TRILL Working Group Hongjun Zhai
INTERNET-DRAFT Fangwei Hu
Intended status: Proposed Standard ZTE
Updates: RFCtrill Radia Perlman
Intel Labs
Donald Eastlake
Huawei
Expires: January 2, 2012 July 3, 2011
RBridges: The ESADI Protocol
<draft-hu-trill-rbridge-esadi-00.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
safe forwarding even during periods of temporary loops. TRILL
supports VLANs and the multi-pathing of both unicast and multicast
traffic. TRILL accomplishes this by using IS-IS (Intermediate System
to Intermediate System) link state routing and encapsulating traffic
using a header that includes a hop count. Devices that implement
TRILL are called RBridges (Routing Bridges).
The ESADI (End System Address Distribution Information) protocol is a
VLAN (Virtual Local Area Network) scoped way that RBridge can
communicate end station addresses to each other. An RBridge
announcing VLAN-x connectivity (normally a VLAN-x forwarder) and
running the TRILL ESADI protocol receives remote address information
and/or transmits local address information for VLAN-x. The purpose
of this document is to improve the documentation of the ESADI
protocol. The ESADI RBridge instance states, DRB (Designated
RBridge) election procedure, and ESADI sub-TLVs are specified in this
document.
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 RBridges: 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
Acknowledgements
TBD
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Table of Contents
1. Introduction............................................4
1.1 Content and Precedence.................................5
1.2 Terminology............................................5
2. ESADI Protocol Overview.................................6
3. ESADI DRB Election......................................8
3.1 ESADI DRB..............................................8
3.2 ESADI RBridge Instance States..........................8
3.3 ESADI DRB election events..............................9
3.4 Timers.................................................9
3.5 ESADI Neighbor List...................................10
3.6 State Table and Diagram...............................10
4. ESADI PDU processing...................................13
4.1 Sending of ESASI PDUs.................................13
4.2 Receipt of PDUs.......................................14
5. ESADI LSP Contents.....................................16
5.1 ESADI Participation Data..............................16
5.2 ESADI MAC Address sub-TLV.............................17
6. IANA Considerations....................................18
7. Security Considerations................................18
8. References.............................................19
8.1 Normative references..................................19
8.2 Informative References................................19
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1. Introduction
The IETF TRILL (TRansparent Interconnection of Lots of Links)
protocol [RFCtrill] provides least cost pair-wise data forwarding
without configuration in multi-hop networks with arbitrary
topologies, safe forwarding even during periods of temporary loops,
and support for multi-pathing of both unicast and multicast traffic.
TRILL accomplishes this by using IS-IS (Intermediate System to
Intermediate System) [IS-IS] [RFC1195] [TRILLisis] link state routing
and encapsulating traffic using a header that includes a hop count.
The design supports VLANs (Virtual Local Area Networks) and
optimization of the distribution of multi-destination frames based on
VLANs and IP derived multicast groups. Devices that implement TRILL
are called RBridges (Routing Bridges).
There are five ways an RBridge can learn end station addresses as
described in Section 4.8 of [RFCtrill]. The ESADI (End Station
Address Distribution Information) protocol is an optional VLAN scoped
way RBridges can communicate end station addresses with each other.
An RBridge that is announcing connectivity to VLAN-x (normally a
VLAN-x appointed forwarder) MAY use the (ESADI) protocol to announce
some or all of its attached VLAN-x end nodes.
By default, RBridges with connected end stations learn addresses from
the data plane when ingressing and egressing native frames. The ESADI
protocols potential advantages over data plane learning include the
following:
1. Security advantages: The EDADI protocol can be used to announce
end stations with an authenticated enrollment (for example
enrollment authenticated by cryptographically based EAP
(Extensible Authentication Protocol) methods via [802.1X]). In
addition, the ESADI protocol supports cryptographic authentication
of its message payloads for more secure transmission.
2. Fast update advantages: ESADI protocol provides a fast update of
end nodes MAC (Media Access Control) addresses. If an end station
is unplugged from one RBridge and plugged into another one, frames
addressed to that older RBridge can be black holed. They can be
sent just to the older RBridge that the end station was connected
to until cached address information at some remote RBridge times
out, possibly for tens of seconds [RFCtrill].
MAC address reachability information and some ESADI parameters are
carried in ESADI frames rather than in the core TRILL IS-IS protocol.
As described below, ESADI is, for each VLAN, a virtual logical
topology overlay in the TRILL topology. An advantage of using ESADI
is that the end station attachment information is not flooded to all
RBridges through the core IS-IS instance but only to participating
RBridges advertising attachment to the VLAN in which those end
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stations occur.
1.1 Content and Precedence
This document supplements and enriches the description of the ESADI
protocol in the TRILL basic specification, especially the ESADI DRB
(Designated RBridge) election procedure, ESADI instance state
specification, and ESADI parameter announcement. Section 2 is the
ESADI protocol overviews. Section 3 specifics ESADI DRB principles,
ESADI instance state and DRB election. Section 4 discusses the
processing of EASDI PDUs. Section 5 describes two ESADI sub-TLVs: one
with ESADI participation information and the MAC Address sub-TLV.
This document updates [RFCtrill] and prevails over [RFCtrill] in the
case of conflicts.
1.2 Terminology
This document uses the acronyms defined in [RFCtrill].
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].
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2. ESADI Protocol Overview
ESADI is a VLAN scoped way that RBridges can announce and learn end
station addresses rapidly and securely. An RBridge that is
announcing itself as connected to one or more VLANs (usually because
it is an Appointed Forwarder) and participates in the ESADI protocol
is called an ESADI RBridge.
ESADI is a separate protocol from the core IS-IS instance implemented
by all RBridges in a campus. There is a separate ESADI instance for
each VLAN. In essence, for each VLAN, there is an instance of the IS-
IS reliable flooding mechanism in which ESADI RBridges may choose to
participate. (These are not the instances being specified in [draft-
mi].) It is an implementation decision how independent the
implementtion of multiple ESADI instances at an RBridge are. For
example, the ESADI link state could be in a single database with a
field in each record indicating the VLAN to which it applies.
After the TRILL header, ESADI frames have an inner Ethernet header
with the Inner.MacDA of "All-Egress-RBridges" (formerly called "All-
ESADI-RBridges"), an Inner.VLAN tag specifying the VLAN of interest,
and the "L2-IS-IS" Ethertype followed by the ESADI payload as shown
in Figure 1. For more detail see Section 4.2.5 in the TRILL base
protocol specification [RFCtrill].
TRILL ESADI frame Structure
+--------------------------------+
| Link Header |
+--------------------------------+
| TRILL Data Header |
+--------------------------------+
| Inner Ethernet Header |
+--------------------------------+
| ESADI Payload |
+--------------------------------+
| Link Trailer |
+--------------------------------+
Figure 1
All transit RBridges forward ESADI frames as if they were ordinary
multicast TRILL Data frames. Because of this forwarding, it appears
to 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 VLAN. Thus no "routing" computation or
decisions ever have to be made by ESADI. A participating RBridge
merely transmits the ESADI frames it originates on this virtual link
by multicasting it as described in [RFCtrill]. RBridges that do not
implement the ESADI protocol, do not have it enabled, or are not
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announcing connectivity for the Inner.VLAN of an ESADI frame do not
decapsulate or locally process any TRILL ESADI frames they receive.
Thus the ESADI frames are transparently tunneled through transit
RBridges.
TRILL ESADI frame payloads are structured like IS-IS frames but are
always TRILL encapsulated on the wire as if they were TRILL Data
frames. The information and adjacency relation between ESADI
RBridges are based on the ESADI frames that are carried as TRILL
multicast data frames
The ESADI instance for VLAN X at an RBridge acquires a neighbor when
it first receives ESADI-LSP fragment zero from that neighbor and that
neighbor is an existing RBridge in the core IS-IS instance link state
database. When the entry for an RBridge is purged from the core IS-IS
link state database, it is also purged from any ESADI instances and
is lost as a neighbor.
The information distributed with the ESADI protocol is a list of
local end station MAC addresses known to the originating RBridge and,
for each such address, a one octet unsigned "confidence" rating in
the range 0-254 (see Section 5.2). It is entirely up to the
originating RBridge which locally connected MAC addresses it wishes
to advertise via ESADI. It MAY advertise all, some, or none of such
addresses it has.
TRILL ESADI LSPs do not contain a VLAN ID in their payload. The VLAN
ID to which the ESADI data applies is the Inner.VLAN of the frame. If
a VLAN ID could occur within the payload, it might conflict with the
Inner.VLAN and could conflict with any future VLAN mapping scheme
that may be adopted [VLAN-Mapping]. If a VLAN ID field in an ESADI
frame payload does include a VLAN ID, its contents is ignored.
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3. ESADI DRB Election
3.1 ESADI DRB
It is necessary to elect one ESADI RBridge DRB from all the ESADI
RBridges for each VLAN where ESADI is being used. The ESADI DRB is
responsible for Link State Database synchronization with other
RBridges by issuing ESADI-CSNP PDUs periodically and responding to
PSNPs on the virtual link.
3.2 ESADI RBridge Instance States
There are four states for each ESADI RBridge instance: Down, Initial,
Not-DRB and DRB. The state descriptions are as following:
Down: This is a virtual state for convenience in creating state
diagrams and tables. It indicates that the ESADI instance is
operationally down.
Initial: This state indicates that an ESADI instance is up but does
not know of any ESADI neighbors (i.e., the only entry in its
neighbor list is itself). Once ESADI enters this state, it
should start the Holding Timer, and multicast self-originated
fragment zero LSPs to other RBridges. If a valid ESADI neighbor
is found by receiving an ESADI LSP, the ESADI instance will
leave this state and enter into "Not-DRB" state. In this state,
the Holding Timer will be reset if the timer is expired or the
found neighbor has a higher priority than the local priority.
Not-DRB: This state indicates that the ESADI instance has found at
least one valid ESADI neighbor and is not DRB yet. If there is
no Holding Timer running, the timer will be started. If an
ESADI LSP or a CSNP PDU is received from a higher priority
ESADI RBridge, the Holding Timer will be reset. If the Holding
Timer expires, the ESADI instance will enter into "DRB" state.
DRB: In this state, the ESADI instance multicasts the ESADI CSNP PDUs
periodically to keep Link State Database synchronization with
its neighbors on virtual link, and responds to ESADI-PSNP PDUs
with ESADI-LSPs. If an EDADI PDU (i.e., LSP, CSNP and PSNP) is
received from a neighbor with a higher priority than its own,
the ESADI instance will move to the "Not-DRB" state.
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3.3 ESADI DRB election events
The following events can change the ESADI state. These are all events
for a particular ESADI VLAN-x instance.
E1 ESADI instance is operationally up;
E2 Finding the first ESADI neighbor;
E3 Holding Timer expired;
E4 Receiving an ESADI PDU from an ESADI neighbor with higher
priority;
E5 Losing the last ESADI neighbor;
E6 ESADI instance goes operationally down;
(Receiving an ESADI PDU from an ESADI neighbor with lower priority
has no effect on the ESADI instance state.)
Priority is determined by the seven-bit priority field in the ESADI
participation data (see Section 5.1), with the System ID as a tie
breaker, both considered as unsigned integers with the larger
quantity indicating higher priority.
3.4 Timers
There are two timers for ESADI DRB election: one the Holding Timer,
the other the Waiting Timer. The Holding Timer is a cyclic timer, and
is used in connection with ESADI-CSNP PDUs. If this timer expires,
the local ESADI instance will start multicasting its own ESADI-CSNP
PDUs and, if it was in the Non-DRB state, it decides that the DRB is
being non-responsive and moves to the DRB state.
The Waiting Timer is a non-cyclic timer. This timer is started by the
change of neighbor's DRB status and killed by its expiration. It is
used to alleviate the PDUs storm stirred by Link State Database
synchronization in the case of current DRB being preempted by a new
ESADI neighbor with higher priority. If this timer expires, the new
DRB is confirmed and its ESADI parameters, such as intervals of
holding timer and waiting timer, are accepted to overwrite the local
parameters.
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3.5 ESADI Neighbor List
In order to be able to access key information about ESADI neighbors
easily, an ESADI neighbor list is maintained for each ESADI VLAN-x
instance. Each entry in this list represents an ESADI neighbor for
VLAN-x.
For each neighbor, there will be a fragment zero LSP from that
neighbor in the ESADI instance link state. A list entry is created
when such a fragment zero LSP is first received on the ESADI virtual
link from some RBridge that exists in the core IS-IS instance link
state database. A neighbor entry for an RBridge is deleted when that
RBridge is purged from the core IS-IS instance link state database.
For each neighbor, the parameters of System-ID/nickname, priority,
holding timer interval, waiting timer interval and the DRB flag, are
stored in its respective entry in this list.
The DRB flag indicates whether a neighbor is regarded as DRB or not.
If this flag is 1, the associated neighbor is considered as DRB,
otherwise, not DRB. At any moment, there is no more than one entry
that is flagged as DRB in this list. The DRB status of a neighbor can
be changed by the receipt of ESADI-CSNP PDUs coupled with the
priorities of the originators of the PDUs, together with the priority
of the local ESADI instance (see Section 4.2 for more details). When
the DRB flag of one entry, such as the entry of the local ESADI
instance, is changed in this list, the Waiting Timer will be started
if it is not running. When the timer is expired, the neighbor, whose
DRB flag is 1, will be confirmed as real DRB, and its CSNP PDUs will
be used to accomplish Link State Database synchronization with other
ESADI RBridges.
If the ESADI instance is in "Initial" state, there is only one entry
existing in this list, where the parameters of the local ESADI VLAN-x
instance is saved. If a new entry is added to this list and the entry
is the second one, an E2 event will occur, which drives the state of
this ESADI instance into "Not-DRB" from "Initial". When there are
only two entries in this list, if the second entry is removed from
this list, an E5 event is originated, which draws this ESADI instance
back to "Initial" state from "Not-DRB" or "DRB".
3.6 State Table and Diagram
The table below shows the transitions between the RBridge ESADI
instance states defined above based on the events defined above:
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TRILL ESADI State Table
| Event | Down | Initial | Not-DRB | DRB |
+-------+---------+---------+---------+---------+
| E1 | Initial | N/A | N/A | N/A |
| E2 | N/A | Not-DRB | N/A | N/A |
| E3 | N/A | Initial | DRB | N/A |
| E4 | N/A | Initial | Not-DRB | Not-DRB |
| E5 | N/A | Initial | Initial | Initial |
| E6 | Down | Down | Down | Down |
+-------+---------+---------+---------+---------+
Figure 2
N/A indicates that the event to the left is Not Applicable in the
state at the top of the column.
The first state is "Down". Once an RBridge ESADI instance is
operationally up, it enters into "Initial" state. An ESADI instance
should start the Holding Timer and multicast its self-originated
fragment zero LSP to other ESADI RBridges. When the first valid ESADI
neighbor is found on the virtual link, the ESADI instance enters
"Not-DRB" state, otherwise the ESADI instance remains in "Initial"
state and resets the Holding Timer whenever the timer expires. And if
the neighbor's priority is higher than its own, the Holding Timer
will be reset before the ESADI instance enters the "Not-DRB" state.
In both the "Non-DRB" and "DRB" states, the ESADI RBridge multicasts
all its self-originated LSP fragments.
In the "Not-DRB" state, if any ESADI PDUs are received from ESADI
neighbors with higher priorities, the Holding Timer will be reset.
Otherwise, if the timer expires without hearing from a higher
priority neighbor, the ESADI instance will enter "DRB" state. An
ESADI DRB can be preempted by a higher priority neighbor. If the DRB
receives an ESADI PDU from a higher priority neighbor, the ESADI
instance will move to "Not-DRB" state. As DRB, an ESADI instance will
multicast ESADI-CSNP PDUs to all neighbors on the virtual link
periodically, and respond to the ESADI-PSNP PDUs with ESADI-LSP PDUs
by multicasting them.
Below is the same information as in the state table presented as a
diagram.
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TRILL ESADI state diagram
+------------------+
| Down |<--------+
+------------------+ |
| ^ | ^ |
|E1 |E5 | E6 | |
V | +-----+ |
+------------------+ E6 |
+---->| Initial |---------|
| +------------------+ |
| | ^ | ^ |
| |E2 |E5 |E3,E4,E5| |
| V | +--------+ |
| +------------------+ E6 |
| | Not-DRB |---------|
| +------------------+ |
| | ^ | ^ |
| |E3 |E4 | E4 | |
| V | +-------+ |
| E5 +------------------+ E6 |
+-----| DRB |---------+
+------------------+
Figure 3
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4. ESADI PDU processing
VLAN-x ESADI neighbors are usually not connected directly by a
physical link, but are always logically connected by a virtual link.
There may be hundreds of ESADI RBridges on the virtual link. There
are only LSP, CSNP and PSNP PDUs used in ESADI. In particular, there
are no Hellos because ESADI does not need to build a topology and
does not need to do any routing.
In IS-IS, multicasting is normally 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 entire link busy for that frame time. But
in ESADI what appears to be a simple multi-access link is actually a
multi-hop distribution tree that may or may not be pruned. Thus,
transmitting a multicast frame on such a tree imposes 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 unicast.
An undesirable storm of LSP PDUs may be sent to update a new ESADI
RBridge when it starts to participate in VLAN-x ESADI if it has
higher priority and becomes DRB on the virtual link.
Section 4.1 describes the sending of ESADI PDUs. Section 4.2 covers
the receipt of ESADI PDUs.
4.1 Sending of ESASI PDUs
When the VLAN-x ESADI instance is in "Not-DRB" or "DRB" state and a
new neighbor is found, its self-originated LSP fragments are
scheduled to be sent and MAY be unicast to that neighbor. The
interval elapsed before sending the LSP(s), depends on the priority
of the local ESADI instance. The higher the priority, the shorter
the interval is.
In the case of receiving an LSP with a smaller sequence number than
the LSP copy stored in local Link State Database, the local ESADI
instance will also schedule to transmit the stored LSP copy and MAY
unicast it to the sender. After the sender receives such a LSP, it
can originate a new LSP, whose sequence number is bigger than the
received sequence number, to refresh the LSP in all the neighbors.
If the ESADI instance is DRB, it multicasts a CSNP periodically to
keep the Link State Database synchronized among its neighbors on the
virtual link. After receiving a PSNP PDU, the DRB will transmit the
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LSPs requested by the PSNP on the virtual link.
If the ESADI instance is not DRB, it will schedule multicasting only
its self-originated LSP on the virtual link when it finds the DRB
losing some LSPs or having stale LSPs, including the local ESADI
instance's self-originated LSPs, from the CSNP PDUs it receives. The
higher the priority, the shorter the interval is.
The format of a unicast ESADI frame is the format of TRILL ESADI
frame, in section 4.2 in [RFCtrill], except that, 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 PDUs
When an ESADI PDU is received, the receiver checks for the
originator's System ID in the receiver's core IS-IS instance link
state database. If the System ID is not present, the PDU is
discarded.
After receiving a new ESADI LSP with a known System ID, the LSP will
be installed into or replaced the older copy of this LSP in the local
ESADI Link State Database. If it is a fragment zero LSP, the local
ESADI instance will try to find the originator of the LSP in its
neighbor list. If the neighbor is found, any different parameters of
this neighbor will be stored in the associated entry in the neighbor
list. Otherwise, a new neighbor is detected, and an associated entry
is inserted into the list to store this neighbor's information. If
the local EASDI instance is in "Initial" state and the entry is the
second entry in the neighbor list, an E2 event will be originated,
which will push this ESADI instance into "Not-DRB" state from
"Initial".
On receiving a CSNP PDU with a known System ID, if the ESADI instance
is in "Initial" state, the PDU is used for Link State Database
synchronization. Otherwise, the local ESADI instance tries to find
the originator in its neighbor list. In the following cases, the CSNP
PDU will be discarded:
1) The originator is not found in the neighbor list;
2) The originator is found in the list, but its priority is not
higher than the local ESADI instance's priority.
If the CSNP PDU is not discarded and the local ESADI instance is in
"Not-DRB" or "DRB" state, it will be used to update the DRB flag in
the entries in the neighbor list, i.e., the originator's DRB flag is
set to 1 and other entries' DRB flag is cleared to zero. The above
update may make the potential DRB change from one neighbor to
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another; if so, the Waiting Timer will be started if it is not
running. If potential DRB doesn't change from one neighbor to
another, and the Waiting Timer is not running yet, this CSNP PDU is
used for Link State Database synchronization. ESADI-PSNP PDUs will be
multicast on the virtual link to request fresh copies of lost or
stale LSPs from DRB, if necessary.
When receiving a PSNP PDU, if the local ESADI instance is DRB and the
Waiting Timer is not running, LSP PDU associated the PSNP will be
multicast on the virtual link. Otherwise, the PSNP PDU is discarded.
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5. ESADI LSP Contents
The only PDUs used in ESADI are the Level 1 LSP, CSNP, and PSNP PDUs.
This section specifies the format for ESADI participation data sub-
TLV and gives the reference for the ESADI MAC Reachability TLV.
5.1 ESADI Participation Data
The figure below presents the format of the ESADI participation data.
This sub-TLV MUST be included in LSP fragment zero. LSP fragment zero
MUST NOT exceed 1470 bytes in length.
[[ This should probably be a Router Capabilities TLV and this section
probably needs to be in an ISIS WG draft. ]]
Participation Data
+-+-+-+-+-+-+-+-+
| Type | (1 byte)
+-+-+-+-+-+-+-+-+
| Length | (1 byte)
+-+-+-+-+-+-+-+-+
|D| Priority | (1 byte)
+-+-+-+-+-+-+-+-+
| Holding Time | (1 byte)
+-+-+-+-+-+-+-+-+
| Waiting Time | (1 byte)
+-+-+-+-+-+-+-+-+
Figure 4
Type: set to TBD
Length: Set to 3.
D: If the sub-TLV is originated by the DRB or an EASDI instance
sending CSNPs as DRB, the D field is set to 1, otherwise, the
field is zero.
Priority: The Priority field gives the RBridge's priority for being
DRB on the TRILL EASDI virtual link for the VLAN in which the PDU
containing the Participation data was sent. It is a 7-bit unsigned
integer.
Holding Time: Gives the holding time in seconds as an unsigned
integer.
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Waiting Time: Gives the waiting time in seconds as an unsigned
integer.
When an ESADI instance receives a participation data sub-TLV in which
the D field is set to 1 and the originator of this LSP is confirmed
DRB by the local ESADI instance as highest priority, the RBridge sets
the local Holding Timer according to the value of holding time field,
and sets the local Waiting Timer according to the value of waiting
time field.
5.2 ESADI MAC Address sub-TLV
The information in TRILL ESADI LSP PDUs consists of one or more 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.
To avoid conflict with the Inner.VLAN ID, the TLVs in TRILL EASDI
PDUs, including the MAC-RI TLV, MUST NOT containing the VLAN ID. If a
VLAN-ID is present in the MAC-RI TLV, it is ignored. The VLAN to
which the ESADI-LSP applies is indicated only by the Inner.VLAN tag
in the encapsulated TRILL ESADI frame.
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6. IANA Considerations
TBD
7. Security Considerations
TBD
For general TRILL Security Considerations, see [RFCtrill].
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8. References
Normative and informative references for this document are below.
8.1 Normative references
[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.
[RFC4971] - Vasseur, JP., N. Shen, and R. Aggarwal, "Intermediate
System to Intermediate System (IS-IS) Extensions for
Advertising Router Information", RFC 4971, July 2007.
[RFC6165] - Banerjee, A. and D. Ward, "Extensions to IS-IS for
Layer-2 Systems", RFC 6165, April 2011.
[TRILLisis] - Eastlake, D., A. Banerjee, D. Dutt, R. Perlman, A.
Ghanwani, "TRILL Use of IS-IS", draft-ietf-isis-trill-05, in
RFC Editor's queue.
[RFCtrill] - Perlman, R., Eastlake, D., Dutt, D., Gai, S., and A.
Ghanwani, "RBridges: Base Protocol Specification", draft-ietf-
trill-rbridge-protocol-16.txt, in RFC Editor's queue, Mar 2010.
8.2 Informative References
[802.1X] - IEEE 802.1, "IEEE Standard for Local and metropolitan area
networks / Port-Based Network Access Control", IEEE Std
802.1X-2004, 13 December 2004.
[VLAN-Mapping] - Perlman, R., D. Dutt, A. Banerjee, A. Rijhsinghani,
and D. Eastlake, "RBridges: Campus VLAN and Priority Regions",
draft-ietf-trill-rbridge-vlan-mapping-05.txt, work in process,
April 2011.
H. Zhai, et al [Page 19]
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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 Technologies
155 Beaver Street
Milford, MA 01757 USA
Phone: +1-508-333-2270
Email: d3e3e3@gmail.com
H. Zhai, et al [Page 20]
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Copyright and IPR Provisions
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This document is subject to BCP 78 and the IETF Trust's Legal
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include Simplified BSD License text as described in Section 4.e of
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Contribution.
H. Zhai, et al [Page 21]
