document.
The local group database is needed to keep track of the group
membership of the router's directly attached network or host. Each
entry in the local group database is a [group, network/host] pair,
which indicates that the attached network has one or more hosts
belonging to the multicast group. When receiving a multi-destination
packet, the edge router forwards the packet to the network/host that
match the [group, network/host] pair in the local group database.
The local group database is built through the operation of the
IGMPv3 [RFC3376]. When an edge router becomes Designated Router on
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an attached network, say N1, it starts sending periodic IGMPv3 Host
Membership Queries on the network. Hosts then respond with IGMPv3
Host Membership Reports, one for each multicast group to which they
belong. Upon receiving a Host Membership Report for a multicast
group A, the router updates its local group database by
adding/refreshing the entry [Group A, N1]. If at a later time
Reports for Group A cease to be heard on the network, the entry is
then deleted from the local group database. The Designated further
sends the LSP message with GRADDR sub-TLV to inform other routers
about the group memberships in the local group database
A router MUST ignore Host Membership Reports received on those
networks where the router has not been elected Designated Router.
When the solution described in this document applies to the
underlying network that transports overlay virtual networks
[NVO3FRWK], A Designated Router further necessarily maintains the
mapping between an overlay multicast group and a underlying
multicast group, and performs packet encapsulation/descapsulation
upon receiving a packet from host or the underlying network.
Mapping between an overlay multicast group and a underlying
multicast group can be manually configured, automatically generated
by an algorithm, or dynamically informed at a Designated Router. The
same edge router should be selected as the Designated Router for the
overlay multicast group and underlying multicast group that are
associated. The mapping method is beyond the scope of this document.
3.9. Distribution Tree across different IGP Levels
An IGP (Interior Gateway Protocol) network may be designed as a
multi-area network for the scalability, faster-convergence.
Multicast sources and listeners may be in the same or different
areas. The former is a special case of the latter. To support multi-
destination transport over multi-areas, it is necessary to build a
distribution tree across areas and prune the tree based on the
listener locations, i.e. interested edge routers that may reside in
different areas.
For an IS-IS multi-area network, there are level1 and level2 routers
as well as level1/2 (border) routers. A level1 router only has the
router/topology information for its area. A level2 router has
router/topology information for level2 area as well as reachability
information for level1 areas. A border router participates in both
level1 and level2 areas and has the router/topology information for
level2 and all directly attached level1 areas but maintains separate
LSDBs for level2 and each attached level 1 area. Traffic from one
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area to another area must traverse through a border router. It is
possible to have more than one border router between two areas for
resilience.
To build a distribution tree across mutli-areas, an operator can
select a tree-root node for a set of multicast groups. The node can
be in level1 area or level2 area. All the nodes including border
nodes in the area compute the distribution tree as described in
section 3.1-3.4. Border routers automatically select a designated
forwarder for the multicast groups associated to the tree (see
below). The border router selected as designate forwarder (DF)
announces itself as the tree root in the adjacent area if the S bit
in the RTADDR TLV is clear. The nodes in the adjacent area will
compute the distribution tree in the same way. Note that a border
router may be the tree-root in the adjacent area for the multicast
groups that may associate with different trees. If S bit in the
RTADDR TLV is set, the rooted distribution tree is only built in the
area where the root node resides.
The document specifies following additional rules for a border
router that supports the multicast mechanism described here. The
rules apply to the case of the distribution tree across multiple
areas.
If a border router is selected as designated forwarder in adjacent
area for a set of multicast groups, it should perform following:
o It MUST track the group-memberships in its participated areas.
o It MUST send a summary group membership of one area to the
adjacent area as of an edge router.
o It performs the pruning process in each area, respectively, based
on the received group-membership LSPs from that area.
o When receiving multicast traffic from one area, it forwards the
packet along the pruned tree into the adjacent area.
o Optionally performs reverse path forwarding check (RPFC)
If a border router is not selected as the designated forwarder for
the multicast groups, the followings apply:
o It SHOULD NOT propagate the group-membership information of one
area to any other areas. It SHOULD remove the TLV before forwarding
it.
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o It SHOULD NOT forward multicast group traffic to another adjacent
area. It SHOULD discard such traffic.
Selecting a border router as the designated forwarder of multicast
group traffic may be done manually or automatically.
4. Mobility Support
4.1. Listener moves from one edge router to another
When listener moves from one edge router, say E1, to another, say E2.
E1 will detect the host left and send IGMP query for (S, G). Upon
the listener join E2, if E2 has not joined (S,G), E1 should announce
itself as listener to the (S,G) tree.
4.2. Source host moves from one edge router to another
Multicast Tree reaches to every edge router, so source host mobility
is supported naturally. If RPFC is used on a router, the port that
router expects to receive packet may change. Thus, the notification
on source host moves is necessary.
5. Backward Compatibility
If a router does not support the distribution tree function
described in this document, distribution tree computation MUST NOT
include this router. This may result the incomplete tree. An
operator can build a tunnel between two routers, which allows a
single rooted tree to be built. How to build the tunnel is outside
scope of this document.
6. Interworking with PIM
It may be desirable for IS-IS multicast to interwork with PIM on the
same network domain or different domains. The interworking solution
is for further evaluation.
7. Security Considerations
For the further study.
8. IANA Considerations
IANA is requested to assign two new sub-TLV numbers for RTADDR and
RTADDRV6 as specified in Sections 2.1 and 2.2. These sub-TLVs can be
used under both the Router Capability (#242) and MT Capability (#144)
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TLVs. To avoid confusion, each sub-TLV should be assigned the same
sub-Type number under each of these two TLVs.
9. Acknowledgements
Authors like to thank Mike McBride and Linda Dunbar for their
valuable inputs.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC2119, March 1997.
[RFC3376] Cain B., etc, "Internet Group Management Protocol, Version
3", rfc4604, October 2002
[RFC4601] Fenner, B., et al, "Protocol Independent multicast -
Sparse Mode (PIM-SM): Protocol Specification", rfc4601,
August 2006
[RFC5015] Handley, M., et al, "Bidirectional Protocol Independent
Multicast (BIDIR-PIM", rfc5015, October 2007
[RFC5120] Przygienda, T., et al, "M-ISIS: Multi Topology (MT)
Routing in Intermediate System to Intermediate Systems
(IS-ISs)", rfc5120, February 2008
[RFC6325] Perlman, R., et al, "Routing Bridges (RBridges): Base
Protocol Specification", RFC6325, July 2011
[RFC7176] Eastlake 3rd, D., Senevirathne, T., Ghanwani, A., Dutt,
D., and A. Banerjee, "Transparent Interconnection of Lots
of Links (TRILL) Use of IS-IS", RFC 7176, May 2014.
10.2. Informative References
[DCMCAST] McBride, M., Lui, H., "Mutilcast in the Data Center
Overview", draft-mcbride-armd-mcast-overview, 2012
[MCASTISS] Ghanvani, A., "Multicast Issues in Networks Using NVO3",
draft-ghanwani-nvo3-mcast-issues, work in progress
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[NVO3FRWK] Lasserre, M., "Framework for DC Network Virtualization",
draft-ietf-nvo3-framework, work in progress.
[VXLAN] Mahalingam, M., Dutt, D., etc, "VXLAN: A Framework for
Overlaying Virtualized Layer 2 Networks over Layer 3
Networks", draft-mahalingam-dutt-dcops-vxlan, work in
progress
Authors' Addresses
Lucy Yong
Huawei USA
5340 Legacy Drive
Plano, TX 75025 USA
Phone: 469-277-5837
Email: lucy.yong@huawei.com
Weiguo Hao
Huawei Technologies
101 Software Avenue,
Nanjing 210012
China
Phone: +86-25-56623144
Email: haoweiguo@huawei.com
Donald Eastlake
Huawei
155 Beaver Street
Milford, MA 01757 USA
Phone: +1-508-333-2270
EMail: d3e3e3@gmail.com
Andrew Qu
MediaTek
San Jose, CA 95134 USA
Email: laodulaodu@gmail.com
Jon Hudson
Brocade
130 Holger Way
Yong, et al. [Page 16]
Internet-Draft IS-IS Ext. For Distribution Tree June 2014
San Jose, CA 95134 USA
Phone: +1-408-333-4062
Email: jon.hudson@gmail.com
Yong, et al. [Page 17]