Network Working Group T. Eckert
Internet-Draft Huawei
Intended status: Experimental G. Cauchie
Expires: September 6, 2018 Bouygues Telecom
W. Braun
M. Menth
University of Tuebingen
March 5, 2018
Protection Methods for BIER-TE
draft-eckert-bier-te-frr-03
Abstract
This document proposes protection methods for the BIER-TE
architecture [I-D.ietf-bier-te-arch]. These include 1+1 (live-live)
path/tree [RFC7431] redundancy, 1:1 path/tree protection, as well as
fast reroute (FRR) methods. The latter may protect against link and/
or node failures and leverage infrastructure tunnels, BIER-in-BIER
encapsulation, or header modification for implementation.
In particular, this memo describes FRR for BIER-TE in detail. FRR
for BIER-TE requires support from the BIER-TE controller and the BFRs
that are attached to a link/adjacency for which FRR protection is
desired. FRR relies on the BIER header described in [RFC8279] which
is also used by BIER-TE. It does not require extensions or
modifications to existing BIER-TE tables. However, the presented FRR
procedures need some additional forwarding plane logic on the BFR.
An additional table is needed that carries information about pre-
computed backup paths. When a failure is detected, the information
from this table is used to modify the bitstring in the BIER header
before forwarding a packet over a backup path. To prevent undesired
packet duplication, packets should be tunneled on the backup paths.
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). Note that other groups may also distribute
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and may be updated, replaced, or obsoleted by other documents at any
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time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 6, 2018.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Overview of FRR Mechanisms for BIER-TE . . . . . . . . . . . 3
2.1. Path/Tree Diversity . . . . . . . . . . . . . . . . . . . 3
2.1.1. 1+1 Path/Tree Redundancy . . . . . . . . . . . . . . 3
2.1.2. 1:1 Path/Tree Protection . . . . . . . . . . . . . . 5
2.2. 1:1 Link/Node Protection . . . . . . . . . . . . . . . . 5
2.2.1. Link Protection using Existing Mechanisms . . . . . . 6
2.2.2. Node Protection using Existing Mechanisms . . . . . . 6
2.2.3. Native 1:1 Protection using BIER-in-BIER
Encapsulation . . . . . . . . . . . . . . . . . . . . 7
2.2.4. Native BIER-TE Node and Link Protection . . . . . . . 7
3. FRR Extension for Native 1:1 Protection with BIER-TE . . . . 7
3.1. FRR Key Concepts . . . . . . . . . . . . . . . . . . . . 8
3.2. The BIER-TE Adjacency FRR Table (BTAFT) . . . . . . . . . 9
3.3. FRR in BIER-TE Forwarding . . . . . . . . . . . . . . . . 10
3.4. FRR in the BIER-TE Controller . . . . . . . . . . . . . . 10
3.5. BIER-TE FRR Benefits . . . . . . . . . . . . . . . . . . 11
3.6. Adjustment to the BIER-TE Forwarding Pseudocode . . . . . 11
3.7. Recommendations for Tunneling . . . . . . . . . . . . . . 14
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
6. Change log [RFC Editor: Please remove] . . . . . . . . . . . 14
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
7.1. Normative References . . . . . . . . . . . . . . . . . . 15
7.2. Informational References . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
The BIER-TE architecture is defined in [I-D.ietf-bier-te-arch] and
does not provide any protection mechanisms. However, there are
several approaches to protect multicast traffic against network
failures. This draft gives an overview of 1+1 (live-live) path/tree
redundancy, 1:1 path/tree protection, as well as fast reroute (FRR)
methods including link and node protection. They may leverage either
existing mechanisms with some extensions for BIER-TE, BIER-TE point-
to-multipoint tunnels, or renounce on tunneling at all with the
downside of reduced coverage.
This document describes additions to the BIER-TE architecture that
facilitate FRR for link and node protection using BIER-TE
encapsulation. Similar extensions are needed for node-protection FRR
with existing mechanisms and must be supported by and must be
supported by the BIER-TE controller and BFRs attached to a link/
adjacency for which FRR support is required. The FRR operation
modifies the BIER header to facilitate local bypass of failed
elements. It is possible to add and remove multicast links to the
header, use unicast tunnels, e.g., MPLS tunnels, to implement the
bypass, or to leverage BIER-in-BIER encapsulation.
The BIER-TE FRR method only requires a small set of additional
forwarding entries that are stored in a separate table called the
BTAFT. The entries depend only on the topology and not on the
multicast flows.
2. Overview of FRR Mechanisms for BIER-TE
In the following we give an overview of various protection methods
that may be applied to protect BIER-TE-based multicast trees.
BIER-TE can be combined with a range of mechanisms to provide
resilience in the face of failures such as link or nodes. In this
section, we give an overview of the key options.
2.1. Path/Tree Diversity
2.1.1. 1+1 Path/Tree Redundancy
In 1+1 redundancy, often also called live-live, traffic is sent twice
across the network, path-engineered in a way that no single point of
failure (link or node) is in the path for both copies towards every
single receiver. For point-to-multipoint transmission, this
basically requires disjoint ent-to-end paths. For point-to-
multipoint transmission, distribution structures are needed that
fulfill the earlier mentioned criterion. They usually resemble
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"orthogonal" tree structures. See [BIERFRRANALYSIS] for
illustration. For multicast transmission, 1+1 redundancy can be very
attractive because the cost of dual transmission can often be
negligible vs. the overall bandwidth saving of doing replication in
the network.
Path-engineering for 1+1 redundancy can become quite advanced
depending on the topology - but it does not require any new
functionalities from BIER-TE. It just requires appropriate
engineering and potentially additional application or BIER edge
functions such as traffic duplication at the sender and traffic
deduplication at the receiver.
Consider the following topology example: each sender or receiver has
connections to two BFRs to overcome the failure of either BFR. The
application on the source creates two copies for every packet. It
sends one "a-packet" copy onto its a-link and the other "b-packet"
copy onto its b-link. Snd,Rcvr could be BFIR,BFER or they could send
native multicast and the BFR they connect to are BFIR, BFER.
BIER-TE bitstrings need to be set up for a-packets and b-packets to
pass through the topology counter-circular to each other so that any
individual link or node failure never interrupt both a-packets and
b-packets
Snd1,Rcv1
a-link/ \
/ \
------ BFR1a ---- BFR1b -------
/ \
- BFR2a (RING1) BFR4b -
/ \ / \
Snd2,Rcv2 \ / Snd4,Rcv4
-- BFR2b ---- BFR3a -- BFR3b --- BFR4a ----
/ \ / \
/ Snd3,Rcv3 \
- BFR5a BFR6b -
/ \ (RING2) / \
Snd5,Rcv5 \ / Rcv5
-- BFR5b --- BFR6a --- BFR6b --- BFR6a -----
\ /
Rcv6
The application side in Snd,Rcv needs to be able to eliminate the
duplication resulting from receiving both a-packet and b-packet
copies (unless there is a failure). This is easily done if there is
any encapsulation (such as transport layer) where sequence numbers
are used. Otherwise such a layer has to be added.
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If sender and/or receivers can not support the duplication on the
sending side and/or deduplication on the receiving side, it is easy
to derive variations of these designs in which network ingress/egress
devices take over these rules. The functionality that is least
common in network devices is per-packet deduplication based on
sequence numbers in the packets. Only few network transport service
encapsulations do currently provide sequence numbers, e.g., L2TPv3.
Because the described ingress/egress functionalities are not specific
to BIER-TE but would equally apply to the solution if built with
native IP multicast or RSVP-TE/P2MP, this document does not propose
any further functionality required for this type of solutions.
Compared to RSVP-TE/P2MP, one specific benefit of BIER-TE is that
trees can be optimized without re-signaling solely by the BIER-TE
sender adding/deleting bits representing leaf trees to receivers that
join/leave the content.
2.1.2. 1:1 Path/Tree Protection
If duplicate transmission is not desirable, variations of the above
scheme can be devised where only one copy is sent to each receiver.
Such solutions require receiver feedback to the sender and are
therefore most feasible for a limited receiver set deployment, e.g.,
regional multi-system operator (MSO) distribution networks to hybrid
fiber-coaxial (HFC) headends. For example, by default only the
a-tree could be transmitted, and upon reception failure at any subset
of receivers, the sender would transmit to the subset of the b-tree
covering those receivers. Upon recovery of the a-tree, signaling
from the receiver could equally stop transmission of the b-tree
toward this receiver.
For a more common path utilization across the network in the no-
failure scenario, senders could instead start with 50% receiver
populated a-tree and b-tree as well.
These options heavily depend on the ability to change the set of
receivers in a tree without signaling. The enabling/disabling of
sending to a particular branch of the network can be done within a
single round-trip starting with the signaling of the reception
failure by a receiver.
2.2. 1:1 Link/Node Protection
In this section we discuss the link and node protection for BIER-TE
using existing mechanisms and the native BIER-Te FRR approach.
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2.2.1. Link Protection using Existing Mechanisms
BIER-TE can be used in conjunction with reactive 1:1 link protection
as it is also possible in RSVP-TE/P2MP. When a node sees a failure
on a link, it assumes that the link has failed and uses a pre-
established backup path to get packets to the node on the other side
of the link. In example below, BFR2 would use a pre-established path
via l7,l2,l3,l4 to send packets to BFR3 when it sees a failure of
link1.
l3
------ BFR4 ------- BFR5 ------
/ / \
/ l2 l4 / \ l5
/ / |
BFR1 ---- BFR2 --X-- BFR3 ---- BFR6 --
l7 l1 \ |
\ | l6
\ |
-- BFR7 --
In BIER-TE, this link protection can be done either by using some
pre-existing traffic engineered tunneling mechanisms such as RSVP-TE/
P2P or Segment Routing paths to get packets to BFR3 in the link
failure case. These options do not require enhancements to BIER-TE.
2.2.2. Node Protection using Existing Mechanisms
BFR2 can not distinguish whether link1 or BFR3 fails. It simply
needs to assume one or the other and perform link or node protection.
If it assumes node failure and wants to perform node protection, the
solution becomes more complex. Effectively, BFR2 needs to get the
packets over to BFR5,BFR6 and BFR7 or the subset of those next-next-
hops that is required. Using pre-established p2p backup tunnels
(RSVP-TE/P2P or SR) allows to send just to the required subset of
next-next-hops at the expense of sending the traffic up to three
times across the path consisting of the links l7,l2,l3. The required
subset of next-next-hops consists of the downstream next-next-hops.
Downstream means that the next-next-hops are the direct multicast
children of the next-hop. This is similar to the FRR concept
discussed in Section 3.1. Using a backup RSVP-TE/P2MP tree
eliminates this higher load but would deliver to all next-next-hops
or it would be necessary to set up backup RSVP-TE/P2MP trees for all
possible subsets of next-next-hops (which may not scale well).
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2.2.3. Native 1:1 Protection using BIER-in-BIER Encapsulation
A simpler solution for node protection leverages BIER-in-BIER
encapsulation. In this approach, BFR2 would encapsulate the BIER-TE
packet into another BIER-TE packet whose bitset was pre-built to
carry the packet via l7,l2,l3,l5,l6 to BFR5,BFR6,BFR7 optionally
reducing the bitset based on the bitset of the encapsulated BIER-TE
packet. This document describes this option in Section 3.
If there are no available infrastructure tunnels deployed, then BIER-
in-BIER encapsulation could equally be used for the simple case of
link protection.
2.2.4. Native BIER-TE Node and Link Protection
An even simpler solution is to not encapsulate the BIER-TE packet
into another BIER-TE packet but instead to rewrite the bitstring of
the BIER-TE packet to make the packets get delivered via l2,l3 to
BFR5, via l5 to BFR6 if that is part of the original bitstring and
via l6 to BFR7, if that is part of the original bitstring.
This document specifies the necessary rules for the BIER-TE
forwarding machinery for such bitstring bitstring rewrites to enable
the most lightweight and efficient form of node protection with BIER-
TE.
This solution will not work in all topologies though because the set
of bits necessary to pass the traffic across a backup path/tree may
cause undesired traffic forwarding (duplicates/loops).
3. FRR Extension for Native 1:1 Protection with BIER-TE
In this section, we explain the FRR extension to support native 1:1
protection with BIER-TE. These extensions do not require changes to
the BIER header or to forwarding mechanism. The protection procedure
runs directly before the BIER-TE forwarding procedure.
Note that the FRR extensions require the use of a new table which is
described in Section 3.2. The table is only filled with entries that
depend on the network topology and do not depend on the multicast
flows.
An implementation of BIER-TE FRR based on BIER-in-BIER encapsulation
in the networking programming language P4 is given in [BIER-FRR-P4].
The source code is thoroughly documented and contains examples how
the BIER-TE BIFT and BIER-TE BTAFT tables can be filled.
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3.1. FRR Key Concepts
In this section we use the following example to explain the key
concepts of BIER-TE FRR. The example shows a multicast tree from
BFR1 to BFR2, BFR6, BFR9. The path to BFR2 is represented by the
bits p1, p3 and p4. The bits p1, p6, p7 and the bits p2, p8
represent the path towards BFR6 and BFR 9, respectively. Local_decap
bits for all BFR2,BFR6, and BFR9 are also used.
BFR1-------+
| |
| |
p4 p3 v p1 v p2
BFR2<---BFR3<-----BFR4------BFR5
| | p5 |
| | |
p8 | v p6 v p8
BFR6<-----BFR7-----BFR9
p7 p9 p10
First, we consider that the link from P towards F fails. The failure
can be protected by the backup paths over BFR3->BFR6->BFR7: p3, p8,
p9 (BP1) and BFR5->BFR9->BFR7: p5, p8, p10 (BP2). The use of backup
path BP1 does not cause duplicates. Backup path BP2 would cause
duplicates because the local_decap bit for D2 is still set in
bitstring at P. Two options exist to avoid duplicates.
1. We reset the local_decap bit for D2: This solution prevents the
duplicate packet. However, this method can lead to lost packets
in other examples.
2. We use a tunnel from P to F over D2 to prevent BIER packet
processing at the nodes at the backup path.
Tunnels may be implemented in these two different ways:
1. A remote adjacency represented by a single bit which is a tunnel
in the routing underlay. For an MPLS routing underlay, this can
be implemented using an MPLS label stack. In the example we
would introduce an additional bit,e.g., p11, representing the
tunnel.
2. BIER-in-BIER encapsulation using an additional BIER header with
NextProto = BIER. This methods does not require additional bits
for remote adjacencies compared to remote adjacencies but it
increases the size of the packet header. In this example the new
bitstring contains the bits of BP2 and an additional local_decap
bit for BFR7.
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Now, we consider that BFR7 fails. The backup path must send the
packets to all downstream next next-hops (DS-NNHs), i.e. the next-
hops of the sub-tree rooted of BFR7. BFR4 can identify the DS-NNHs
by checking the bits of interest of the failed node BFR7. BFR6 is
such a node because bit p7 is set. BFR9 is not downstream because
there is no bit of interest from BFR7 to BFR9. Sending packets to
BFR9 would causes duplicates because BFR9 is served using the branch
BFR1->BFR5->BFR9.
Protection against link failures only requires knowledge of the
failed adjacency. Protection against node failures requires
additional knowledge of the downstream nodes of the tree. The
computation of appropriate backup paths, AddBitmasks, ResetBitmasks,
and BitPositions is outside of the scope of this document.
3.2. The BIER-TE Adjacency FRR Table (BTAFT)
The BIER-TE IF FRR Table exists in every BFR that is supporting BIER-
TE FRR. It is indexed by FRR Adjacency Index that is compromised of
the SI and the adjacency. Associated with each FRR Adjacency Index
are the failed BitPosition (F-BP), Downstream BitPosition (DS-BP),
ResetBitmask, and AddBitmask. The table can be configured to enable
different actions for the AddBitMask. Either the table is configured
to apply BIER-in-BIER encapsulation with a new BIER header containing
the AddBitmask as new bitstring or to simply add the bits on the
current bitstring.
---------------------------------------------------------------------
| FRR Adjacency | Failed | Downstream | ResetBitmask | AddBitmask |
| Index | BP | BP | | |
=====================================================================
| 0:1 | 5 | 5 | ..0010000 | ..11000000 |
---------------------------------------------------------------------
...
An FRR Adjacency is an adjacency that is used in the BIFT of the BFR.
The BFR has to be able to determine whether the adjacency is up or
down in less than 50msec. An FRR adjacency can be a
forward_connected adjacency with fast L2 link state Up/Down state
notifications or a forward_connected or forward_routed adjacency with
a fast aliveness mechanism such as BFD. Details of those mechanism
are outside the scope of this architecture.
The FRR Adjacency Index is the index that would be indicated on the
fast Up/Down notifications to the BIER-TE forwarding plane and
enables the selection of appropriate ResetBitmasks and AddBitmasks.
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The failed BitPosition is the BP in the BIFT in which the FRR
Adjacency is used. The downstream BitPosition is required to protect
against node failures to identify the downstream adjacency as
described in Section 3.1. The backup path/tree is constructed of the
individual ResetBitmasks and AddBitmasks of the downstream nodes. To
protect against link failures, the DS-BP field is set equally to the
F-BP field.
3.3. FRR in BIER-TE Forwarding
The BIER-TE forwarding plane receives fast Up/Down notifications of
BIER adjacencies which are used for different SIs. From the failed
BitPosition in the BTAFT entry, it records which BPs are currently
affected (have a down adjacency).
When a packet is received, BIER-TE forwarding checks if it has failed
BPs and matching downstream BitPositions to which it would forward.
If it does, it will remove the ResetBitmask bits from the packets
BitString. Depending on the table configuration it will either add
the AddBitmask bits to the packets BitString or construct a new BIER
header for rerouted packets. Note that the original packet must be
still available for non-affected bitpositions.
Afterwards, normal BIER-TE forwarding occurs, taking the modified
bitstring or the additional BIER header into account. Note that the
information is pre-computed by the controller so that the BFR can
reroute around a failure immediately after its detection.
3.4. FRR in the BIER-TE Controller
The basic rules how the BIER-TE controller would calculate the
ResetBitmask and the AddBitmask are as follows:
1. The BIER-TE controller decides which tunnel mode a BFR uses for
the BTAFT: remote adjacencies or BIER-in-BIER tunneling.
2. The BIER-TE controller determines whether a failure of the
adjacency should be taken to indicate link or node failure. This
is a policy decision.
3. The ResetBitmask has the BitPosition of the failed adjacency.
4. In the case of link protection, the AddBitmask are the segments
forming a path from the BFR over to the BFR on the other end of
the failed link. The path can be formed using remote adjacencies
for tunneling purposes.
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5. In the case of node protection, the AddBitmask are the segments
forming a tree from the BFR over to all necessary downstream BFRs
of the (assumed to be failed) BFR across the failed adjacency.
6. The ResetBitmask is extended with those segments that could lead
to duplicate packets if the AddBitmask is added to possible
bitstrings of packets using the failing BitPosition.
3.5. BIER-TE FRR Benefits
Compared to other FRR solutions, such as RSVP-TE/P2MP FRR, BIER-TE
FRR has two key distinctions
o It maintains the goal of BIER-TE not to establish in-network per
multicast traffic flow state. For that reason, the backup path/
trees are only tied to the topology, but not to individual
distribution trees.
o For the case of a node failure, it allows to build a path
engineered backup tree as opposed to a set of partly overlapping
p2p backup tunnels.
o BIER-in-BIER encapsulation enables backup tunnels in networks that
do not provide a routing layer with tunneling capabilities. It
may simplify network management because additional tunnels (such
as GRE) do not to be setup in the routing layer.
3.6. Adjustment to the BIER-TE Forwarding Pseudocode
We augment the forwarding procedure presented in the BIER-TE draft to
support FRR.
The following procedure computes the ResetBitmasks and AddBitmasks
when an adjacency up/down notification is triggered. The masks can
later be directly applied to the header to facilitate the backup.
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global ResetBitMaskByBT[BitStringLength]
global AddBitMaskByBT[BitStringLength]
global FRRaffectedBP
void FrrUpDown(FrrAdjacencyIndex, UpDown)
{
global FRRAdjacenciesDown
local Idx = FrrAdjacencyIndex
if (UpDown == Up)
FRRAdjacenciesDown &= ~ 2<<(FrrAdjacencyIndex-1)
else
FRRAdjacenciesDown |= 2<<(FrrAdjacencyIndex-1)
for (Index = GetFirstBitPosition(FRRAdjacenciesDown); Index ;
Index = GetNextBitPosition(FRRAdjacenciesDown, Index))
local BP = BTAFT[Index].BitPosition
FRRaffectedBP |= 2<<(Index)
ResetBitMaskByBT[BP] |= BTAFT[Index].ResetBitMask
AddBitMaskByBT[BP] |= BTAFT[Index].AddBitMask
}
The ForwardBierTePacket procedure must be modified by applying the
FRR operations when necessary.
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void ForwardBierTePacket (Packet)
{
// We calculate in BitMask the subset of BPs of the BitString
// for which we have adjacencies. This is purely an
// optimization to avoid to replicate for every BP
// set in BitString only to discover that for most of them,
// the BIFT has no adjacency.
local BitMask = Packet->BitString
Packet->BitString &= ~MyBitsOfInterest
BitMask &= MyBitsOfInterest
// FRR Operations
// Note: this algorithm is not optimal yet for ECMP cases
// it performs FRR replacement for all candidate ECMP paths
local MyFRRBP = BitMask & FRRaffectedBP
for (BP = GetFirstBitPosition(MyFRRNP); BP ;
BP = GetNextBitPosition(MyFRRNP, BP))
BitMask &= ~ResetBitMaskByBT[BP]
BitMask |= ResetBitMaskByBT[BP]
// Replication
for (Index = GetFirstBitPosition(BitMask); Index ;
Index = GetNextBitPosition(BitMask, Index))
foreach adjacency BIFT[Index]
if(adjacency == ECMP(ListOfAdjacencies, seed) )
I = ECMP_hash(sizeof(ListOfAdjacencies),
Packet->Entropy, seed)
adjacency = ListOfAdjacencies[I]
PacketCopy = Copy(Packet)
switch(adjacency)
case forward_connected(interface,neighbor,DNR):
if(DNR)
PacketCopy->BitString |= 2<<(Index-1)
SendToL2Unicast(PacketCopy,interface,neighbor)
case forward_routed([VRF],neighbor):
SendToL3(PacketCopy,[VRF,]l3-neighbor)
case local_decap([VRF],neighbor):
DecapBierHeader(PacketCopy)
PassTo(PacketCopy,[VRF,]Packet->NextProto)
}
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3.7. Recommendations for Tunneling
Recommendations for usage of tunnels for BIER-TE FRR based on the
study in [BIERFRRANALYSIS]:
1. Tunneling SHOULD be used. The study shows that header
modification does not improve coverage in many topologies and may
cause more harm than protection when node failures occur.
2. Using unicast tunnels may cause unnecessary extra load on
overlapping links when protecting against node failures.
Moreover, they require additional bits in the BIER header.
3. BIER-in-BIER encapsulation is the recommended mechanism. It
causes increased header overhead through the encapsulating BIER
header. This may become an issue when the BIER header supports
long bitstrings
4. IANA Considerations
This document requests no action by IANA.
5. Acknowledgements
The authors would like to thank Greg Shepherd, Ijsbrand Wijnands and
Neale Ranns for their extensive review and suggestions.
6. Change log [RFC Editor: Please remove]
03: Updated references, no other conent changes from -02. Refresh
to continue using this document for reference of new work.
Unchanged. Currently unclear if the novel method proposed in this
document is worth pursuing. If not, then we would change the
document to solely document the applicability of pre-existing
methods (and remove new options).
02: Overview of FRR mechanisms feasible for BIER-TE (Eckert)
02: Removed Section "BIER-TE and existing FRR, because it is now
part of "Overview" chapter (Braun)
02: Added recommendation on native BIER-TE FRR with regard to
tunneling options based on a study (Braun)
02: Added P4 implementation of BIER-TE FRR using BIER-in-BIER as
reference.(Braun)
01: Update of author addresses
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00: Initial version based on draft-eckert-bier-arch-03.
7. References
7.1. Normative References
[I-D.ietf-bier-te-arch]
Eckert, T., Cauchie, G., Braun, W., and M. Menth, "Traffic
Engineering for Bit Index Explicit Replication (BIER-TE)",
draft-ietf-bier-te-arch-00 (work in progress), January
2018.
[RFC7431] Karan, A., Filsfils, C., Wijnands, IJ., Ed., and B.
Decraene, "Multicast-Only Fast Reroute", RFC 7431,
DOI 10.17487/RFC7431, August 2015,
<https://www.rfc-editor.org/info/rfc7431>.
[RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
Przygienda, T., and S. Aldrin, "Multicast Using Bit Index
Explicit Replication (BIER)", RFC 8279,
DOI 10.17487/RFC8279, November 2017,
<https://www.rfc-editor.org/info/rfc8279>.
7.2. Informational References
[BIER-FRR-P4]
Braun, W., Hartmann, J., and M. Menth, "Demo: Scalable and
Reliable Software-Defined Multicast with BIER and P4",
IFIP/IEEE International Symposium on Integrated Network
Management (IM), May 2017, <https://atlas.informatik.uni-
tuebingen.de/~menth/papers/Menth17b.pdf>.
[BIERFRRANALYSIS]
Braun, W., Eckert, T., and M. Menth, "Performance
Comparison of Resilience Mechanisms for Stateless
Multicast Using BIER", IFIP/IEEE International Symposium
on Integrated Network Management (IM), May 2017,
<https://atlas.informatik.uni-tuebingen.de/~menth/papers/
Menth17a.pdf>.
Authors' Addresses
Eckert, et al. Expires September 6, 2018 [Page 15]
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Toerless Eckert
Huawei USA - Futurewei Technologies Inc.
2330 Central Expy
Santa Clara 95050
USA
Email: tte+ietf@cs.fau.de
Gregory Cauchie
Bouygues Telecom
Email: GCAUCHIE@bouyguestelecom.fr
Wolfgang Braun
University of Tuebingen
Email: wolfgang.braun@uni-tuebingen.de
Michael Menth
University of Tuebingen
Email: menth@uni-tuebingen.de
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