TRILL (Transparent Interconnection of Lots of Links): ESADI (End Station Address Distribution Information) Protocol
draft-ietf-trill-esadi-02
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (trill WG) | |
|---|---|---|---|
| Authors | Hongjun Zhai , fangwei hu , Radia Perlman , Donald E. Eastlake 3rd , Olen Stokes | ||
| Last updated | 2013-02-21 | ||
| Replaces | draft-hu-trill-rbridge-esadi | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | plain text htmlized pdfized bibtex | ||
| Reviews |
GENART Last Call review
(of
-06)
On the Right Track
SECDIR Last Call review
(of
-06)
Has Nits
|
||
| Stream | WG state | WG Document | |
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-ietf-trill-esadi-02
TRILL Working Group Hongjun Zhai
INTERNET-DRAFT Fangwei Hu
Intended status: Proposed Standard ZTE
Updates: 6325 Radia Perlman
Intel Labs
Donald Eastlake
Huawei
Olen Stokes
Extreme Networks
Expires: August 21, 2013 February 22, 2013
TRILL (Transparent Interconnection of Lots of Links):
ESADI (End Station Address Distribution Information) Protocol
<draft-ietf-trill-esadi-02.txt>
Abstract
The IETF TRILL (Transparent Interconnection of Lots of Links)
protocol provides least cost pair-wise data forwarding without
configuration in multi-hop networks with arbitrary topologies and
link technologies. TRILL supports multi-pathing of both unicast and
multicast traffic. Devices that implement the TRILL protocol are
called RBridges (Routing Bridges) or TRILL Switches.
ESADI (End Station Address Distribution Information) is an optional
protocol by which a TRILL switch can communicate, in a Data Label
(VLAN or Fine Grained Label) scoped way, end station addresses and
other information to TRILL switches pariticipating in ESADI for the
relevant Data Label. This document updates RFC 6325, specifically
the documentation of the ESADI protocol.
Status of This Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
Distribution of this document is unlimited. Comments should be sent
to the TRILL working group mailing list: <rbridge@postel.org>.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
H. Zhai, et al [Page 1]
INTERNET-DRAFT TRILL: ESADI
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html. The list of Internet-Draft
Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
H. Zhai, et al [Page 2]
INTERNET-DRAFT TRILL: ESADI
Table of Contents
1. Introduction............................................4
1.1 Content and Precedence.................................5
1.2 Terminology............................................5
1.3 Acknowledgements.......................................5
2. ESADI Protocol Overview.................................7
2.1 ESADI Virtual Link....................................10
2.2 ESADI Neighbor Determination..........................11
2.3 ESADI Payloads........................................11
3. ESADI DRB Determination................................13
4. ESADI PDU processing...................................14
4.1 Sending of ESADI PDUs.................................15
4.2 Receipt of ESADI PDUs.................................16
5. End Station Addresses..................................17
5.1 Learning Confidence Level.............................17
5.2 Forgetting End Station Addresses......................17
5.3 Duplicate MAC Address.................................17
6. ESADI-LSP Contents.....................................20
6.1 ESADI Parameter Data..................................20
6.2 MAC Reachability TLV..................................21
6.3 Default Authentication................................22
7. IANA Considerations....................................23
7.1 ESADI Participation and Capability Flags..............23
7.2 TRILL GENINFO TLV.....................................24
8. Security Considerations................................26
Normative references......................................27
Informative References....................................28
Appendix Z: Change History................................29
Z.1 From -00 to -01.......................................29
Z.2 From -01 to -02.......................................29
Authors' Addresses........................................30
H. Zhai, et al [Page 3]
INTERNET-DRAFT TRILL: ESADI
1. Introduction
The IETF TRILL (Transparent Interconnection of Lots of Links)
protocol [RFC6325] provides least cost pair-wise data forwarding
without configuration in multi-hop networks with arbitrary topologies
and link technologies, safe forwarding even during periods of
temporary loops, and support for multi-pathing of both unicast and
multicast traffic. TRILL accomplishes this with the IS-IS
(Intermediate System to Intermediate System) [IS-IS] [RFC1195]
[rfc6326bis] link state routing protocol using a header with a hop
count. The design supports optimization of the distribution of
multi-destination frames and two types of data labeling, VLANs
(Virtual Local Area Networks) and FGLs (Fine Grained Labels,
[RFCfgl]). Devices that implement TRILL are called TRILL switches or
RBridges (Routing Bridges).
There are five ways an RBridge can learn end station addresses, as
described in Section 4.8 of [RFC6325]. The ESADI (End Station
Address Distribution Information) protocol is an optional Data Label
scoped way RBridges can communicate, with each other, information
such as end station addresses and their RBridge of attachment. An
RBridge that is announcing interest in a Data Label MAY use the ESADI
protocol to announce the end station address of some or all of its
attached end stations in that Data Label to other RBridges that are
running ESADI for that Data Label. (In the future, ESADI may also be
used for additional types of information.)
By default, TRILL switches with connected end stations learn
addresses from the data plane when ingressing and egressing native
frames. The ESADI protocol's potential advantages over data plane
learning include the following:
1. Security advantages: (1a) The ESADI protocol can be used to
announce end stations with an authenticated enrollment (for
example enrollment authenticated by cryptographically based EAP
(Extensible Authentication Protocol [RFC3748]) methods via
[802.1X]). (1b) The ESADI protocol supports cryptographic
authentication of its message payloads for more secure
transmission.
2. Fast update advantages: The ESADI protocol provides a fast update
of end stations MAC (Media Access Control) addresses. If an end
station is unplugged from one RBridge and plugged into another,
frames ingressed for that MAC address can be black holed. They
can be sent just to the older egress RBridge that the end station
was connected to until cached address information at some remote
ingress RBridge times out, possibly for tens of seconds or more
[RFC6325].
H. Zhai, et al [Page 4]
INTERNET-DRAFT TRILL: ESADI
MAC address reachability information, some ESADI parameters, and
optionally authentication information are carried in ESADI packets
rather than in the TRILL IS-IS protocol. As described below, ESADI
is, for each Data Label, a virtual logical topology overlay in the
TRILL topology. An advantage of using ESADI over using TRILL IS-IS is
that the end station attachment information is not flooded to all
RBridges through TRILL IS-IS but only to RBridges advertising ESADI
participation for the Data Label in which those end stations occur.
1.1 Content and Precedence
This document updates [RFC6325], the TRILL basic specification,
essentially replacing the description of the ESADI protocol, and
prevails over [RFC6325] where they conflict.
Section 2 is the ESADI protocol overview. Section 3 specifies ESADI
DRB state. Section 4 discusses the processing of ESADI PDUs. Section
5 discusses interaction with other modes of end station address
learning. And Section 6 describes the ESADI-LSP contents.
1.2 Terminology
This document uses the acronyms defined in [RFC6325] and the
following phrase:
Data Label - VLAN or FGL.
FGL - Fine Grained Lable [RFCfgl]
LSP number zero - A Link State PDU with fragment number equal to
zero
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
1.3 Acknowledgements
The authors thank the following, listed in alphabetic order, for
their suggestions and contributions:
H. Zhai, et al [Page 5]
INTERNET-DRAFT TRILL: ESADI
Somnath Chatterjee and Thomas Narten
This document was produced with raw nroff. All macros used were
defined in the source file.
H. Zhai, et al [Page 6]
INTERNET-DRAFT TRILL: ESADI
2. ESADI Protocol Overview
ESADI is a Data Label scoped way for RBridges to announce and learn
end station addresses rapidly and securely. An RBridge that is
announcing participation in ESADI for one or more Data Labels is
called an ESADI RBridge.
ESADI is a separate protocol from the TRILL IS-IS implemented by all
RBridges in a campus. There is a separate ESADI instance for each
Data Label (VLAN or FGL). In essence, for each Data Label, there is a
modified instance of the IS-IS reliable flooding mechanism in which
ESADI RBridges may choose to participate. (These are not the
instances being specified in [RFC6822].) It is an implementation
decision how independent the multiple ESADI instances at an RBridge
are. For example, the ESADI link state database could be in a single
database with a field in each record indicating the Data Label to
which it applies or could be a separate database per Data Label. But
the ESADI update process operates separately for each ESADI instance
and independently from the TRILL IS-IS update process.
ESADI does no routing so there is no reason for pseudo-nodes in ESADI
and none are created. This allows re-purposing one byte of the LSP ID
field to expand the number of possible fragments from 2**8 to 2**16.
In [IS-IS], the "LSP ID" field is 8 bytes. (Actually it is the length
of System ID plus 2, but we will assume a 6-byte System ID.) The top
6 bytes of the LSP ID are the router's System ID, the next byte is
non-zero for pseudo-nodes, and the bottom byte is the fragment
number. In ESADI-LSPs, there is just the System ID followed by two
bytes of fragment number. The same change is made to the LSP ID
field of the Remaining Lifetime TLV which is used in EASDI-CSNP and
ESADI-PSNP. The bottom byte of the ESADI CSNP/PSNP Header Source ID
is always zero.
After the TRILL header, ESADI packets have an inner Ethernet header
with the Inner.MacDA of "All-Egress-RBridges" (formerly called "All-
ESADI-RBridges"), an inner Data Label specifying the VLAN or FGL of
interest, and the "L2-IS-IS" Ethertype followed by the ESADI payload
as shown in Figure 1.
H. Zhai, et al [Page 7]
INTERNET-DRAFT TRILL: ESADI
+--------------------------------+
| Link Header |
+--------------------------------+
| TRILL Data Header |
+--------------------------------+
| Inner Ethernet Addresses |
+--------------------------------+
| Data Label |
+--------------------------------+
| ESADI Payload |
+--------------------------------+
| Link Trailer |
+--------------------------------+
Figure 1. TRILL ESADI Packet Overview
TRILL ESADI packets sent on an Ethernet link are structured as shown
below. The outer VLAN tag will not be present if it was stripped by
an Ethernet port out of which the packet was sent.
H. Zhai, et al [Page 8]
INTERNET-DRAFT TRILL: ESADI
Outer Ethernet Header:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Hop Destination Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Hop Destination Addr. | Sending RBridge Port MAC Addr.|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sending RBridge Port MAC Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ethertype = C-Tag 0x8100 | Outer.VLAN Tag Information |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ethertype = TRILL 0x22F3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TRILL Header: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| V | R |M|Op-Length| Hop Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Egress Nickname | Ingress (Origin) Nickname |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Inner Ethernet Header:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| All-Egress-RBridges |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| All-Egress-RBridges cont. | Origin RBridge MAC Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Origin RBridge MAC Address continued |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLAN or FGL Data Label (4 or 8 bytes) ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ethertype = L2-IS-IS 0x22F4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ESADI Payload (formatted as IS-IS):
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IS-IS Common Header, IS-IS PDU Specific Fields, IS-IS TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Frame Check Sequence:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FCS (Frame Check Sequence) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: ESADI Ethernet Link Packet Format
The Next Hop Destination Address or Outer.MacDA is the All-RBridges
multicast address if the ESADI PDU is being multicast while, if it is
being unicast, the Next Hop Destination Address is the unicast
address of the next hop RBridge. The VLAN for the Outer.VLAN
information will always be the Designated VLAN for the link on which
the packet is sent. The V and R fields will be zero while the M field
will be one unless the ESADI PDU was unicast as discussed below, in
which case the M field will be zero. The Data Label specified will be
the VLAN or FGL to which the ESADI packet applies. The Origin RBridge
MAC Address or Inner.MacSA MUST be a MAC address unique across the
H. Zhai, et al [Page 9]
INTERNET-DRAFT TRILL: ESADI
campus owned by the RBridge originating the ESADI packet, for
example, any of its port MAC addresses if it has any Ethernet ports,
and each RBridge MUST use the same Inner.MacSA for all of the ESADI
packets that RBridge originates.
TRILL ESADI packets sent on a PPP link are structured as shown below
[RFC6361].
PPP Header:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PPP = TNP (TRILL data) 0x005D |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
TRILL Header: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| V | R |M|Op-Length| Hop Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Egress Nickname | Ingress (Origin) Nickname |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Inner Ethernet Header:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| All-Egress-RBridges |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| All-Egress-RBridges cont. | Origin RBridge MAC Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Origin RBridge MAC Address continued |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLAN or FGL Data Label (4 or 8 bytes) ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ethertype = L2-IS-IS 0x22F4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ESADI Payload (formatted as IS-IS):
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IS-IS Common Header, IS-IS PDU Specific Fields, IS-IS TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
PPP Check Sequence:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PPP Check Sequence |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: ESADI PPP Link Packet Format
2.1 ESADI Virtual Link
All transit RBridges forward ESADI packets as if they were ordinary
TRILL Data packets. Because of this forwarding, it appears to an
instance of the ESADI protocol at an RBridge that it is directly
connected by a multi-access virtual link to all other RBridges in the
campus running ESADI for that Data Label. No "routing" computation or
routing decisions ever have to be performed by ESADI. An ESADI
H. Zhai, et al [Page 10]
INTERNET-DRAFT TRILL: ESADI
RBridge merely transmits the ESADI packets it originates on this
virtual link as described for TRILL Data packets in [RFC6325] and
[RFCfgl]. For multicast ESADI packets it may use any distribution
tree that it might use for an ordinary multi-destination TRILL Data
packet. RBridges that do not implement the ESADI protocol, do not
have it enabled, or are not participating for the Data Label of an
ESADI packet do not decapsulate or locally process any TRILL ESADI
packets they receive. Thus the ESADI packets are transparently
tunneled through transit RBridges.
2.2 ESADI Neighbor Determination
The ESADI instance for Data Label X at an RBridge RB1 determines who
its ESADI neighbors are by logically examining the TRILL IS-IS link
state database for RBridges that are data and IS-IS reachable from
RB1 (see Section 2 of [ClearCorrect]) and are announcing their
participation in Data Label X ESADI. When an RBridge RB2 becomes IS-
IS or data unreachable from RB1 or the relevant entries for RB2 are
purged from the core IS-IS link state database, it is lost as a
potential neighbor and also dropped from any ESADI instances. And
when RB2 is no longer announcing participation in Data Label X ESADI,
it ceases to be a neighbor for the Data Label X ESADI instance, these
considerations being Data Label scoped. Because of these mechanisms,
there are no "Hellos" sent in ESADI.
Participation announcement in a VLAN scoped ESADI instance is through
setting a flag bit in the Interested VLANs sub-TLV and announcement
for an FGL scoped ESADI instance is through setting a flag bit in the
Interested Labels sub-TLV [rfc6326bis]. (See Section 7.1)
2.3 ESADI Payloads
TRILL ESADI packet payloads are structured like IS-IS PDUs, except as
indicated below, but are always TRILL encapsulated on the wire as if
they were TRILL Data packets. The information distributed by the
ESADI protocol includes a list of local end station MAC addresses
connected to the originating RBridge and, for each such address, a
one octet unsigned "confidence" rating in the range 0-254 (see
Section 6.2). It is entirely up to the originating RBridge which
locally connected MAC addresses it wishes to advertise via ESADI and
with what confidence. It MAY advertise all, some, or none of such
addresses. In addition, some ESADI parameters of the advertising
RBridge (see Section 6.1) and possibly authenticaiton information
(see Section 6.3) are included. Future uses of ESADI may distribute
H. Zhai, et al [Page 11]
INTERNET-DRAFT TRILL: ESADI
other types of information.
TRILL ESADI-LSPs MUST NOT contain a Data Label ID in their payload.
The Data Label to which the ESADI data applies is the Data Label of
the TRILL Data packet enclosing the ESADI payload. If a Data Label ID
could occur within the payload, it might conflict with that TRILL
Data packet Data Label and could conflict with any future Data Label
mapping scheme that may be adopted [VLANmapping]. If a VLAN or FGL ID
field within an ESADI-LSP PDU does include a value, that field's
contents is ignored.
H. Zhai, et al [Page 12]
INTERNET-DRAFT TRILL: ESADI
3. ESADI DRB Determination
Because ESADI does no adjacency announcement or routing, the ESADI-
DRB never creates a pseudonode. But a DRB is still needed for LSP
synchronization by issuing ESADI-CSNP PDUs and responding to ESADI-
PSNP PDUs.
Generally speaking, the DRB election on the ESADI virtual link (see
Section 2.1) operates similarly to a TRILL IS-IS broadcast link
[RFC6327] with the following exceptions: In the Data Label X ESADI-
DRB election at RB1 on an ESADI virtual link, the candidates are the
local ESADI instance for Data Label X and all remote ESADI instances
at RBridges that (1) are data and IS-IS reachable from RB1
[ClearCorrect], and (2) are announcing in their TRILL IS-IS LSP that
they are participating in ESADI for Data Label X. The winner is the
instance with the highest ESADI Parameter 7-bit priority field with
ties broken by System ID, comparing fields as unsigned integers with
the larger magnitude considered higher priority. "SNPA/MAC address"
is not considered and there is no "Port ID".
H. Zhai, et al [Page 13]
INTERNET-DRAFT TRILL: ESADI
4. ESADI PDU processing
Data Label X ESADI neighbors are usually not connected directly by a
physical link, but are always logically connected by a virtual link
(see Section 2.1). There could be hundreds or thousands of ESADI
RBridges on the virtual link. There are only ESADI-LSP, ESADI-CSNP
and ESADI-PSNP PDUs used in ESADI. In particular, there are no Hello
or MTU PDUs because ESADI does not build a topology and does not do
any routing.
In IS-IS, PDU multicasting is normal on a local link and no effort is
made to optimize to unicast because under the original conditions
when IS-IS was designed (commonly a piece of multi-access Ethernet
cable) any frame made the link busy for that frame time. But in ESADI
what appears to be a simple multi-access link is generally a set of
multi-hop distribution trees that may or may not be pruned. Thus,
transmitting a multicast frame on such a tree can impose a
substantially greater load than transmitting a unicast frame. This
load may be justified if there are likely to be multiple listeners
but may not be justified if there is only one recipient of interest.
For this reason, under some circumstances, ESADI PDUs MAY be TRILL
unicast if it is confirmed that the destination RBridge supports
receiving unicast ESADI PDUs (see Section 6.1).
To support unicasting of ESADI PDUs, Section 4.6.2.2 of [RFC6325] is
replaced with the following:
"4.6.2.2. TRILL ESADI Packets
If M=1, the egress nickname designates the distribution tree. The
packet is forwarded as described in Section 4.6.2.5. In addition,
if the forwarding RBridge is (1) interested in the specified VLAN
or Fine Grained Label, (2) implements the TRILL ESADI protocol,
and (3) ESADI is enabled for that VLAN or Fine Grained Label, the
inner frame is decapsulated and provided to that local ESADI
protocol.
If M=0 and the egress nickname is not that of the receiving
RBridge, the packet is forwarded as for known unicast TRILL Data
in Section 4.6.2.4. If M=0 and the egress nickname is that of the
receiving RBridge and the receiving RBridge supports unicast ESADI
PDUs, then the ESADI packet is decapsulated and processed if it
meets the three numbered conditions in the paragraph above,
otherwise it is discarded."
The references to "4.6.2.2", "4.6.2.4", and "4.6.2.5" above refer to
those sections in [RFC6325].
Section 4.1 describes the sending of ESADI PDUs. Section 4.2 covers
the receipt of ESADI PDUs.
H. Zhai, et al [Page 14]
INTERNET-DRAFT TRILL: ESADI
4.1 Sending of ESADI PDUs
The MTU available to ESADI payloads is at least 24 bytes less than
that available to TRILL IS-IS because of the additional fields
required (2(TRILL Ethertype) + 6(TRILL Header) + 6(Inner.MacDA) +
6(Inner.MacSA) + 4/8(Inner.VLAN/Inner.FGL) bytes). Thus the inner
ESADI payload, starting with the Intradomain Routeing Protocol
Discriminator byte, MUST NOT exceed Sz minus 24 for a VLAN ESADI
instance or Sz minus 28 for an FGL ESDAI instance; however, if a
larger payload is received, it is processed normally. (See [RFC6325]
and [ClearCorrect] for discussions of Sz and MTU.)
An ESADI instance does not transmit any ESADI PDUs if it has zero
EASDI neighbors. When an ESADI instance sees that it has a new
neighbor, its self-originated EASDI-LSP fragments are scheduled to be
sent and MAY be unicast to that neighbor if the neighbor is
announcing in its LSP that it supports unicast ESADI (see Section
6.1). If all the other ESADI instances for the same Data Label send
their self-originated ESADI-LSPs immediately, there may be a surge of
traffic to that new neighbor. So the other ESADI instances should
wait an interval of time before sending the ESADI-LSP to a new
neighbor. The interval time value is up to the device implementation
and is subject to the usual IS-IS timing jitter. One suggestion is
that the interval time can be assigned a random value with a range
based on the ESADI instace DRB priority such ( 2 * (127 - priority) /
128) seconds.
If the ESADI instance believes it is DRB, it multicasts an ESADI-CSNP
periodically (thrice per CSNP Time, see Section 6.1) to keep the link
state database synchronized among its neighbors on the virtual link.
After receiving an ESADI-PSNP PDU, the DRB will multicast the ESADI-
LSPs requested by the ESADI-PSNP on the virtual link.
The multi-hop TRILL multi-destination packet distribution with
Reverse Path Forwarding Check will typically be less reliable than
the single hop link-local LSP synchronization of TRILL IS-IS.
Therefore, for LSP synchronization robustness, in addition to sending
ESADI-CSNPs when it is DRB, an ESADI RBridge SHOULD also transmit an
ESADI-CSNP for an ESADI instance if all of the following conditions
are met:
o it sees one or more ESADI neighbors for that instance, and
o it does not believe it is DRB for the ESADI instance, and
o it has not received or sent an ESADI-CSNP PDUs for the instance
for the CSNP Time (see Section 6.1) of the DRB.
In the case of receiving an ESADI-LSP with a smaller sequence number
than the copy stored in the local EASDI Link State Database the local
ESADI instance will also schedule to multicast the stored copy.
H. Zhai, et al [Page 15]
INTERNET-DRAFT TRILL: ESADI
The format of a unicast ESADI packet is the format of TRILL ESADI
packet, in Section 2 above, except as follows:
o On an Ethernet link, in the Outer Ethernet Header the Outer.MacDA
is the unicast address of the next hop RBridge.
o In the TRILL header, the M bit is set to zero and the Egress
Nickname is the nickname of the destination RBridge.
4.2 Receipt of ESADI PDUs
Because ESADI adjacency is in terms of System ID, all IS-IS PDU
acceptance tests that check that the PDU is from an adjacent system
instead check that the System ID is that of an ESADI neighbor and do
not check either the source Inner or Outer SNPA/MAC.
Because all data reachable ESADI RBridges participating for Data
Label X are adjacent, when RB1 receives an ESADI-CSNP from RB2 and
detects that it has ESADI-LSPs that RB2 is missing, it sets the
transmission flag only for its own ESADI-LSPs that RB2 is missing.
Missing ESADI-LSPs originated by other ESADI RBridges will be
detected by those other ESADI RBridges.
When receiving an ESADI-PSNP PDU, if the local ESADI instance is DRB,
the ESADI-LSP PDUs requested by the ESADI-PSNP will be multicast on
the virtual link.
H. Zhai, et al [Page 16]
INTERNET-DRAFT TRILL: ESADI
5. End Station Addresses
5.1 Learning Confidence Level
The confidence level mechanism allows an RBridge campus manager to
cause certain address learning sources to prevail over others. MAC
address information learned through a registration protocol, such as
[802.1X] with a cryptographically based EAP [RFC3748] method, might
be considered more reliable than information learned through the mere
observation of data frames. When such authenticated learned address
information is transmitted via the ESADI protocol, the use of
authentication in the TRILL ESADI-LSP packets could make tampering
with it in transit very difficult. As a result, it might be
reasonable to announce such authenticated information via the ESADI
protocol with a high confidence, so it would be used in preference to
any alternative learning from data observation.
5.2 Forgetting End Station Addresses
The end station addresses learned through TRILL ESADI protocol should
be forgotten through changes in ESADI-LSPs. The time out of the
learned end station address is up to the originating RBridge that
decides when to remove such information from its ESADI-LSPs (or up to
ESADI protocol timeouts if the originating RBridge becomes
inaccessible).
If RBridge RBn participating in the TRILL ESADI protocol for Data
Label X no longer wishes to participate in ESADI, it ceases to
participate in ESADI by (1) clearing the ESADI participation bit in
the appropriate Interested VLANs or Interested Lables sub-TLV and (2)
sending a final ESADI-LSP nulling out its ESADI-LSP information.
5.3 Duplicate MAC Address
With ESADI, it is possible to persistently see two occurances of the
same MAC address with the same Data Label being advertised by two or
more RBridges. The specification of how to handle this situation in
[RFC6325] is updated by replacing the last sentence of the last
paragraph of Section 4.2 of [RFC6325] as shown below to provide
better traffic spreading while avoiding possible address flip-
flopping.
H. Zhai, et al [Page 17]
INTERNET-DRAFT TRILL: ESADI
As background, assume some end station or set of end stations have
two or more ports with the same MAC&VLAN with each port connected to
different RBridges (RB1, RB2, ...) by separate links. With ESADI,
some other RBridge, RB0, can persistently see that MAC&VLAN connected
to multiple RBridges. When RB0 ingresses a frame destined that
MAC&VLAN, the current [RFC6325] text permits a wide range of
behavior. In particular, it would permit RB0 to use some rule such as
always send to the egress with the lowest System ID, which would put
all of this traffic through one of the egress RBridges and one of the
end station ports. There would be no load spreading even if there
were multiple different ingress RBridges and/or different MAC
addresses. It also would also permit RB0 to send different traffic to
different egresses by doing ECMP at a flow level, which would likely
result in return traffic to RB0 from RB1, RB2, ... for the same
MAC&VLAN. The resulting address flip-flopping could cause problems.
This update to [RFC6325] avoids these potential difficulties by
requiring RB0 to either (1) use only one egress for a particular
MAC&VLAN but to select that egress pseudo-randomly based on the
topology including MAC reachabilty or (2) if it will not be disturbed
by the returning TRILL Data packets showing the same MAC&VLAN flip-
flopping between different ingresses, it may use ECMP. Assuming
multiple ingress RBridges and/or multiple MAC addresses, stragegy 1
should result in load spreading without address flip-floping while
stragegy 2 will produce more uniform load spreading.
OLD [RFC6325] text:
"... If confidences are also tied between the duplicates, for
consistency it is suggested that RB2 direct all such frames (or
all such frames in the same ECMP flow) toward the same egress
RBridge; however, the use of other policies will not cause a
network problem since transit RBridges do not examine the
Inner.MacDA for known unicast frames."
NEW [RFC6325] text:
"...
If confidences are also tied between the duplicates then RB2 MUST
adopt one of the following two strategies:
1. In a pseudo-random way [RFC4086], select one of the egress
RBridges that is least cost from RB2 and to which the
destination MAC appears to be attached and send all traffic for
the destination MAC and VLAN (or FGL) to that egress. This
pseudo-random choice need only be changed when there is a
change in campus topology or MAC attachment information. Such
pseudo-random selection will, over a population of ingress
RBridges, probabilisticly spread traffic over the possible
egress RBridges. Reasonable inputs to the pseudo-random
selection are the ingress RBridge System ID and/or nickname,
the VLAN or FGL, the destination MAC address, and a vector of
H. Zhai, et al [Page 18]
INTERNET-DRAFT TRILL: ESADI
the RBridges with connectivity to that MAC and VLAN. There is
no need for different RBridges to use the same pseudo-random
function.
2. If RB2 supports ECMP and will not be disturbed by return
traffic from the same MAC and VLAN (or FGL) coming from
different ingress RBridges, then it MAY send traffic over ECMP
at the flow level to the egress RBridges that are least cost
from RB2 and to which the destination MAC appears to be
attached."
H. Zhai, et al [Page 19]
INTERNET-DRAFT TRILL: ESADI
6. ESADI-LSP Contents
The only PDUs used in ESADI are the Level 1 ESADI-LSP, ESADI-CSNP,
and ESADI-PSNP PDUs. Currently, the contents of an ESADI-LSP consists
of zero or more MAC Reachability TLVs, optionally an Authentication
TLV, and exactly one ESADI parameter APPsub-TLV. Other data may be
included in the future and, as in IS-IS, an ESADI instances ignores
any TLVs or sub-TLVs it does not understand.
This section specifies the format for the ESADI parameter data
APPsub-TLV, gives the reference for the ESADI MAC Reachability TLV,
and discusses default authentication configuration.
For robustness, the payload for an ESADI-LSP number zero MUST NOT
exceed 1470 minus 24 bytes in length (1446 bytes) if it has an
Inner.VLAN or 1470 minus 28 bytes (1442 bytes) if it has an
Inner.FGL. But if an ESADI-LSP number zero is received longer, it is
still processed normally.
6.1 ESADI Parameter Data
The figure below presents the format of the ESADI parameter data.
This APPsub-TLV MUST be included in a TRILL GENINFO TLV in ESADI-LSP
number zero. If it is missing from ESADI-LSP number zero or if ESADI-
LSP number zero is not known, priority for the sending RBridge
defaults to 0x40 and CSNP Time defaults to 30. If there is more than
one occurrence in ESADI-LSP number zero, the first occurrence will be
used. Occurrences of the ESADI parameter data APPsub-TLV in non-zero
ESADI-LSP fragments are ignored.
+-+-+-+-+-+-+-+-+
| Type | (1 byte)
+-+-+-+-+-+-+-+-+
| Length | (1 byte)
+-+-+-+-+-+-+-+-+
|R| Priority | (1 byte)
+-+-+-+-+-+-+-+-+
| CSNP Time | (1 byte)
+-+-+-+-+-+-+-+-+
| Flags | (1 byte)
+---------------+
| Reserved for expansion (variable)
+-+-+-+-...
Figure 4. ESADI Parameter APPsub-TLV
Type: set to ESADI-PARAM subTLV (TRILL APPsub-TLV type 1).
H. Zhai, et al [Page 20]
INTERNET-DRAFT TRILL: ESADI
Length: Set to 2 to 255.
R: A reserved bit that MUST be sent as zero and ignored on receipt.
Priority: The Priority field gives the originating RBridge's priority
for being DRB on the ESADI instance virtual link (see Section 2.1)
for the Data Label in which the PDU containing the parameter data
was sent. It is an unsigned seven-bit integer with larger
magnitude indication higher priority. It defaults to 0x40 for an
RBridge participating in ESADI for which it has not been
configured.
CSNP Time: An unsigned byte that gives the amount of time in seconds
during which the originating RBridge, if it is DRB on the ESADI
virtual link, will send at least three EASDI-CSNP PDUs. It
defaults to 30 seconds for an RBridge participating in ESADI for
which it has not been configured.
Flags: A byte of flags associated with the originating ESADI instance
as follows:
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| UN| Reserved |
+---+---+---+---+---+---+---+---+
The UN flag indicates that the RBridge originating the ESADI-
LSP including this ESADI Parameter Data will accept and
properly process ESADI PDUs sent by TRILL unicast. The
remaining bits are reserved for future use and MUST be sent as
zero and ignored on receipt.
Reserved for future expansion: Future versions of the ESADI
Parameters APPsub-TLV may have additional information. A receiving
ESADI RBridge ignores any additional data here unless it
implements such future expansion(s).
6.2 MAC Reachability TLV
The primary information in TRILL ESADI-LSP PDUs consists of MAC
Reachability (MAC-RI) TLVs as specified in [RFC6165]. These TLVs
contain one or more unicast MAC addresses of end stations that are
both on a port and in a VLAN for which the originating RBridge is
appointed forwarder, along with the one octet unsigned Confidence in
this information with a value in the range 0-254. If such a TLV is
received with a confidence of 255, it is treated as if the confidence
was 254. (This is to assure that any received address information can
H. Zhai, et al [Page 21]
INTERNET-DRAFT TRILL: ESADI
be overridden by local address information statically configured with
a Confidence of 255.)
The TLVs in TRILL ESADI PDUs, including the MAC-RI TLV, MUST NOT
contain the Data Label ID. If a Data Label ID is present in the MAC-
RI TLV, it is ignored. In the encapsulated TRILL ESADI packet, only
the Inner.VLAN or Inner.FGL tag indicates the Data Label to which the
ESADI-LSP applies.
6.3 Default Authentication
The Authentication TLV may be included in ESADI PDUs. The default for
ESADI PDU Authentication is based on the state of TRILL IS-IS shared
secret authentication for LSP PDUs. If TRILL IS-IS authentication and
ESADI are implemented at a TRILL switch, then ESADI MUST be able to
use the authentication algorithms implemented for TRILL IS-IS and
implement the keying material derivation function given below. If
ESADI authentication has been configured, that configuration is not
restricted by the configuration of TRILL IS-IS security.
If TRILL IS-IS authentication is not in effect for LSP PDUs
originated by a TRILL switch then, by default, ESADI PDUs originated
by that TRILL switch are also unsecured.
If such IS-IS LSP PDU authentication is in effect at a TRILL switch
then, unless configured otherwise, ESADI PDUs sent by that switch
MUST use the same algorithm in their Authentication TLVs. The ESADI
authentication keying material used is derived from the IS-IS LSP
shared secret keying material as detailed below. However, such
authentication MAY be configured to use some other keying material.
HMAC-SHA256 ( "TRILL ESADI", IS-IS-LSP-shared-key )
In the above HMAC-SHA256 is as described in [FIPS180] [RFC6234] and
"TRILL ESADI" is the eleven byte US ASCII [ASCII] string indicated.
IS-IS-LSP-shared-key is secret keying material being used by the
originating TRILL switch for IS-IS LSP authentication.
H. Zhai, et al [Page 22]
INTERNET-DRAFT TRILL: ESADI
7. IANA Considerations
IANA allocation and registry considerations are given below.
7.1 ESADI Participation and Capability Flags
IANA is requested to allocate bit TBD [3 recommended] as the "ESADI
Participation" bit in the Interested VLANs sub-TLV and the Interested
Labels sub-TLVs [rfc6326bis]. If The ESADI Participation bit is a
one, it indicates that the originating RBridge is participating in
ESADI for the indicated VLAN(s) or FGL(s). In addition, IANA is
requested to create two sub-registries in the TRILL Parameters
Registry for such bits1 as follows:
Sub-Registry: Interested VLANs Flag Bits
Registration Procedures: IETF Review
Note: These bits appear in the Interested VLANs record within the
Interested VLANs and Spanning Tree Roots Sub-TLV (INT-VLAN).
References: [rfc6326bis], This document
Bit Mnemonic Description Reference
--- -------- ----------- ---------
0 M4 IPv4 Multicast Router Attached [rfc6326bis]
1 M6 IPv6 Multicast Router Attached [rfc6326bis]
2 - available for allocation
3 ES ESADI Participation This document
4-15 - (used for a VLAN ID) [rfc6326bis]
16-19 - available for allocation
20-31 - (used for a VLAN ID) [rfc6326bis]
H. Zhai, et al [Page 23]
INTERNET-DRAFT TRILL: ESADI
Sub-Registry: Interested Labels Flag Bits
Registration Procedures: IETF Review
Note: These bits appear in the Interested Labels record within the
Interested Labels and Spanning Tree Roots Sub-TLV (INT-LABEL).
References: [rfc6326bis], This document
Bit Mnemonic Description Reference
--- -------- ----------- ---------
0 M4 IPv4 Multicast Router Attached [rfc6326bis]
1 M6 IPv6 Multicast Router Attached [rfc6326bis]
2 BM Bit Map [rfc6326bis]
3 ES ESADI Participation This document
4-7 - available for allocation
7.2 TRILL GENINFO TLV
IANA is requested to allocate an IS-IS Application Identifier under
the Generic Information TLV (#251) for TRILL [RFC6823] and to create
a subregistry in the TRILL Parameters Registry for "TRILL APPsub-TLVs
under IS-IS TLV #251 Application Identifier #TBD". The initial
contents of this subregistry are as follows:
Type Name Reference
------ -------- -----------
0 Reserved <this RFC>
1 ESADI-PARAM <this RFC>
2-254 Available <this RFC>
255 Reserved <this RFC>
TRILL APPsub-TLV Types 2 through 254 are available for allocation by
IETF Review. The RFC causing such an allocation will also include a
discussion of security issues and of the rate of change of the
information being advertised. TRILL APPsub-TLVs MUST NOT alter basic
IS-IS protocol operation including the establishment of TRILL IS-IS
adjacencies, the IS-IS update process, and the decision process for
TRILL IS-IS [IS-IS] [RFC1195] [RFC6327]. The TRILL Generic
Information TLV MUST NOT be used in an IS-IS instance zero [RFC6822].
The V, I, D, and S flags in the initial flags byte of a TRILL Generic
Information TLV have the meanings specified in [RFC6823] but are not
currently used as TRILL operates as a Level 1 IS-IS area and no
semantics is hereby assigned to the inclusion of an IPv4 and/or IPv6
address via the I and V flags. Thus these flags MUST be zero;
however, use of multi-level IS-IS is an obvious extension for TRILL
H. Zhai, et al [Page 24]
INTERNET-DRAFT TRILL: ESADI
[MultiLevel] and future IETF Standards Actions may update or obsolete
this specification to provide for the use of any or all of these
flags in the TRILL GENINFO TLV.
The ESADI Parameters information, for which TRILL APPsub-TLV 1 is
hereby assigned, is compact and slow changing (see Section 6.1).
For Security Considerations related to ESADI and the ESADI parameters
APPsub-TLV, see Section 8.
H. Zhai, et al [Page 25]
INTERNET-DRAFT TRILL: ESADI
8. Security Considerations
For general TRILL Security Considerations, see [RFC6325].
More TBD
H. Zhai, et al [Page 26]
INTERNET-DRAFT TRILL: ESADI
Normative references
[ASCII] - American National Standards Institute (formerly United
States of America Standards Institute), "USA Code for
Information Interchange", ANSI X3.4-1968, 1968. ANSI X3.4-1968
has been replaced by newer versions with slight modifications,
but the 1968 version remains definitive for the Internet.
[FIPS180] - "Secure Hash Standard (SHS)", United States of American,
National Institute of Science and Technology, Federal
Information Processing Standard (FIPS) 180-4, March 2012,
http://csrc.nist.gov/publications/fips/fips180-4/fips-180-4.pdf
[IS-IS] - International Organization for Standardization,
"Intermediate system to Intermediate system intra-domain
routeing information exchange protocol for use in conjunction
with the protocol for providing the connectionless-mode Network
Service (ISO 8473)", ISO/IEC 10589:2002, Second Edition, Nov
2002.
[RFC1195] - Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
dual environments", RFC 1195, December 1990.
[RFC2119] - Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4086] - Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", BCP 106, RFC 4086, June
2005.
[RFC6165] - Banerjee, A. and D. Ward, "Extensions to IS-IS for
Layer-2 Systems", RFC 6165, April 2011.
[RFC6325] - Perlman, R., Eastlake 3rd, D., Dutt, D., Gai, S., and A.
Ghanwani, "Routing Bridges (RBridges): Base Protocol
Specification", RFC 6325, July 2011.
[RFC6327] - Eastlake 3rd, D., Perlman, R., Ghanwani, A., Dutt, D.,
and V. Manral, "Routing Bridges (RBridges): Adjacency", RFC
6327, July 2011.
[RFC6361] - Carlson, J. and D. Eastlake 3rd, "PPP Transparent
Interconnection of Lots of Links (TRILL) Protocol Control
Protocol", RFC 6361, August 2011.
[RFC6823] - Ginsberg, L., Previdi, S., and M. Shand, "Advertising
Generic Information in IS-IS", RFC 6823, December 2012.
[ClearCorrect] - Eastlake, D., Zhang, M., Ghanwani, A., Manral, V.,
A. Benerjee, "TRILL: Clarifications, Corrections, and Updates",
H. Zhai, et al [Page 27]
INTERNET-DRAFT TRILL: ESADI
draft-ietf-trill-clear-correct, in RFC Editor's queue.
[rfc6326bis] - Eastlake, D., Senevirathne, T., Ghanwani, A., Dutt,
D., and A. Banerjee, "Transparent Interconnection of Lots of
Links (TRILL) Use of IS-IS", draft-ietf-isis-rfc6326bis, work
in progress.
[RFCfgl] - Eastlake, D., M. Zhang, P. Agarwal, R. Perlman, D. Dutt,
"TRILL (Transparent Interconnection of Lots of Links): Fine-
Grained Labeling", draft-ietf-trill-fine-labeling, work in
progress.
Informative References
[802.1X] - IEEE 802.1, "IEEE Standard for Local and metropolitan area
networks / Port-Based Network Access Control", IEEE Std
802.1X-2010, 5 February 2010.
[RFC6822] - Previdi, S., Ed., Ginsberg, L., Shand, M., Roy, A., and
D. Ward, "IS-IS Multi-Instance", RFC 6822, December 2012.
[MultiLevel] - Perlman, R., D. Eastlake, A. Ghanwani, H. Zhai,
"Multilevel TRILL (Transparent Interconnection of Lots of
Links)", draft-perlman-trill-rbridge-multilevel, work in
progress.
[RFC3748] - Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
Levkowetz, Ed., "Extensible Authentication Protocol (EAP)", RFC
3748, June 2004.
[RFC6234] - Eastlake 3rd, D. and T. Hansen, "US Secure Hash
Algorithms (SHA and SHA-based HMAC and HKDF)", RFC 6234, May
2011.
[VLANmapping] - Perlman, R., D. Dutt, A. Banerjee, A. Rijhsinghani,
and D. Eastlake, "RBridges: Campus VLAN and Priority Regions",
draft-ietf-trill-rbridge-vlan-mapping, work in progress.
H. Zhai, et al [Page 28]
INTERNET-DRAFT TRILL: ESADI
Appendix Z: Change History
RFC Editor: Please delete this section before publication.
Z.1 From -00 to -01
1. Add Section 6.3 "Default Authentication".
2. Add "Acknowledgements" Section.
3. Change requirement from "MAY" to "SHOULD" for an ESADI RBridge
that is not DRB to send an ESADI-CSNP if it does not receive an
ESADI-CSNP in long enough.
4. Default CSNP Time was listed as 30 in one place and 40 in another.
Change to uniformly specify 30.
5. Update references to RFC 6326 to reference the 6326bis draft.
6. Relax allocation criteria for TRILL APPsub-TLV type code points
from Standard Action to IETF Review.
7. Numerous Editorial changes.
Z.2 From -01 to -02
1. Extend to cover FGL and well as VLAN and introduce the term "Data
Label" to cover both.
2. Expand number of LSP fragments to 2**16.
3. Simplify neighbor detection to no longer require possesion of
ESADO LSP zero.
4. Add update to last sentence of Section 4.2 of [RFC6325].
5. Update references for publication of RFCs 6822 and 6823.
6. Additional minor changes.
H. Zhai, et al [Page 29]
INTERNET-DRAFT TRILL: ESADI
Authors' Addresses
Hongjun Zhai
ZTE Corporation
68 Zijinghua Road
Nanjing 200012 China
Phone: +86-25-52877345
Email: zhai.hongjun@zte.com.cn
Fangwei Hu
ZTE Corporation
889 Bibo Road
Shanghai 201203 China
Phone: +86-21-68896273
Email: hu.fangwei@zte.com.cn
Radia Perlman
Intel Labs
2200 Mission College Blvd.
Santa Clara, CA 95054-1549 USA
Phone: +1-408-765-8080
Email: Radia@alum.mit.edu
Donald Eastlake
Huawei R&D USA
155 Beaver Street
Milford, MA 01757 USA
Phone: +1-508-333-2270
Email: d3e3e3@gmail.com
Olen Stokes
Extreme Networks
Pamlico Building One, Suite 100
3306 East NC Hwy 54
RTP, NC 27709 USA
Email: ostokes@extremenetworks.com
H. Zhai, et al [Page 30]
INTERNET-DRAFT TRILL: ESADI
Copyright and IPR Provisions
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. The definitive version of
an IETF Document is that published by, or under the auspices of, the
IETF. Versions of IETF Documents that are published by third parties,
including those that are translated into other languages, should not
be considered to be definitive versions of IETF Documents. The
definitive version of these Legal Provisions is that published by, or
under the auspices of, the IETF. Versions of these Legal Provisions
that are published by third parties, including those that are
translated into other languages, should not be considered to be
definitive versions of these Legal Provisions. For the avoidance of
doubt, each Contributor to the IETF Standards Process licenses each
Contribution that he or she makes as part of the IETF Standards
Process to the IETF Trust pursuant to the provisions of RFC 5378. No
language to the contrary, or terms, conditions or rights that differ
from or are inconsistent with the rights and licenses granted under
RFC 5378, shall have any effect and shall be null and void, whether
published or posted by such Contributor, or included with or in such
Contribution.
H. Zhai, et al [Page 31]