SAVI in an EVPN network
draft-levyabegnoli-bess-evpn-savi-02
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Eric Levy-Abegnoli , Pascal Thubert , Ratko Kovacina | ||
| Last updated | 2024-03-03 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
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| Send notices to | (None) |
draft-levyabegnoli-bess-evpn-savi-02
BESS E. Levy-Abegnoli
Internet-Draft P. Thubert
Intended status: Informational R. Kovacina
Expires: 4 September 2024 Cisco Systems
3 March 2024
SAVI in an EVPN network
draft-levyabegnoli-bess-evpn-savi-02
Abstract
Source Address Validation procedures have been specified in the SAVI
Working Group and provide a set of mechanisms and state machines to
verify Source Address ownership. The main mechanisms are described
in RFC6620 and RFC7513.
RFC7432 and furthermore RFC9161 specify how an EVPN network could
learn and distribute IP addressess. RFC9161 describes a mechanism by
which the PE can proxy some ND messages based on this information.
In this document, we review how these two sets of specifications and
underlying mechanisms can interact to provide Source Address
Validation in an EVPN network.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
[RFC2119].
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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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."
This Internet-Draft will expire on 4 September 2024.
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Copyright Notice
Copyright (c) 2024 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 (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. SAVI background . . . . . . . . . . . . . . . . . . . . . . . 4
4. Deployment models . . . . . . . . . . . . . . . . . . . . . . 6
5. DHCP assigned addresses . . . . . . . . . . . . . . . . . . . 8
5.1. SAVI-DHCP background . . . . . . . . . . . . . . . . . . 8
5.2. Interactions between RFC7513 and EVPN . . . . . . . . . . 9
6. SLAAC and other IPv6 addresses . . . . . . . . . . . . . . . 9
6.1. SAVI-FCFS background . . . . . . . . . . . . . . . . . . 9
6.2. Interactions between SAVI-FCFS and EVPN . . . . . . . . . 9
6.2.1. Address not found . . . . . . . . . . . . . . . . . . 11
6.2.2. Address found in EVPN table, remote not active . . . 11
6.2.3. Address found in EVPN table, remote active . . . . . 13
6.3. IPv4 address considerations . . . . . . . . . . . . . . . 14
6.4. Interaction with SAVNET considerations . . . . . . . . . 14
7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 15
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 15
11. Normative References . . . . . . . . . . . . . . . . . . . . 15
12. Informative References . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
[RFC6620] describes a mechanism that provides Source Address
Validation Improvements (SAVI) for IPv6 networks based the First Come
First Serve (FCFS) principle, applicable to any type of IPv6
addresses, including those assigned through IPv6 [RFC4291][RFC8200]
Neighbor Discovery (ND) [RFC4861] Stateless Address Autoconfiguration
(SLAAC) [RFC4862]. According to that specification, an IPv6 entry
freshly snooped on a SAVI device needs to reach the “VALID“ state
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before traffic sourced with it can be forwarded.
Another SAVI specification, [RFC7513], describes a similar mechanism
for addresses assigned by DHCPv6/DHCPv4 server. Again, traffic
sourced which such addresses can only be forwarded when the address
state is “BOUND”.
Section 10 of "BGP MPLS-Based Ethernet VPN" [RFC7432] (EVPN)
indicates that a Provider Edge (PE) router may learn IP addresses and
advertise them to other PEs. EVPN allows PEs to execute a proxy ARP/
ND function that is further detailed in "Operational Aspects of Proxy
ARP/ND in Ethernet Virtual Private Network" [RFC9161]. According to
section 3.2 of [RFC9161], IPv6 addresses should be learnt by snooping
Neighbor Advertisements (NA), then advertised in an EVPN MAC/IP
Advertisement route, and finally used on remote PEs to perform said
proxy ARP/ND function.
Assuming one would want to perform Source Address Validation in an
EVPN network, two models can be deployed:
1. the SAVI function runs on SAVI switches not integrated with PEs
2. the SAVI function is integrated with the PEs
These two models are reviewed in Section 4. Corresponding
interactions between SAVI and EVPN are reviewed as well in this
document.
2. Acronyms
This document uses the following abbreviations:
CE: Customer Edge (router)
DAD: Duplicate Address Detection
NA: Neighbor Advertisement (message)
ND: Neighbor Discovery (protocol)
NDP: Neighbor Discovery Protocol
NS: Neighbor Solicitation (message)
PE: Provider Edge (router)
VLAN: Virtual Local Area Network
VxLAN: Virtual Extensible LAN
EVPN: Ethernet Virtual Private Network
VTEP: VXLAN Tunnel EndPoint (node)
BGP: Border Gateway Protocol
SAVI-PE: A PE that integrates SAVI functionality
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3. SAVI background
As specified in the [RFC7039] SAVI instance enforces the hosts' use
of legitimate IP source addresses and to verify that the source
address used in data packets actually belongs to the originator of
the packet following three-step model:
1. Identify which IP source addresses are legitimate for a host,
based on monitoring packets exchanged by the host.
2. Bind a legitimate IP address to the host's "binding anchor" which
must be verifiable in every packet that the host sends.
3. Enforce that the IP source addresses in packets match the binding
anchors to which they were bound.
SAVI devices form a perimeter separating trusted and untrusted
regions of a network. As specified in [RFC6620] and [RFC7513], only
validated addresses can inject traffic over the trusted perimeter.
protection perimeter
+- - - - - - - - - - - - - - - - - - - - - - -+
| |
| trusted perimeter |
| +- - - - - - - - - - - - - - - - - + |
| | | |
| | | |
+-------+ | +--+---+ +--+---+ | +-------+
| | | | SAVI | | SAVI | | | |
|Client | | | | L2-Network | | | |Client |
| | | |device| |device| | | |
+-------+ | +--+---+ +--+---+ | +-------+
| | | |
| +- - - - - - - - - - - - - - - - - + |
| |
+- - - - - - - - - - - - - - - - - - - - - - -+
Figure 1: SAVI network
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According to [RFC6620], any address, used as the source of a packet
or showing up as a target of a Neighbor Advertisement (NA) or a
target of a DAD Neighbor Solicitation (NS), which is not locally
known and validated, is treated as a TENTATIVE address. Validation
process is initiated with a DAD NS (Duplicate Address Detection
Neighbor Solicitation) message with this address in the target field
originated by the SAVI device and broadcasted to any validated or
trusted port. A response received implies a duplication and/or IP
theft [B] and on the contrary, no response allows to progress the
state of the address from TENTATIVE to VALID [A].
+-------+ +---------+ +---------+ +-------+
|Client1| | SAVI1 | | SAVI2 | |Client2|
| | | | | | | |
+-----+-+ +---------+ +---------+ +--+----+
| | | |
| | | |
(*) |data, src=IP | |IP: VALID |
+-------------->|IP not found | |
| | | |
| IP:TENTATIVE| | |
| | | |
| | l2-multicast DAD NS | |
| | target=IP | |
+- | +---------------------->|DAD NS |
| | | +--------------->|
A | wait TENT_LT | |
| | | | |
| | | | |
| | IP: VALID| |IP: NO_BIND |
+- | | | |
DAD NS
+- | +---------------------->|DAD NS |
| | | NA, target=IP +--------------->|
B | |<---------------------------------------|
| | | | |
| | | | |
| | IP: NO_BIND |IP: VALID |
+- | Theft logging | |
(*) Any packet, including a DAD. For DAD and NA, src is found in target
field
Figure 2: SAVI flow
Note that a SAVI device stores only local entries (client facing)
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Sequence goes like this for A:
1. Data sourced with S is received on the ingress SAVI instance. An
entry for S is created in TENTATIVE state.
2. A DAD is built with target=S and broadcasted to all SAVI
instances.
3. Only instances that have the entry "S" in VALID state or trusted
ports forward the DAD.
4. In the absence of a response from Client, the state of the "S"
entry at the ingress SAVI progresses to VALID.
For B, after step 3 Client responds to DAD with an NA (dst=all
nodes).
5. Upon receiving the NA, the ingress SAVI instance move the entry
to NO_BIND and does not allow traffic from this source to be
forwarded.
As described in step 3, only instances that have the entry "S" in
VALID state or trusted ports forward the DAD.
4. Deployment models
In model 1, a SAVI device is inserted between client (host or CE) and
PE (or VTEP). This first model is straight forward and does not
require any additional specification. It is presented in Figure 3.
The SAVI devices operate as a verification perimeter between
untrusted clients (CEs or Hosts) and PEs (or VTEPs). As specified in
[RFC6620] and [RFC7513], only validated addresses can inject traffic
over the trusted perimeter. The mechanisms to validate addresses are
specified in these two RFCs. Note that IPv6 DAD NS (IP source is set
to the unspecified address, see section section-2.5.2 of [RFC4291] ),
used by SAVI for validation, can still be forwarded by EVPN but are
not used by EVPN proxy for learning. Therefore, as long as an
address is not validated by SAVI, it remains unknown by EVPN.
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protection perimeter
+- - - - - - - - - - - - - - - - - - - - - - -+
| |
| trusted perimeter |
| +- - - - - - - - - -+ |
| | | |
| | L3 NETWORK | |
| | VTEP VTEP | |
+-------+ | +------+ ++------+ +------++ +------+ | +-------+
| | | | SAVI | | | | | | SAVI | | | |
|HOST/CE| | | | |EVPN/PE| |EVPN/PE| | | | |HOST/CE|
| | | |device| | | | | |device| | | |
+-------+ | +------+ ++------+ +------++ +------+ | +-------+
| | | |
| | | |
| | | |
| | | |
| +- - - - - - - - - -+ |
| |
| |
+- - - - - - - - - - - - - - - - - - - - - - -+
Figure 3: Deployment model 1
In this model, the SAVI device and the PE/VTEP can also be colapsed
into the same box referenced as a SAVI-PE. The injection happens
over an API between SAVI instance and EVPN rather than over a
physical wire. Furthermore, only validated sources are learnt per
section 3.2 of [RFC9161].
In model 2, SAVI Instance is integrated with te EVPN PE/VTEP, It is
presented in Figure 4. In this model it is possible and even
desirable to leverage the knowledge of remote IP entries stored in
the VTEP EVPN tables to make SAVI validation process more efficient.
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protection perimeter
+- - - - - - - - - - - - - - - - - -- - -- - +
| |
| trusted perimeter |
| +- - - -- - - - - - -+ |
| | | |
| | L3 NETWORK | |
| SAVI-PE | | SAVI-PE |
+-------+ | +--------+-+------+ +------+-+--------+ | +-------+
| | | |SAVI | | | | SAVI | | | |
|HOST/CE| | | | EVPN | | EVPN | | | |HOST/CE|
| | | |instance| | | |instance| | | |
+-------+ | +--------+-+------+ +------+-+--------+ | +-------+
| | | |
| | | |
| | | |
| | | |
| +- - - - ---- - - - -+ |
| |
| |
+- - - - - - - - - - - - - - - - - - - - - - +
protection perimeter
Figure 4: Deployment model 2
The next section review interactions between SAVI and EVPN for
different type of addresses
5. DHCP assigned addresses
5.1. SAVI-DHCP background
The "SAVI Solution for DHCP" [RFC7513] specification describes a
mechanism that provides source address validation for IPv6 networks
where addresses are assigned by DHCPv6 server. The address
validation is achieved by snooping DHCPv6 address assignments, which
is known as DHCP Snooping, or validating discovered address with the
DHCP server which is described as Data Snooping process. Both
processes are described in detail in [RFC7513].
During DHCP Snooping process and according to associated state
machine, an IP entry freshly snooped on a SAVI device progresses from
NO_BIND to BOUND.
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5.2. Interactions between RFC7513 and EVPN
The whole DHCP address assignment procedure is performed using IPv6
Link-Local addresses, which are expected to be VALID prior to the
beginning of this process. The DHCP server or relay can then be
located anywhere in the EVPN network without the DHCP messages being
blocked by SAVI. EVPN itself does not learn from DHCP, so until the
address is assigned, DAD completed and the host have sent an NA
(response to a lookup or unsolicited NA), EVPN is not aware of the
assigned address. After the NA is sent, the address can be learnt by
EVPN, stored locally by the EVPN proxy-ND, and distributed by BGP per
[RFC9161].
Source validation of DHCP assigned addresses in EVPN is described in
"EVPN First Hop Security" [I-D.sajassi-bess-evpn-first-hop-security]
6. SLAAC and other IPv6 addresses
6.1. SAVI-FCFS background
According to [RFC6620], any address, used as the source of a packet
or showing up as a target of a Neighbor Advertisement (NA) or a
target of a DAD Neighbor Solicitation (NS), which is not locally
known and validated, is treated as a TENTATIVE address and a DAD NS
(Duplicate Address Detection Neighbor Solicitation) message with this
address in the target field is originated by the SAVI device and
broadcasted to any validated or trusted port. A response received
implies a duplication and/or IP theft and on the contrary, no
response allow to progress the state of the address from TENTATIVE to
VALID.
6.2. Interactions between SAVI-FCFS and EVPN
Main interactions are listed below:
* Sources not validated by SAVI are not learnt nor distributed by
EVPN: SAVI does not allow NA to be forwarded (model 1) or signaled
(model 2) to EVPN.
* During the validation process for a Source, SAVI (ingress)
originates a broadcast DAD, with target set to "Source" and
forwards (model 1) or signals (model 2) it to EVPN, which delivers
it to remote SAVI devices (over the wire or an API). Only SAVI
devices that have a local validated entry or a trusted interface
forward the DAD to enable the target to defend itself.
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* In case a response is sent by one of the DAD recipients, it is a
broadcast NA (to "all-nodes"), processed by SAVI (egress). The
source is expected to be a SAVI validated source, and as such,
delivered from (egress) SAVI to EVPN for delivery to all VTEPs and
finally to (ingress) SAVI to complete the validation process of
the target "Source".
* The first NA sent by this Source triggers EVPN proxy learning and
EVPN distribution to all VTEPs per [RFC9161].
In model 2 where SAVI is co-located with EVPN table, upon starting
the validation process for an address, SAVI MAY perform a lookup into
EVPN table, where entry can be 1) not found, 2) local or 3) remote.
If the entry is local, this is an error as it is expected only VALID
entries should be learnt by EVPN ND proxy. The entry in the EVPN
table MUST be deleted.
Other cases are described in the next sections
As described in [RFC6620], when validating a source address that is
not known in the local SAVI table, a multicast DAD NS message is sent
to all remote SAVI instances to check for the presence of this
address on any of these instances. This process can be optimized by
leveraging the content of EVPN tables on VTEPs and "unicast-forward"
the DAD to the known address owner, if any, more in [RFC6085].
Depending on the presence of the address in the EVPN table and if
present, whether the address is active or not, there are three
possible scenarios as described below.
1. Address not found in EVPN table.
2. Address found in EVPN table, remote not active.
3. Address found in EVPN table, remote active.
It is important to note that EVPN table is simply a "helper" for SAVI
verification. It may happen that the entry is not present in the
EVPN table due to following reasons:
* Race condition (BGP did not converge yet for that entry).
* EVPN decided not to distribute it (that may be the case for IPv6
Link-Local addresses on some implementations).
* The entry has not been detected in the network yet.
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If the entry is not present in the EVPN table and not present in the
SAVI table, the verification will fallback on sending a multicast
(l2-broadcast) packet to all remote SAVI-PEs.
Similarly, in the case the EVPN lookup for the IP returns a local
entry, SAVI will also fallback on broadcasting the DAD NS used for
verification to all remote SAVI-PEs. This may happen if EVPN
installs the entry for IP before SAVI get a chance to initiate the
verification process, which could be the case in "loose-mode"
described below.
6.2.1. Address not found
Since the source address that is being validated by SAVI process
might not be present in the EVPN table for reasons described above,
it means it cannot be moved to VALID state directly without
performing validation as per [RFC6620]. It will be created as
TENTATIVE in SAVI, and the verification will fallback on sending a
multicast (l2-broadcast) packet to all remote SAVI-PEs.
In the case when entry is not present in the EVPN table due to race
condition or entry is not distributed by the EVPN, multicast NS DAD
will be converted to unnicast on remote SAVI-PEs before forwarding to
the target. In the case when entry is not detected in the network,
multicast NS DAD will be stopped at remote SAVI-PEs.
Note that to prevent race condition where a host is VALID in the
local SAVI instance but not yet present in the EVPN table, SAVI MAY
signal the entry to EVPN as soon as it becomes VALID.
6.2.2. Address found in EVPN table, remote not active
When the source address that is being validated by SAVI process is
present in the EVPN table, then the multicast NS DAD sent by SAVI can
be "unicast-forwarded" per section 3.4. "Unicast-Forward Sub-
function" of [RFC9161].
If the address is no longer active on the remote location, there will
be no response and the validation process will follow the steps as
specified in [RFC6620] to move the entry to VALID state. Once the
entry is in VALID state, the traffic received from that address will
be forwarded into EVPN network and the IP address will be learned by
the EVPN. This is shown in Figure 5
SAVI instance MAY signal the entry to EVPN as soon as it becomes
VALID.
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Note than, by default, waiting "TENT_LT" (TIMEOUT is TENTATIVE
lifetime - default is 500ms) before moving entry to VALID state will
delay mobility by this amount of time.
Until validation is complete, traffic sourced from IP will be
blocked. It is also expected that EVPN will start the mobility
procedure only at the end of the validation (after TENT_LT) process.
This delay can however be improved in some cases.
If the MACs (bound to IP) are the same on both locations, the EVPN
MAC mobility procedure may start immediately after detection of the
MAC at the new location, and traffic from the IP can be allowed
"optimistically", to the exception of ARP/ND/DHCP messages that could
change the status-quo (mac, dhcp lease, etc.). See case 1 in the
figure below. This is sometimes referred to as "loose mode" as
opposed to "strict mode" (nothing allowed till validation is
complete).
By doing so, traffic will resume to new location as soon as BGP has
re-converged, and in case of an IP-theft, mobility procedure and/or
SAVI validation (whichever completes first) will re-establish the
previous situation (case 2 in the figure below).
If the MAC bound to the IP is different from the one already known,
the MAC will be advertised immediately, but not the IP which will be
delayed by TENT_LT. In this case, traffic from the IP or ARP/ND
traffic announcing the MAC change should also be delayed.
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local PE Remote PE
+------+ +---------+ +---------+ +------+
| HOST | | SAVI-PE | | SAVI-PE | | HOST |
| | | | | | | |
+----+-+ +---------+ +---------+ +--+---+
| | | |
| | | |
(1)data, src=IP | |IP: VALID |
+-------------->|IP:REMOTE IP:LOCAL| |
| | | |
| IP:TENTATIVE| | |
| | | |
| IP:REMOTE | | |
| found in | | |
| EVPN table| | |
| | | |
| | (2)l2-unicast DAD NS | |
| | target=IP | |
| +---------------------->|(3)DAD NS |
| | +--------------->|
| wait TENT_LT | |
| | | |
| | | |
| IP: VALID| | |
| | | |
| | IP: LOCAL |IP:NO_BIND |
| | in EVPN table | |
| | | |
| +--IP BGP advertized-> | |
| | IP:REMOTE| |
Figure 5: Remote not responding - Mobility
6.2.3. Address found in EVPN table, remote active
As in previous section, local SAVI sends the multicast NS DAD to the
known (by EVPN, as a remote entry) target but this time, the target
responds with a multicast NA. The validation process will follow the
steps as specified in [RFC6620] and move the entry to NO_BIND state.
Any NA received on this local SAVI instance from the validating port
will not be signalled to EVPN and will not be learnt by EVPN ND
proxy. This is a IP duplication / theft use case and should be
signalled through logging or by triggering an alarm.
This is shown in Figure 6
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local PE Remote PE
+------+ +---------+ +---------+ +------+
| HOST | | SAVI-PE | | SAVI-PE | | HOST |
| | | | | | | |
+----+-+ +-----+---+ +-----+---+ +--+---+
| | | |
| | | |
| src=IP | |IP: VALID |
+-------------->|IP:REMOTE IP:LOCAL| |
| | | |
| IP:TENTATIVE| | |
| | | |
| IP:REMOTE | | |
| found in | | |
| EVPN table| | |
| | | |
| | (2)l2-unicast DAD NS | |
| | target=IP | |
| +---------------------->|(3)DAD NS |
| | +--------------->|
| | | NA |
| | |<---------------|
| |<----------------------| allowed |
| IP:NO_BIND | | |
| Theft signalled | |
Figure 6: Remote active - IP theft
6.3. IPv4 address considerations
While [RFC6620] does not mention IPv4, a very similar mechanism as
the one described for IPv6 addresses could be used for IPv4. NS DAD
is simply replaced by ARP ACD (Address Conflict Detection) as
specified in [RFC5227] in all previous diagrams.
6.4. Interaction with SAVNET considerations
The Source Address Validation Architecture (SAVA) [RFC5210] proposes
a multi-fence approach that implements SAV at three levels of the
network: access, intra-domain, and inter-domain. As described in
[RFC6620] and [RFC7039] the applicability of FCFS SAVI is limited to
local traffic, to verify if the traffic generated by the hosts
attached to the local link contains a valid source address. The
verification of the source address of the inter-subnet traffic is out
of the scope of FCFS SAVI. Other techniques are recommended to
validate inter-subnet traffic. The scope of the Source Address
Validation in Intra-domain and Inter-domain Networks (SAVNET)
includes the SAV function for both intra-domain and inter-domain
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networks. It identifies the technical gaps and fundamental problems
with current mechanism and techniques, and specifies the practical
requirements for the solution of these problems. In that sense, FCFS
SAVI complements SAVNET and the security level can be increased by
combining these two techniques.
7. Security Considerations
8. IANA Considerations
This specification does not require IANA action.
9. Contributors
10. Acknowledgments
11. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.
[RFC5210] Wu, J., Bi, J., Li, X., Ren, G., Xu, K., and M. Williams,
"A Source Address Validation Architecture (SAVA) Testbed
and Deployment Experience", RFC 5210,
DOI 10.17487/RFC5210, June 2008,
<https://www.rfc-editor.org/info/rfc5210>.
[RFC5227] Cheshire, S., "IPv4 Address Conflict Detection", RFC 5227,
DOI 10.17487/RFC5227, July 2008,
<https://www.rfc-editor.org/info/rfc5227>.
[RFC6620] Nordmark, E., Bagnulo, M., and E. Levy-Abegnoli, "FCFS
SAVI: First-Come, First-Served Source Address Validation
Improvement for Locally Assigned IPv6 Addresses",
RFC 6620, DOI 10.17487/RFC6620, May 2012,
<https://www.rfc-editor.org/info/rfc6620>.
[RFC6085] Gundavelli, S., Townsley, M., Troan, O., and W. Dec,
"Address Mapping of IPv6 Multicast Packets on Ethernet",
RFC 6085, DOI 10.17487/RFC6085, January 2011,
<https://www.rfc-editor.org/info/rfc6085>.
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[RFC7039] Wu, J., Bi, J., Bagnulo, M., Baker, F., and C. Vogt, Ed.,
"Source Address Validation Improvement (SAVI) Framework",
RFC 7039, DOI 10.17487/RFC7039, October 2013,
<https://www.rfc-editor.org/info/rfc7039>.
[RFC7513] Bi, J., Wu, J., Yao, G., and F. Baker, "Source Address
Validation Improvement (SAVI) Solution for DHCP",
RFC 7513, DOI 10.17487/RFC7513, May 2015,
<https://www.rfc-editor.org/info/rfc7513>.
[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>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC9161] Rabadan, J., Ed., Sathappan, S., Nagaraj, K., Hankins, G.,
and T. King, "Operational Aspects of Proxy ARP/ND in
Ethernet Virtual Private Networks", RFC 9161,
DOI 10.17487/RFC9161, January 2022,
<https://www.rfc-editor.org/info/rfc9161>.
[I-D.sajassi-bess-evpn-first-hop-security]
Sajassi, A., Krattiger, L., Ananthamurthy, K., Rabadan,
J., and W. Lin, "EVPN First Hop Security", Work in
Progress, Internet-Draft, draft-sajassi-bess-evpn-first-
hop-security-02, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-sajassi-bess-
evpn-first-hop-security-02>.
12. Informative References
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, DOI 10.17487/RFC4291, February
2006, <https://www.rfc-editor.org/info/rfc4291>.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862,
DOI 10.17487/RFC4862, September 2007,
<https://www.rfc-editor.org/info/rfc4862>.
Authors' Addresses
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Eric Levy-Abegnoli
Cisco Systems, Inc
Emerald Square, Batiment C
rue Evariste Galois
06410 BIOT - Sophia Antipolis
France
Phone: +33 497 23 26 20
Email: elevyabe@cisco.com
Pascal Thubert
Cisco Systems, Inc
Emerald Square, Batiment C
rue Evariste Galois
06410 BIOT - Sophia Antipolis
France
Phone: +33 497 23 26 34
Email: pthubert@cisco.com
Ratko Kovacina
Cisco Systems, Inc
2000 Innovation Dr
Kanata, ON K2K 3E8, Canada ON K2K 3E8
Canada
Phone: +1 613 254 4545
Email: rkovacin@cisco.com
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