BESS WG Y. Wang
Internet-Draft ZTE Corporation
Intended status: Standards Track 15 October 2021
Expires: 18 April 2022
Distributed Bump-in-the-wire Use Case
draft-wang-bess-evpn-distributed-bump-in-the-wire-00
Abstract
The Bump-in-the-wire use-case of Section 4.3 of [RFC9136] is a
centerlized inter-subnet forwarding solution. The centerlized inter-
subnet forwarding burdens the DGWs with the L3 traffics among
different subnets inside the same DC.
This draft extends the Bump-in-the-wire use-case of Section 4.3 of
[RFC9136] in order to achieve a distributed inter-subnet forwarding
solution.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on 18 April 2022.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology and Acronyms . . . . . . . . . . . . . . . . 4
2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Problem with Bump-in-the-wire Use-Case . . . . . . . . . 5
3. Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Determining the Aliasing Pathes for RT-5E . . . . . . . . 7
3.2. ACI-specific Overlay Index Extended Community . . . . . . 8
3.3. Constructing IP Prefix Advertisement Route . . . . . . . 10
3.4. Bump-in-the-wire Specific Procedures . . . . . . . . . . 10
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
5. Security Considerations . . . . . . . . . . . . . . . . . . . 13
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.1. Normative References . . . . . . . . . . . . . . . . . . 13
6.2. Informative References . . . . . . . . . . . . . . . . . 14
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
As shown in Figure 1, the Bump-in-the-wire use-case of Section 4.3 of
[RFC9136] is a centerlized inter-subnet forwarding solution. The
centerlized inter-subnet forwarding burdens the DGWs with the L3
traffics among different subnets inside the same DC.
NVE2 DGW1
M2 +-----------+ +---------+ +-------------+
+---TS2(VA)--| (BD-10) |-| |----| (BD-10) |
| ESI23 +-----------+ | | | IRB1\ |
| + | | | (IP-VRF)|---+
| | | | +-------------+ _|_
SN1 | | VXLAN/ | ( )
| | | GENEVE | DGW2 ( WAN )
| + NVE3 | | +-------------+ (___)
| ESI23 +-----------+ | |----| (BD-10) | |
+---TS3(VA)--| (BD-10) |-| | | IRB2\ | |
M3 +-----------+ +---------+ | (IP-VRF)|---+
+-------------+
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Figure 1: Centerlized Bump-in-the-wire Use Case
As shown in Figure 2, the SN1, BD-10, IP-VRF are the same as
Figure 1, except that the TS2, TS3 and ESI23 are not shown in
Figure 2, but they are still there unchanged. Then we add a SBD for
the IP-VRF instance, and each SBD will be configured with an IRB
interface (which is called its SBD IRB). Using this SBD and its SBD
IRB, we can extend the Bump-in-the-wire use case to form a
distributed inter-subnet forwarding solution which will not burden
the DGWs with the L3 traffics among different subnets inside the same
DC.
NVE2 DGW1
+------------+ +---------------+ +------------+
| | | | | |
|(IP-VRF)-(SBD)| |(SBD)-(IP-VRF)|-----+
| / IRB2 | | | | IRB1 | |
+---+(BD-10) | | | +------------+ _+_
| +------------+ | | ( )
SN1| | VXLAN/ | ( WAN )--H1
| NVE3 | GENEVE/ | (___)
| +------------+ | MPLS | DGW2 +
+---+(BD-10) | | | +------------+ |
| \ IRB3 | | | | | |
|(IP-VRF)-(SBD)| |(SBD)-(IP-VRF)|-----+
+------------+ | | | IRB9 |
| | +------------+
NVE8 | |
+------------+ | |
SN8+----+(IP-VRF)-(SBD)| |
| IRB8 | | |
+------------+ +---------------+
Figure 2: Distributed Bump-in-the-wire Use Case
The RT-5 route (say RT5E_SN1) advertised by NVE2/NVE3 for SN1 is the
same as Section 4.3 of [RFC9136] except for the following notable
differentces:
* The route-targets of RT5E_SN1 is set to the export-RT of the SBD.
* The RT-1 route of ESI23 MUST be advertised both for BD-10 and the
SBD, when they are advertised for the SBD, the EVPN label of the
RT-1 per EVI route should be set to the EVPN label of the BD-10,
as if it is advertised for BD-10.
Note that when it is advertised for the SBD, it may use different
RD than it is advertised for BD-10.
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* In order to process the RT5E_SN1 properly, the DGW1 and DGW2
don't have to change its behavior of Section 4.3 of [RFC9136].
But the configurations of DGW1 and DGW2 must be changed, because
that the BD-10 is removed and the SBD takes its place.
Note that to the RT5E_SN1 route, the NVE8 is actually no different
from DGW1 and DGW2. NVE8 is not a DC gateway, but whether NVE8 is a
DC gateway is not awared by NVE1 and NVE2.
But when multiple Bump-in-the-wire are integrated into the same IP-
VRF, the above extension is not enough, the details are discribed in
Section 2.1, thus some extensions are introduced to solve that
problem.
1.1. Terminology and Acronyms
Most of the acronyms and terms used in this documents comes from
[RFC9136] and [I-D.wang-bess-evpn-ether-tag-id-usage] except for the
following:
* VRF AC - An Attachment Circuit (AC) that attaches a CE to an
IP-VRF but is not an IRB interface.
* VRF Interface - An IRB interface or a VRF-AC or an IRC
interface. Note that a VRF interface will be bound to the
routing space of an IP-VRF.
* L3 EVI - An EVPN instance spanning the Provider Edge (PE)
devices participating in that EVPN which contains VRF ACs and
maybe contains IRB interfaces or IRC interfaces.
* IP-AD/EVI - Ethernet Auto-Discovery route per EVI, and the EVI
here is an IP-VRF. Note that the Ethernet Tag ID of an IP-AD/
EVI route may be not zero.
* IP-AD/ES - Ethernet Auto-Discovery route per ES, and the EVI
for one of its route targets is an IP-VRF.
* RMAC - Router's MAC, which is signaled in the Router's MAC
extended community.
* ESI Overlay Index - ESI as overlay index.
* ET-ID - Ethernet Tag ID, it is also called ETI for short in
this document.
* RT-5E - An EVPN Prefix Advertisement Route with a non-reserved
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ESI as its overlay index (the ESI-as-Overlay-Index-style RT-5)
.
* CE-BGP - The BGP session between PE and CE. Note that CE-BGP
route doesn't have a RD or Route-Target.
* CE-Prefix - An IP Prefixes behind a CE is called as that CE's
CE-Prefix.
* ETI-Agnostic BD - A Broadcast Domain (BD) whose data packets
can be received along with any Ethernet Tag ID (ETI). Note
that a broadcast domain of an L2 EVI of VLAN-aware bundle
service interface is a good example of an ETI-Specific BD.
* ETI-Specific BD - A Broadcast Domain (BD) whose data packets
are expected to be received along with a normalized Ethernet
Tag ID (ETI). Note that a broadcast domain of an L2 EVI of
VLAN-bundle or VLAN-based service interface is a good example
of an ETI-Agnostic BD.
* BDI-Specific EADR - When the <ESI, BD> uses BDI-Specific
Ethernet Auto-discovery mode, the only Ethernet A-D per EVI
route of that <ESI, BD> is called as a BDI-Specific EADR in
this draft.
* ACI-Specific EADR - When the <ESI, BD> uses ACI-Specific
Ethernet Auto-discovery mode, the Ethernet A-D per EVI routes
of that <ESI, BD> are called as ACI-Specific EADRs in this
draft.
2. Problem Statement
2.1. Problem with Bump-in-the-wire Use-Case
The Section 4.3 of [RFC9136] defined the Bump-in-the-wire use-case,
where a style (which is called as RT-5E in this draft) of RT-5 routes
(whose overlay index is a non-zero ESI), is used to advertise the IP
prefix of subnet SN1 (see Figure 3). The RT-5E routes (whose IP
prefix is SN1, and ESI is ESI23) of that draft is called as RT5E_SN1
in this draft. And the RT-1 routes (whose ESI is ESI23)
corresponding to the RT5E_SN1 is called as RT1_ESI23 in this draft.
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TS2 NVE2
+--------------+ +---------------+
| | | |
SN7-----(N2-M4)__ | | __(BD-20) |
| \ | IF2 | / |
| =============== +-------+
| __/ | ESI23 | \__ | |
+----- (N1-M2) | + | (BD-10) | | DGW1
| | | | | | +---+-----+
| +--------------+ | +---------------+ | (BD-10) |
| | | \IRB1 |
SN1 | |(IP-VRF) +-+H3
| TS3 | NVE3 | /IBR3 |
| +--------------+ | +---------------+ | (BD-20) |
| | | | | | +---+-----+
+------(N1-M3)__ | + | __(BD-10) | |
| \ | ESI23 | / | |
| =============== +-------+
| __/ | IF3 | \__ |
SN7-----(N2-M5) | | (BD-20) |
| | | |
+--------------+ +---------------+
Figure 3: RT-1 Confliction of Bump-in-the-wire
This network is similar to Figure 7 of Section 4.3 of [RFC9136] with
a few notable exceptions as below.
The NVE2,NVE3,DGW1,IRB1,BD-10,ESI23,TS2,TS3 and SN1 here is the
NVE2,NVE3,DGW1,IRB1,BD-10,ESI23,TS2,TS3 and SN1 there. The N1 here
is the Virtual Appliance (whose VA-MAC is M2/M3 on TS2/TS3) there.
But here we have another Virtual Appliance N2, which are attached to
another Broadcast Domain BD-20. Both BD-10 and BD-20 are integrated
into the same IP-VRF by DGW1. But the subnet SN1 can only be reached
through BD-10, while the subnet SN7 can only be reached through BD-
20.
RT5E_SN1 (whose route-target identifying BD-10) is imported into the
BD-10 at first, although it can be imported into the IP-VRF following
BD-10's IRB interface, RT5E_SN1 will not be imported into the IP-VRF
on other PEs which don't have an instance of BD-10. Thus such PEs
are precluded from connecting to the hosts of SN1 by such rules.
Note that both BD-10 and BD-20 are L2 EVIs of VLAN-based Service
Interfaces.
The solution for this problem is decribed in Section 3.4.
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3. Solutions
3.1. Determining the Aliasing Pathes for RT-5E
In this case, the RT-1 per EVI routes corresponding to that RT-5E
route are selected in the context of a BD.
When selecting corresponding IP-AD/EVI routes for a RT-5E route, the
AOI Extended Community (if it exists) of the RT-5E route is prefered
than the ET-ID of the RT-5E route.
* Using ET-ID to select BDI-Specific EADRs - There may be multiple
Ethernet A-D per EVI routes which all can match the RT-5E's ESI.
In such case, The Ethernet A-D per EVI routes with the same ET-ID
as the RT-5E should be selected.
Note that when the RT-5E's ET-ID is X (X!=0), the ET-IDs of the
selected Ethernet A-D per EVI routes (of that RT-5E) should be all
X.
Note that the RT-5E's ET-ID not only just be used to select
Ethernet A-D per EVI routes, but also be encapsulated into data
packets in order to keep compatible with ETI-specific Bump-in-the-
wire use case.
* Using AOI to select ETI-Specific EADRs - There may be multiple
Ethernet A-D per EVI routes which all can match the RT-5E's ESI.
In such case, The Ethernet A-D per EVI routes whose ET-ID are the
same as the RT-5E's AOI should be selected.
Note that when the RT-5E's AOI is Y (Y!=0), the ET-IDs of the
selected Ethernet A-D per EVI routes (of that RT-5E) should be all
Y.
Note that when the RT-5E's ET-ID is not 0, and an AOI is advertised
along with the RT-5E, the Ethernet A-D per EVI routes of that RT-5E
should be selected according to the AOI.
Note that when a data packet is load-balanced according to <ESI,
AOI>, in Bump-in-the-wire use case, it is the RT-5E's ET-ID which
should be encapsulated into the data packet, not the AOI.
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Note that [I-D.sajassi-bess-evpn-ac-aware-bundling] requires the
Presence of Attachment Circuit ID Extended Community MUST be
ignored by non multihoming PEs. It requires the remote PE (non-
multihome PE, e.g. PE3) MUST process MAC route as defined in
[RFC7432]. But the AOI of this case should be used to select ETI-
Specific EADRs. This is non-compatible with the Attachment Circuit
Extended Community, thus the new ACI-Specific Overlay Index
Extended Community is defined.
3.2. ACI-specific Overlay Index Extended Community
A new EVPN BGP Extended Community called Supplementary Overlay Index
is introduced. This new extended community is a transitive extended
community with the Type field of 0x06 (EVPN) and the Sub-Type of TBD.
It is advertised along with EVPN MAC/IP Advertisement Route (Route
Type 2) per [RFC7432] in ACI-Sepecific Ethernet Auto-Discovery mode.
It may also be advertised along with EVPN Prefix Advertisement Route
(Route Type 5) as per [RFC9136]. Generically speaking, the new
extended community must be attached to any routes which are leant
over an <ESI, EVI> of ACI-specific Ethernet Auto-Discovery.
The Supplementary Overlay Index Extended Community is encoded as an
8-octet value as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=0x06 | Sub-Type=TBD | Type |O|Z|F=1| Flags | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ(Cont.) | VLAN2 | VLAN1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Supplementary Overlay Index Extended Community
o F: Format Indicator, its value is always 1 in this draft. Other
values are reserved.
o Type: .
* 0: VLAN-based AC-ID.
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+=====+===========+========+=======+=======+=====+
| No. | Use Cases | Type | VLAN2 | VLAN1 | MBZ |
+=====+===========+========+=======+=======+=====+
| 1 | untag | type 0 | 0 | 0 | 0 |
+-----+-----------+--------+-------+-------+-----+
| 2 | default | type 0 | 0 | FFF | 0 |
+-----+-----------+--------+-------+-------+-----+
| 3 | dot1q | type 0 | 0 | E | 0 |
+-----+-----------+--------+-------+-------+-----+
| 4 | QinQ | type 0 | E | I | 0 |
+-----+-----------+--------+-------+-------+-----+
Table 1: VLAN-based AOIs
Notes:
E : That field is the External VLAN of the AC.
I : That field is the Internal VLAN of the AC.
0 : The tag corresponding to that field is absent.
FFF : The AC is the default subinterface (Section 3.2) of the
corresponding ES.
untag : An untagged subinterface should be matched by that
format.
default : A default subinterface should be matched by that
format. When the AC is a default subinterface, it will
match all the remaining VLAN-tags (which are left over by
other subinterfaces) on its main-interface.
dot1q : A dot1q subinterface should be matched by that format.
QinQ : A QinQ subinterface should be matched by that format.
* 1-15: Reserved.
o O Flag: Overlay Index Flag, this extended community is used as
overlay index.
When type field is 0-1: For ACI-Specific Ethernet auto-discovery
mode, when it is carried along with a RT-2 route, the O Flag should
be set to 1, For BDI-Specific Ethernet auto-discovery, when it is
carried along with a RT-2 route, the O Flag should be set to 0.
When the O Flag is set to 1, this AC-ID is also called as AOI (ACI-
Specific Overlay Index), and the <ESI, AOI> of that RT-2R or RT-5E
should be used to determine ECMP pathes. At the same time, the AOI
should also be used like Attachment Circuit ID Extended Community
too.
Note that only the lowest 8 bits of MBZ field should be used to
select RT-1 per EVI routes. <lowest 8 bits of MBZ, VLAN2, VLAN1>
of a type-0 AOI forms an Ethernet Tag ID of an ACI-Specific EADR.
o Z Flag: Must be zero. Reserved for future use, the receiver
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should ignore this extended coummunity if Z flag is not zero at
now.
o Flags: Reserved for future use. it is set to 0 on advertising, and
ignored on receiving.
Note that although this extended community is similar to the AC-ID
extended community (as per
[I-D.sajassi-bess-evpn-ac-aware-bundling]), we can assume that they
may be of different Sub-Types because that they have different
behaviors.
3.3. Constructing IP Prefix Advertisement Route
When an IP Prefix Advertisement is advertised, The ACI-Specific SOI
extended community is recommanded to be carried along with it, if it
is not clear that whether there will be conflictions among IP A-D per
EVI routes in the future.
Note that the ACI-Specific SOI here is not used to isolate IP address
spaces. It is just used to resolve its ESI overlay index to a proper
IP A-D per EVI route.
The AC-ID extended community can't be considered as a substitute of
the ET-ID. Because that the AC-ID is not the key of IP A-D per EVI
routes, but the ET-ID is.
3.4. Bump-in-the-wire Specific Procedures
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TS2 NVE2
+--------------+ +---------------+
| | | |
SN7-----(N2-M4)__ | | __(BD-20) |
| \ | IF2 | / |
| =============== +-------+
| __/ | ESI23 | \__ | |
+----- (N1-M2) | + | (BD-10) | | DGW8
| | | | | | +---+-----+
| +--------------+ | +---------------+ | (SBD8) |
| | | | |
SN1 | | |IRB8 |
| TS3 | NVE3 | | |
| +--------------+ | +---------------+ |(IP-VRF)-+-+H8
| | | | | | +---+-----+
+------(N1-M3)__ | + | __(BD-10) | |
| \ | ESI23 | / | |
| =============== +-------+
| __/ | IF3 | \__ |
SN7-----(N2-M5) | | (BD-20) |
| | | |
+--------------+ +---------------+
Figure 5: SBD of Bump-in-the-wire
We can assume that maybe neither BD-10 nor BD-20 will be configured
on DGW8, as illustrated in Figure 5. In such case, we assume that a
SBD (Supplementary BD) can be provisoned on DGW8.
The SBD8 is similar to the SBD of Section 4.4.3 of [RFC9136], except
for the following factors:
The SBD8 will import all the RT-5E routes and the RT-1 routes
which are advertised for BD-10 and BD-20 (and other such BDs of
Bump-in-the-wire use cases) by the NVEs of that DC, But the SBD8
don't import other EVPN routes. and it don't have to advertise
any EVPN routes (e.g. IMET route) because there are no hosts
(even the IP address of IRB8 will not be provisoned in this case)
in the SBD.
Note that DGW3 will advertise the IP prefixes of the IP-VRF using its
own EVPN label and route-targets. It don't have to expect any data
packets to be received from such SBD.
The route advertisement behavior of NVE2 and NVE3 should also be
changed:
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* ACI-specific ethernet auto-discovery mode should be used when NVEs
advertise the RT-1 routes of Bump-in-the-wire use case. Otherwise
the RT-1 routes from BD-10 and BD-20 will conflict with each
other, because that both BD-10 and BD-20 are of VLAN-based
Servcice Interface.
* ACI-specific Overlay Index extended community should be advertised
along with the RT-5E routes. Thus the ET-ID of these RT-5E routes
can be set to zero because that BD-10 and BD-20 are ETI-agnostic
BDs.
Note that the combination of <ESI, AOI> will be used to select the
corresponding RT-1 per EVI routes for these RT-5E routes by SBDs
of other PEs.
The RT-5E routes (for the CE-prefixes behind each BD) should be
advertised follows Section 3.3. Note that the IP-ETI, EADR-ETI
and IP-ACI should be determined by the outgoing AC per each CE-
prefix's VA MAC. The IP-ETI is set to the BD-ID of that outgoing
AC's BD. Given that <AC, BD> is ACI-Specific EAD mode, the IP-ACI
is the AOI extended comunity for that <AC, BD>, and the EADR-ETI
is the same value as the IP-ACI.
* The MAC addresses of IRB interfaces of each BD (e.g. BD-10 and
BD-20) should be the same as the SBD IRB interfaces of the same L3
EVI, otherwise the source MAC may be not expected to be learnt by
the CE-side L2 switches.
Note that although the NVEs of the original Bump-in-the-wire don't
have an IP-VRF instance, it will be no difficult for the RT5E_SN1
and RT1_ESI23 are used when there is an IP-VRF (where SN9 is
learnt by a CE-BGP session) and IRBs on each of the NVEs. In such
case, maybe it will be better for the NVEs to advertise its IRB
(e.g. BD-10's IRB) MAC along with RT1_ESI23 (which is for BD-10)
in order to indicate DGW8 to encapsulate that MAC as source MAC.
By doing so, there will be no need for SBDs, thus the RT-5E routes
and RT-1 per EVI routes can be advertised and imported using the
IP-VRF's route-targets. The RT-1 per EVI routes (whose MPLS label
identifies that BD) can be advertised along with both BD's RT and
IP-VRF's RT. thus the amount of RT-1 per EVI routes will not be
increased.
Note that in Bump-in-the-wire use cases, the EVPN label that is
encapsulated by DGW1/DGW3 for NVE2 or NVE2 will be a label that
identifies a L2 EVI. So when the BD is an ETI-Specific BD, the IP-
ETI MUST be encapsulated into the ethernet header of the data
packets. Otherwise such data packets won't be received by that BD.
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Note that in Bump-in-the-wire use cases, even if the BD is a MPLS
EVPN BD, PE3 should send data packets to NVE2/NVE3 along with the
overlay ethernet header (whose SA is the SBD IRB's MAC address),
because the Bump-in-the-wire use case is actually a special EVPN IRB
use case. Otherwise NVE2/NVE3 can't decapsulate the data packets
properly.
Note that in such case, the RT-5E routes technically can be directly
imported into the IP-VRF identified by its route-target. only if
there would be no more than one SBD in a specified IP-VRF. In
original Bump-in-the-wire use-case, if there would be no more than
one BD in a specified IP-VRF, the the RT-5E routes technically can be
directly imported into the IP-VRF identified by its route-target
(which is determined by policy, because a RT-5E route itself will be
learnt by policy too, according to [RFC9136]). For backward
comptibility with such implementations, the ET-ID (if it is not zero)
of these RT-5E routes may be used to selected RT-1 per EVI routes
from the only BD of that IP-VRF, and in such case it should be
encapsulated into the ethernet header (in VXLAN EVPN) of the
corresponding data packets, because that the RT-1 per EVI routes of
Bump-in-the-wire use case are advertised for BD-10, and BD-10 may use
VLAN-aware bundle service interface according to [RFC9136].
The ESIs of these RT-5E routes are used to selecte RT-1 per EVI
routes in the context of a BD, as described in [RFC9136]. When the
ESIs of RT-5E routes are used to selected RT-1 per EVI routes in the
context of an IP-VRF, it seems that this is not explicitly described
in [RFC9136].
4. IANA Considerations
A new transitive extended community Type of 0x06 and Sub-Type of TBD
for EVPN Supplementary Overlay Index Extended Community needs to be
allocated by IANA.
5. Security Considerations
TBD.
6. References
6.1. Normative References
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Internet-Draft Bump-in-the-wire SBD October 2021
[I-D.sajassi-bess-evpn-ac-aware-bundling]
Sajassi, A., Brissette, P., Mishra, M., Thoria, S.,
Rabadan, J., and J. Drake, "AC-Aware Bundling Service
Interface in EVPN", Work in Progress, Internet-Draft,
draft-sajassi-bess-evpn-ac-aware-bundling-04, 11 July
2021, <https://datatracker.ietf.org/doc/html/draft-
sajassi-bess-evpn-ac-aware-bundling-04>.
[I-D.sajassi-bess-evpn-ip-aliasing]
Sajassi, A., Badoni, G., Warade, P., Pasupula, S., Drake,
J., and J. Rabadan, "EVPN Support for L3 Fast Convergence
and Aliasing/Backup Path", Work in Progress, Internet-
Draft, draft-sajassi-bess-evpn-ip-aliasing-02, 8 June
2021, <https://datatracker.ietf.org/doc/html/draft-
sajassi-bess-evpn-ip-aliasing-02>.
[RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based
Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432, February
2015, <https://www.rfc-editor.org/info/rfc7432>.
[RFC9135] Sajassi, A., Salam, S., Thoria, S., Drake, J., and J.
Rabadan, "Integrated Routing and Bridging in Ethernet VPN
(EVPN)", RFC 9135, DOI 10.17487/RFC9135, October 2021,
<https://www.rfc-editor.org/info/rfc9135>.
[RFC9136] Rabadan, J., Ed., Henderickx, W., Drake, J., Lin, W., and
A. Sajassi, "IP Prefix Advertisement in Ethernet VPN
(EVPN)", RFC 9136, DOI 10.17487/RFC9136, October 2021,
<https://www.rfc-editor.org/info/rfc9136>.
6.2. Informative References
[I-D.wang-bess-evpn-arp-nd-synch-without-irb]
Wang, Y. and Z. Zhang, "ARP/ND Synching And IP Aliasing
without IRB", Work in Progress, Internet-Draft, draft-
wang-bess-evpn-arp-nd-synch-without-irb-08, 1 September
2021, <https://datatracker.ietf.org/doc/html/draft-wang-
bess-evpn-arp-nd-synch-without-irb-08>.
[I-D.wang-bess-evpn-ether-tag-id-usage]
Wang, Y., "Ethernet Tag ID Usage Update for Ethernet A-D
per EVI Route", Work in Progress, Internet-Draft, draft-
wang-bess-evpn-ether-tag-id-usage-03, 26 August 2021,
<https://datatracker.ietf.org/doc/html/draft-wang-bess-
evpn-ether-tag-id-usage-03>.
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Internet-Draft Bump-in-the-wire SBD October 2021
[I-D.wz-bess-evpn-vpws-as-vrf-ac]
Wang, Y. and Z. Zhang, "EVPN VPWS as VRF Attachment
Circuit", Work in Progress, Internet-Draft, draft-wz-bess-
evpn-vpws-as-vrf-ac-02, 28 August 2021,
<https://datatracker.ietf.org/doc/html/draft-wz-bess-evpn-
vpws-as-vrf-ac-02>.
Author's Address
Yubao Wang
ZTE Corporation
No.68 of Zijinghua Road, Yuhuatai Distinct
Nanjing
China
Email: wang.yubao2@zte.com.cn
Wang Expires 18 April 2022 [Page 15]