RBridges: TRILL Link Data Optimizations
draft-perlman-trill-rbridge-data-encoding-02
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Radia Perlman , Donald E. Eastlake 3rd , Yizhou Li , Anoop Ghanwani | ||
| Last updated | 2012-07-13 | ||
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draft-perlman-trill-rbridge-data-encoding-02
TRILL Working Group Radia Perlman
INTERNET-DRAFT Intel Labs
Updates: 6325 Donald Eastlake
Intended status: Proposed Standard Yizhou Li
Huawei
Anoop Ghanwani
Dell
Expires: January 12, 2013 July 13, 2012
RBridges: TRILL Link Data Optimizations
<draft-perlman-trill-rbridge-data-encoding-02.txt>
Abstract
TRILL (TRansparent Interconnection of Lots of Links) Data frames can
be encoded so as to make more efficient use of communications links
under certain circumstances. This document specifies two such
optional optimizations. One, called Compact Format, improves the
compactness of encoding where a TRILL link is a point-to-point
Ethernet link. The other, called Specific Addressing, optionally
decreases the burden on multi-access TRILL links for multi-
destination TRILL Data frames. This document updates RFC 6325.
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.
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.
R. Perlman, et al [Page 1]
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Table of Contents
1. Introduction............................................3
1.1 Structure of This Document.............................3
1.2 Terminology Used in This Document......................4
2. The General TRILL Frame Format..........................5
2.1 The General TRILL Frame Format.........................5
2.2 Ethernet Link TRILL Data Frame General Encapsulation...6
3. Compact Format for Point-to-Point Ethernet Links........8
3.1 Conditions for Using Compact Format....................8
3.2 RBridge Originated and Terminated Native Frames.......10
3.3 Compact TRILL Data Reception and Transmission.........10
3.3.1 Compact TRILL Data Frame Reception..................10
3.3.2 Compact TRILL Data Frame Transmission...............12
3.4 Announcing Support for Compact Format.................12
4. Specific Addressing....................................13
4.1 Current Multi-Destination Addressing..................13
4.2 Specific Addressing Specification.....................13
4.3 Announcing Support for Specific Addressing............13
5. Interaction Between The Optimizations..................15
6. IANA Considerations....................................16
7. Security Considerations................................17
7.1 Compact Format Security Considerations................17
7.2 Specific Addressing Security Considerations...........17
7.3 Results of Frame Misinterpretation....................17
8. References.............................................19
8.1 Normative References..................................19
8.2 Informative References................................19
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1. Introduction
RBridges (Routing Bridges) are devices that support the IETF TRILL
(TRansparent Interconnection of Lots of Links) protocol [RFC6325]
[RFC6327] [ClearCorrect]. They provide transparent forwarding of
frames in multi-hop networks with arbitrary topology and link
technology using least cost paths for unicast traffic and support
VLANs (Virtual Local Area Networks) and the multipathing of both
unicast and multi-destination traffic. They accomplish this by use of
encapsulation with a hop count and IS-IS (Intermediate System to
Intermediate System) link state routing [IS-IS] [RFC1195]
[RFC6326bis].
A link between two RBridges in an RBridge campus can be any of a
variety of technologies, ranging from a complex bridged LAN to PPP
[RFC6361]. In the general case under the current TRILL standard, a
TRILL Data frame consists of an inner payload formatted as an
Ethernet frame, preceded by a TRILL Header, and then encapsulated by
a link envelope as appropriate for the link technology.
1.1 Structure of This Document
Section 2 discusses General Format TRILL Data frames without the
enhancements specified in this document.
In the case where the link is a point-to-point Ethernet link, an
optional Compact Format is possible for TRILL Data frames that saves
16 bytes. Section 3 specifies that format, its processing, and the
conditions for its safe use.
In the case where a multi-destination TRILL Data frame is being
forwarded over a multi-access link with multiple ports connected but
there is only one (or perhaps a few) next hop RBridges of interest,
optional Specific Addressing allows the TRILL Data frame to be link
unicast. This can substantially reduce the burden that frame
represents if, for example, the link is a complex bridged LAN through
which the frame might otherwise be flooded. Section 4 specifies the
Specific Addressing enhancement and the conditions for its safe use.
Section 5 discusses potential interaction between these two
enhancements. The remaining Sections after Section 5 provide IANA and
Security Considerations, References, and the like.
This document updates [RFC6325].
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1.2 Terminology Used in This Document
The terminology and acronyms defined in [RFC6325] are used herein
with the same meaning. In particular, the terms "campus", "native
frame", "link", etc., are as defined [RFC6325].
"Point-to-point", as used herein, means a link which appears to be an
isolated channel between exactly two RBridge ports. Such a link may
not include customer bridges but may include hubs/repeaters, Two Port
MAC Relays, Provider Bridges, Provider Back Bone Bridges [802.1Q], or
other technology, provided that technology is configured to provide a
transparent point-to-point path between the end point RBridge ports.
References herein to "VLAN Tag" or the like are to customer VLANs (C-
Tags, Ethertype 0x8100). Use of S-Tags, also known as Service Tags,
or stacked VLAN or other tags is beyond the scope of this document
but is an obvious extension.
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. The General TRILL Frame Format
The subsections below provide a description of the general format of
TRILL Data frames. It then narrows in to describe the format of TRILL
Data frames on Ethernet links.
2.1 The General TRILL Frame Format
The general "on-the-wire" form of TRILL frames is illustrated below.
The Link Headers and Trailers in the formats below depend on the
specific link technology. The Link Header contains one or more fields
that distinguish TRILL Data from TRILL IS-IS. For example, over
Ethernet, the TRILL Data Link Header ends with the TRILL Ethertype
while the TRILL IS-IS frame Link Header ends with the L2-IS-IS
Ethertype; on the other hand, over PPP, there are no Ethertypes but
PPP protocol codes perform that function [RFC6361].
A TRILL Data frame in transit between two neighboring RBridges is as
shown below:
+---------------+----------+----------------+---------------+
| TRILL Data | TRILL | Payload | TRILL Data |
| Link Header | Header | Native Frame | Link Trailer |
+---------------+----------+----------------+---------------+
Figure 1. Format of TRILL Data Frames
In the above diagram, the Payload Native Frame is in a restricted
Ethernet frame format with a VLAN tag but with no trailing Frame
Check Sequence (FCS). The payload frame format is shown below,
assuming the payload starts with an Ethertype (it might alternatively
be LLC [802-2001] encoded or some other format):
+-----------+------------+------+-----------+------------
| MAC Dest. | MAC Source | VLAN | Content | Content ...
| Address | Address | Tag | Ethertype | ...
+-----------+------------+------+-----------+------------
Figure 2. Format of the Payload Native Frame
The encapsulated payload has the following fields in sequence:
o A 6-byte destination MAC address (Inner.MacDA)
o A 6-byte source MAC address (Inner.MacSA)
o An Inner.VLAN tag giving the VLAN ID, Priority, and DEI (Drop
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Eligibility Indicator) [ClearCorrect] of the payload (use of an S-
tag or stacked tags is beyond the scope of this document but is an
obvious extension)
o The payload frame's content (which usually starts with an
Ethertype, such as the Ethertype for IPv4 or IPv6)
TRILL IS-IS frames are also sent between neighboring RBridges and
must be distinguished from TRILL Data frames. TRILL IS-IS frames are
formatted as follows and cannot use the Compact Format specified
herein:
+--------------+---------------+--------------+
| TRILL IS-IS | TRILL IS-IS | TRILL IS-IS |
| Link Header | Payload | Link Trailer |
+--------------+---------------+--------------+
Figure 3. TRILL IS-IS Frame
2.2 Ethernet Link TRILL Data Frame General Encapsulation
If the link between neighbor RBridges is Ethernet, then the general
TRILL Data frame format has the following link encapsulation:
Link Header: a 6-byte outer MAC destination address (Outer.MacDA)
followed by a 6-byte outer MAC source address (Outer.MacSA)
followed by an optional 4-byte outer VLAN tag Ethertype and
value (Outer.VLAN), and finally the 2-byte TRILL Ethertype
(0x22F3). Additional tags could be included based on Layer 2
Ethernet functions such a MACSEC [802.1AE].
Under the TRILL standard before this document, the Outer.MacDA
was required to be the unicast MAC address of the destination
RBridge port if the TRILL Data frame was a unicast frame to a
known destination and was required to be the All-RBridges
multicast address if it was a multi-destination frame.
+-----------+------------+- - - - - +-----------+
| MAC Dest. | MAC Source | VLAN Tag | TRILL |
| Address | Address | if Req. | Ethertype |
+-----------+------------+ - - - - -+-----------+
Figure 4. TRILL Data Link Header on an Ethernet Link
Link Trailer: the 32-bit IEEE [802.3] Frame Check Sequence (FCS).
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In the General Format for Ethernet links, the Outer.VLAN can be
omitted when it is not required by VLAN sensitive equipment in the
link.
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3. Compact Format for Point-to-Point Ethernet Links
TRILL Data frames may optionally be sent using a Compact Format if
the link is a point-to-point Ethernet link, Compact Format can be
enabled by both RBridges on the link if other conditions met as
listed below. 16 bytes can be saved per frame as a result.
The Compact Format is simple: the Outer.MacDA, Outer.MacSA, and
Outer.VLAN are replaced by the Inner.MacDA, Inner.MacSA, and
Inner.VLAN and the Inner fields are deleted. This saves 6 + 6 + 4 or
16 bytes. To avoid confusion, Compact Format MUST NOT be used if the
Inner.MacDA is a multi-cast address assigned to TRILL
(01-80-C2-00-00-40 through 01-80-C2-00-00-4F).
Compact Format is not applicable to TRILL IS-IS frames because there
is no inner Ethernet header. (And, of course, Compact Format has
nothing to do with native data or Layer 2 control frames since those
frames are not TRILL frames.)
+---------------------+--------+-----------+---------+---------+
| Ethernet Header | TRILL | Content | Content | Link |
| Header from Payload | Header | Ethertype | ... | Trailer |
+---------------------+--------+-----------+---------+---------+
Figure 5. Compact Format TRILL Data Frame
Compact Format is generally intended for use on physical point-to-
point links between RBridges, a common arrangement in many LANs.
However, if there are any transparent provider bridging devices in
the point-to-point link, such as Provider Bridges or Provider
Backbone Bridges, then the use of the Compact Format will increase
the MAC address learning table stress on such Provider Bridges or
Provider Edge Back Bone bridges.
3.1 Conditions for Using Compact Format
Use of Compact Format is a hop-by-hop decision. In successive RBridge
to RBridge hops, a TRILL Data frame might be sent alternately in
Compact Format and General Format.
There are a number of conditions for using Compact Format TRILL Data
frames. Most of these boil down to maximizing the assurance that the
RBridge-to-RBridge Ethernet link over which the Compact Format TRILL
Data frame is to be sent is really point-to-point. Only the General
Format for TRILL Data frames is safe to use on an RBridge Ethernet
port that is to a multi-access link even if the ports between which
it is being sent have been configured as point-to-point ports. The
following conditions apply. (See also the frame reception process
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variations described in Section 3.3.1.)
o The RBridge port over which Compact Format TRILL Data frames are
to be sent MUST be configured as a point-to-point Ethernet port
(see Section 4.9.1 of [RFC6325]).
o The RBridge port through which the Compact Format TRILL Data frame
is being transmitted MUST be configured to send VLAN tagged
frames. Otherwise the VLAN of the payload may be lost.
o The RBridge port at the other end of the point-to-point link MUST
be announcing that it supports the Compact Format. See Section
3.4.
o Receipt of a native frame indicates that the link is multi-access
and has end stations on it. These are frames that are not Layer 2
control frames (see Section 1.4 of [RFC6325]) and have neither an
Outer.MacDA in the block assigned to TRILL nor an outer payload
EtherType assigned to/for TRILL (currently the TRILL and L2-IS-IS
EtherTypes). On receipt of such a frame, the port MUST stop using
Compact Format TRILL Data frames for at least ten seconds, unless
it is reset by management or rebooted before that.
o Receipt of a TRILL IS-IS Hello frame, other than a point-to-point
Hello from the RBridge believed to be at the other end of the
link, indicates that the link really isn't point-to-point or that
the RBridge at the other end of that link is mis-behaving. In
either case, the RBridge receiving such an unexpected Hello MUST
stop using Compact Format TRILL Data frames on that port for at
least twice the holding time in the unexpected Hello but not less
than ten seconds, unless it is reset by management or rebooted
before that. This is a change to [RFC6325] which states that an
RBridge port configured as point-to-point ignores TRILL Hellos.
o RBridge Ethernet ports are required to monitor ports for BPDUs
received (Section 4.9.3 [RFC6325]). On receipt of a customer
bridging BPDU at an RBridge port, the RBridge MUST stop using
Compact Format on that port and revert to sending General Format
TRILL Data frames for at least four times the Bridge Hello Time in
the BPDU, but not less than ten seconds, unless the port or
RBridge is reset by management or rebooted before that.
o It is RECOMMENDED that RBridge ports intending to use Compact
Format also use the Link Layer Discovery Protocol (LLDP) [802.1AB]
to provide additional assurance that the link is actually point-
to-point. For this use, LLDP should be run to the Nearest Customer
Bridge MAC address (01-80-C2-00-00-00). Receipt by an RBridge port
supporting LLDP of an LLDP message indicating the presence on the
link of a MAC Bridge, Layer 3 Router, or End Station indicates
that the link is not point-to-point and the RBridge MUST stop
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using Compact Format on the port for at least twice the TTL in the
received LLDP frame but not less than ten second, unless the port
or RBridge is reset by management or rebooted before that.
3.2 RBridge Originated and Terminated Native Frames
There can be native frames originated by or intended for consumption
by an RBridge. Examples include SNMP over IP frames or RBridge
Channel frames [RFCchannel]. In many cases, such internal sinks and
sources of native frames are treated as a virtual end-station
internally attached to the RBridge. Such frames are converted to
TRILL Data frames before being transmitted outside the originating
RBridge.
Because of the way that Compact Format TRILL Data frames are
recognized, particularly the change in [RFC6325], Section 4.6.2,
Point 3, made by Section 3.3.1 of this document, an RBridge MUST use
a MAC address different from the address of any of its ports as the
Inner.MacSA of frames it locally originates and as the Inner.MacDA it
expects to see in unicast TRILL Data frames that it receives and
decapsulates for locally processing.
3.3 Compact TRILL Data Reception and Transmission
If an RBridge's Ethernet port has Compact Format enabled, frame
reception and transmission are modified as described below.
Section 4.6 of the TRILL base protocol standard [RFC6325] provides a
specification of the processing of all possible types of received
frames. There is no change in the definition of TRILL frames as
specified in [RFC6325] Section 1.4, that is, TRILL frames are any
frame starting with the TRILL or L2-IS-IS Ethertype or that has an
Outer.MacDA that is any of the block of 16 multicast addresses
assigned to TRILL ([RFC6325] Section 7.2).
3.3.1 Compact TRILL Data Frame Reception
Section 4.6.2 of [RFC6325] specifies the processing of received TRILL
frames. A complete replacement for Section 4.6.2 of [RFC6325] that
supports Compact Format and incorporates the correction in Section
5.1.2 of [ClearCorrect] is provided in the quoted text below.
Even when Compact Format is enabled, the sender is not required to
compact all or any TRILL Data frames and a receiver MUST be prepared
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for an arbitrary mix of Compact Format and General Format TRILL Data
frames arriving on a point-to-point link.
NOTE: All of the Section references in the quoted text below are
references to Sections in [RFC6325].
"A TRILL frame either has the TRILL or L2-IS-IS Ethertype or has a
multicast Outer.MacDA allocated to TRILL (see Section 7.2). The
following tests are performed sequentially, and the first that
matches controls the handling of the frame:"
"By default a frame is classified as General Format."
"1. If the Ethertype is L2-IS-IS and the Outer.MacDA is either
All-IS-IS-RBridges or the unicast MAC address of the
receiving RBridge port, the frame is handled as described in
Section 4.6.2.1 on TRILL Control frames."
"2. If the Outer.MacDA is a multicast address allocated to TRILL
other than All-RBridges then the frame is discarded."
"3. If the Outer.MacDA is a unicast address other than the
address of the receiving Rbridge then (3a) if Compact Format
TRILL Data frames are disabled, the frame is discarded or
(3b) if Compact Format TRILL Data frames are enabled, the
frame is classified as compact."
"4. If the Ethertype is not TRILL, the frame is discarded."
"5. If the Version field in the TRILL Header is greater than 0,
the frame is discarded."
"6. If the hop count is 0, the frame is discarded."
"7. If the Outer.MacDA is multicast and the M bit is zero the
frame is discarded. If the Outer.MacDA is unicast and M bit
is one processing continues if Specific Addressing is
enabled. If Specific Addressing is not enabled, the frame is
discarded."
"8. If the frame has been classified as Compact Format, skip the
rest of this rule and go to Rule 9. By default, an RBridge
MUST discard General Format TRILL Data frames from a
Outer.MacSA that is not an adjacency on the port where the
frame was received. RBridges MAY be configured per port to
accept such frames in cases where it is known that a non-
peering device (such as an end-station) is configured to
originate general TRILL encapsulated data frames that can be
safely accepted."
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"9. If a frame has been classified as a Compact Format TRILL Data
frame but it was received untagged, that is, without an
Outer.VLAN, discard the frame."
"10. For all subsequent processing, including Rule 11, if the
frame has been classified as Compact Format, all references
to Inner.MacDA, Inner.MacSA, or Inner.VLAN are to be
understood to actually refer to the Outer.MacDA, Outer.MacSA,
and Outer.VLAN as the frame was received."
"11. The Inner.MacDA is then tested. If it is the All-Egress-
Rbridges (also known as All-ESADI-RBridges) multicast address
and RBn implements the ESADI protocol, processing proceeds as
in Section 4.6.2.2 for TRILL ESADI frames. If it is any other
address or RBn does not implement ESADI, processing proceeds
as in Section 4.6.2.3 for TRILL Data frames."
3.3.2 Compact TRILL Data Frame Transmission
When a TRILL Data frame is being transmitted out an RBridge port, if
the conditions listed in Section 3 above are met, the frame MAY be
sent in Compact Format.
3.4 Announcing Support for Compact Format
The Compact Format option is a hop-by-hop optional Ethernet link
TRILL frame format and it is possible that an RBridge would support
it on some ports and not others. Therefore, if Compact Format is
enabled at a port, this is indicated in every Hello (Section 6) it
sends out that port.
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4. Specific Addressing
Specific addressing optionally enables more efficient use of some
types of multi-access links.
4.1 Current Multi-Destination Addressing
When multiple RBridges are connected to an Ethernet link, the base
TRILL protocol standard [RFC6325] requires that multi-destination
TRILL Data frames be sent on the Ethernet link addressed to the All-
RBridges multicast address.
If the link is a multi-access link, such as a large bridged LAN, use
of a multicast address may impose a significant burden, causing the
frame to be flooded in the bridged LAN. In addition, all or many
stations attached to the bridged LAN may received the frame using up
some of their input bandwidth. Those RBridges that receive the frame
but are not the next hop on the frame's distribution tree will
discard the frame due to the Reverse Path Forwarding Check.
4.2 Specific Addressing Specification
Multi-destination TRILL Data frames are sent on the distribution tree
identified in the TRILL Header subject to optional pruning. The
transmitting RBridge thus knows which next hop RBridge or RBridges on
the link it needs to get the frame to.
If the next hop RBridges on the multi-access link and the
transmitting RBridge all have Specific Addressing enabled, then the
frame MAY be link unicast to the next hop RBridge or RBridges.
Use of Specific Addressing is a hop-by-hop optional decision.
Successive TRILL Data frames received by an RBridge, even from the
same sending RBridge on the same distribution tree, may be
specifically (unicast) or multicast addressed. (The same frame is
never sent both ways.) In successive RBridge to RBridge hops, a
multi-destination TRILL Data frame might be sent alternately in
specifically addressed and multicast addressed form.
4.3 Announcing Support for Specific Addressing
The Specific Addressing option is a hop-by-hop optional format. It is
possible that an RBridge would support it on some ports and not
others. Therefore enablement of this option is indicated in every
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TRILL Hello (see Section 6) sent on the port.
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5. Interaction Between The Optimizations
Compact Format can only be used for TRILL Data frames on Ethernet
links that are point-to-point. Compact Format works under the
conditions specified above regardless of whether the frame is TRILL
unicast (M=0) or TRILL multi-destination (M=1). It sets the
Outer.MacDA, Outer.MacSA, and Outer.VLAN to the corresponding Inner
fields and removes the Inner fields.
Specific Addressing is only beneficial for frames that are TRILL
multi-destination Data frames on multi-access links. Specific
Addressing causes the frame to be link unicast by setting the
Outer.MacDA to the unicast address of a next hop RBridge.
Both optimizations change the Outer.MacDA from its value in the base
TRILL protocol and thus they conflict. Specific Addressing MUST NOT
be used on point-to-point Ethernet links.
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6. IANA Considerations
IANA is requested to allocate two capability bits in the TRILL-PORT-
VER sub-TLV [RFC6326bis] as follows:
Bit Description Reference
====== ============================== =================
tbd1 Compact Ethernet enabled. (This document)
tbd2 Specific addressing enabled. (This document)
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7. Security Considerations
For general TRILL protocol security considerations, see [RFC6325].
See other security considerations below.
7.1 Compact Format Security Considerations
An RBridge conformant to the TRILL standard that has Compact Format
TRILL Data not implemented or not enabled on a port will, as part of
its normal procedures, discard any Compact Format TRILL Data frame it
receives on that port because the EtherType of the frame would be
TRILL but (1) if the Compact Format resulted in a unicast
Outer.MacDA, it would not be the address of the receiving RBridge
port, and (2) if the Compact Format resulted in a multicast or
broadcast Outer.MacDA, it would not be the All-RBridges multicast
address. If the RBridge port failed to discard the frame and
erroneously handled it as being in General Format, bad things will
usually happen as described in Section 7.3.
With a General Format TRILL Data frame, the VLAN of the data is
somewhat protected in the Inner.VLAN field. With Compact Format, it
is put in more exposed Outer.VLAN field. If it is stripped and the
frame arrives untagged, the rules in this document require that it be
discarded to avoid changing the VLAN labeling of the frame to the
default of the receiving RBridge port.
7.2 Specific Addressing Security Considerations
It is important not to apply both Compact Format optimization and
Specific Addressing optimization to the same frame or else the frame
may be misinterpreted as described in Section 7.3. For this reasons,
use of Specific Addressing on point-to-point links, where it would
not provide an advantage anyway, is prohibited.
7.3 Results of Frame Misinterpretation
For frames that are misinterpreted due to circumstances described in
Sections 7.1 and 7.2, the first six bytes of the native frame content
will be treated as the Inner.MacDA, the next six bytes of that oontnt
as the Inner.MacSA, and the next four bytes as the Inner.VLAN. If the
Ethertype or the Inner.VLAN is not checked or some of the payload
data accidentally has the value of a VLAN tag Ethertype, the payload
may be delivered in the wrong VLAN violating security policy. For
this reason, the provisions of Sections 3 of this document should be
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scrupulously enforced.
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8. References
Normative and informative references for this document are given
below.
8.1 Normative References
[802.1AB] - IEEE, "IEEE Standard for Local and metropolitan area
networks / Station and Media Access Control Connectivity
Discovery", IEEE Std 802.1AB-2009, 17 September 2009.
[802.1Q] - IEEE, "IEEE Standard for Local and metropolitan area
networks / Virtual Bridged Local Area Networks", IEEE Std
802.1Q-2011, May 2011.
[IS-IS] - ISO/IEC 10589:2002, Second Edition, "Intermediate System to
Intermediate System Intra-Domain Routing Exchange Protocol for
use in Conjunction with the Protocol for Providing the
Connectionless-mode Network Service (ISO 8473)", 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.
[RFC6325] - Perlman, R., Eastlake 3rd, D., Dutt, D., Gai, S., and A.
Ghanwani, "Routing Bridges (RBridges): Base Protocol
Specification", RFC 6325, July 2011.
[RFC6326bis] - Eastlake, D., Banerjee, A., Dutt, D., Perlman, R., and
A. Ghanwani, "TRILL Use of IS-IS", draft-eastlake-isis-
rfc6326bis, work in progress.
[ClearCorrect] - draft-eastlake-trill-rbridge-clear-correct, work in
progress.
8.2 Informative References
[802-2001] - IEEE 802, "IEEE Standard for Local and Metropolitan Area
Networks / Overview and Architecture", 802-2001, 6 December
2001.
[802.1AE] - IEEE 802, "IEEE Standard for Local and metropolitan area
networks / Media Access Control (MAC) Security", 802.1AE-2006,
18 August 2006.
R. Perlman, et al [Page 19]
INTERNET-DRAFT TRILL: Link Data Optimizations
[802.3] - IEEE, "IEEE Standard for Information technology /
Telecommunications and information exchange between systems /
Local and metropolitan area networks / Specific requirements
Part 3: Carrier sense multiple access with collision detection
(CSMA/CD) access method and physical layer specifications",
IEEE Std 802.3-2008, 26 December 2008.
[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.
[RFCchannel] - Eastlake, D., V. Manral, L. Yizhou, S. Aldrin, D.
Ward, "RBridges: TRILL RBridge Channel Support", draft-ietf-
trill-rbridge-channel, work in progress.
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INTERNET-DRAFT TRILL: Link Data Optimizations
Authors' Addresses
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 E. Eastlake 3rd
Huawei R&D USA
155 Beaver Street
Milford, MA 01757, USA
Phone: +1-508-333-2270
Email: d3e3e3@gmail.com
Yizhou Li
Huawei Technologies
101 Software Avenue,
Nanjing 210012, China
Phone: +86-25-56622310
Email: liyizhou@huawei.com
Anoop Ghanwani
Dell
350 Holger Way
San Jose, CA 95134 USA
Phone: +1-408-571-3500
Email: anoop@alumni.duke.edu
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INTERNET-DRAFT TRILL: Link Data Optimizations
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