One document matched: draft-ietf-pim-pop-count-03.xml
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<rfc category="exp" ipr="trust200902" docName="draft-ietf-pim-pop-count-03.txt">
<?xml-stylesheet type='text/xsl' href='rfc2629.xslt' ?>
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<?rfc strict="yes" ?>
<front>
<title>Population Count Extensions to PIM</title>
<author surname="Dino Farinacci" fullname='Dino Farinacci'>
<organization>cisco Systems</organization>
<address><postal>
<street>Tasman Drive</street>
<city>San Jose</city> <region>CA</region>
<code>95134</code>
<country>USA</country>
</postal>
<email>dino@cisco.com</email></address>
</author>
<author surname="Greg Shepherd" fullname='Greg Shepherd'>
<organization>cisco Systems</organization>
<address><postal>
<street>Tasman Drive</street>
<city>San Jose</city> <region>CA</region>
<code>95134</code>
<country>USA</country>
</postal>
<email>shep@cisco.com</email></address>
</author>
<author surname="Yiqun Cai" fullname='Yiqun Cai'>
<organization>cisco Systems</organization>
<address><postal>
<street>Tasman Drive</street>
<city>San Jose</city> <region>CA</region>
<code>95134</code>
<country>USA</country>
</postal>
<email>ycai@cisco.com</email></address>
</author>
<author surname='Stig Venaas' fullname='Stig Venaas'>
<organization>cisco Systems</organization>
<address><postal>
<street>Tasman Drive</street>
<city>San Jose</city> <region>CA</region>
<code>95134</code>
<country>USA</country>
</postal>
<email>stig@cisco.com</email></address>
</author>
<date/>
<abstract>
<t>This specification defines a method for providing multicast
distribution-tree accounting data.
Simple extensions to the PIM protocol allow a rough approximation
of tree-based data in a scalable fashion.</t>
</abstract>
</front>
<middle>
<section title="Requirements Notation">
<t>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 <xref target="RFC2119"/>.</t>
</section>
<section title="Introduction">
<t>This draft proposes a mechanism to convey accounting information
using the PIM protocol <xref target="RFC4601"/>
<xref target="RFC5015"/>. Putting the mechanism in PIM allows
efficient distribution and maintenance of such accounting
information. Previous mechanisms require data to be correlated
from multiple router sources.</t>
<t>This proposal allows a single router to be queried to obtain
accounting and statistic information for a multicast distribution
tree as a whole or any distribution sub-tree downstream from a
queried router. The amount of information is fixed and does not
increase as multicast membership, tree diameter, or branching
increase.</t>
<t>The sort of accounting data this draft provides, on a per
multicast route basis, are:</t>
<t><list style="numbers">
<t>The number of branches in a distribution tree.</t>
<t>The membership type of the distribution tree, that is SSM or
ASM.</t>
<t>Routing domain and time zone boundary information.</t>
<t>On-tree node and tree diameter counters.</t>
<t>Effective MTU and bandwidth.</t>
</list></t>
<t>This draft adds a new PIM Join Attribute type
<xref target="RFC5384"/> to the
Join/Prune message as well as a new Hello TLV. The mechanism is
applicable to IPv4 and IPv6 multicast. </t>
<section title="Terminology">
<t>This section defines the terms used in this draft.</t>
<t><list style="hanging">
<t hangText="Multicast Route: ">A (S,G) or (*,G) entry regardless
if the route is in ASM, SSM, or Bidir mode of operation.</t>
<t hangText="Stub Link: ">A link with members joined to the
group via IGMP or MLD.</t>
<t hangText="Transit Link: ">A link put in the oif-list for
a multicast route because it was joined by PIM routers.</t>
</list></t>
<t>Note that a link can be both a Stub Link and a Transit
Link at the same time.</t>
</section>
</section>
<section title="New Hello TLV Pop-Count Support">
<t>When a PIM router sends a Join/Prune message to a neighbor,
it will encode the data in a new PIM Join Attribute type
(described in this draft) when the PIM router determines the
neighbor can support this draft. If a PIM router supports
this draft, it must send the Pop-Count-Supported TLV. The format
of the TLV is defined to be:</t>
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OptionType | OptionLength |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OptionValue |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
<t>OptionType = 29, OptionLength = 4, there is no OptionValue
semantics defined at this time but will be included for
expandability and be defined in future revisions of this
draft. The format will look like:</t>
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 29 | 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unallocated Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
<t><list style="hanging">
<t hangText="Unallocated Flags: ">for now should be sent as 0
and ignored on receipt. </t>
</list></t>
</section>
<section title="New Pop-Count Join Attribute Format">
<t>When a PIM router supports this draft and has determined from
a received Hello, the neighbor supports this draft, it will send
Join/Prune messages that MAY include a Pop-Count attribute. The
mechanism to process PIM Join Attribute is described in
<xref target="RFC5384"/>. The format of the new attribute is
described in the following. </t>
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|F|E| Attr Type | Length | Effective MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Options Bitmap |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options |
. . .
. . .
. . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
<t>The above format is used only for entries in the join-list
section of the Join/Prune message.</t>
<t><list style="hanging">
<t hangText="F bit: ">0 Non-Transitive Attribute. </t>
<t hangText="E bit: ">As specified by
<xref target="RFC5384"/>. </t>
<t hangText="Attr Type: ">2. </t>
<t hangText="Length: ">The minimum length is 6. </t>
<t hangText="Effective MTU: ">This contains the minimum
MTU for any link in the oif-list. The sender of Join/Prune
message takes the minimum value for the MTU (in bytes) from
each link in the oif-list. If this value is less than the value
stored for the multicast route (the one received from
downstream joiners) then the value should be reset and
sent in Join/Prune message. Otherwise, the value should
remain unchanged. </t>
<t>This provides one to obtain the MTU supported by
multicast distribution tree when examined at
the first-hop router(s) or for sub-tree for any router on the
distribution tree.</t>
<t hangText="Flags: ">The flags field has the following
format:
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unalloc/Reserved |P|a|t|A|S|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure></t>
<t><list style="hanging">
<t hangText="Unallocated Flags: ">The flags which are currently
not defined. If a new flag is defined and sent by a new
implementation, an old implementation should preserve the bit
settings. This means that if a bit was set in a PIM Join
message from any of the downstream routers, then it MUST also
be set in any PIM Join sent upstream.</t>
<t hangText="S flag: ">If an IGMPv3 or MLDv2 report was
received on any oif-list entry or the bit was set from any
PIM Join message. This bit should only be cleared when the
above becomes untrue.</t>
<t hangText="A flag: ">If an IGMPv1, IGMPv2, or MLDv1 report
was received on any oif-list entry or the bit was set from any
PIM Join message. This bit should only be cleared when the
above becomes untrue.</t>
<t>A combination of settings for these bits indicate:
<figure>
<preamble></preamble>
<artwork><![CDATA[
A-flag S-flag Description
------ ------ -----------------------------------------
0 0 There are no members for the group
('Stub Oif-List Count' is 0)
0 1 All group members are only SSM capable
1 0 All group members are only ASM capable
1 1 There is a mixture of SSM and ASM capable
]]></artwork>
<postamble />
</figure></t>
<t hangText="t flag: ">If there are any tunnels on the
distribution tree. If a tunnel is in the oif-list, a router
should set this bit in its Join/Prune messages. Otherwise, it
propagates the bit setting from downstream joiners.</t>
<t hangText="a flag: ">If there are any auto-tunnels on the
distribution tree. If an auto-tunnel is in the oif-list, a
router should set this bit in its Join/Prune messages.
Otherwise, it propagates the bit setting from downstream
joiners. An example of an auto-tunnel is an tunnel setup
by the AMT <xref target="AMT"/>
protocol.</t>
<t hangText="P flag: ">This flag remains set if all downstream
routers support this specification. That is, they are PIM
pop-count capable. This allows one to tell if the entire sub-tree
is completely accounting capable.</t>
</list></t>
<t hangText="Options Bitmap: ">This is a bitmap that
shows which options are present. The format of the
bitmap is as follows:
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T|s|m|M|d|n|D|z| Unalloc/Rsrvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
Each one of the bits T, s, m, M, d, n, D and z is associated with
one option, where the option is included if and only if the
respective bit is set. Included options MUST be in the same
order as these bits are listed. The bits denote the following
options:
<figure>
<preamble></preamble>
<artwork><![CDATA[
bit Option
----- ------------------------
T Transit Oif-List Count
s Stub Oif-List Count
m Minimum Speed Link
M Maximum Speed Link
d Domain Count
n Node Count
D Diameter Count
z TZ Count
]]></artwork>
<postamble />
</figure>
See <xref target="options"/> for details on the different
options. The unallocated bits are reserved. Any unknown
bits MUST be set to 0 when a message is sent, and treated as 0
(ignored) when received. This means that unknown options
which are denoted by unknown bits are ignored.</t>
<t hangText="Options: ">This field contains options. Which
options are present are determined by the flag bits. As
new flags and options may be defined in the future, any
unknown/reserved flags MUST be ignored, and any additional
trailing options MUST be ignored. See <xref target="options"/>
for details on the options defined in this document.</t>
</list></t>
<section title="Options" anchor="options">
<t>There are several options defined in this document. For each
option, there is also a related flag that shows whether the
option is present. See the Options Bitmap above for a list
of the options and their respective bits. Each option has
a fixed size.
<list style="hanging">
<t hangText="Transit Oif-List Count: ">This is filled in by a
router sending a Join/Prune message which is equal to the
number of oifs for the multicast route that has been joined by
PIM. This indicates the transit branches on a multicast
distribution tree (no members on the links between this router
and joining routers). This is added to the value advertised by
all downstream PIM routers that have joined on this oif.
Length 2 octets.</t>
<t hangText="Stub Oif-List Count: ">This is filled in by a
router sending a Join/Prune message which is equal to the
number of oifs for the multicast route that has been joined
by IGMP or MLD. This indicates the links where there are
host members for the multicast route. This is added to the value
advertised by all downstream PIM routers that have joined on
this oif. Length 2 octets.</t>
<t hangText="Minimum Speed Link: ">This contains the minimum
bandwidth rate for any link in the oif-list and is encoded
as specified in <xref target="speedenc"/>. The
sender of Join/Prune message takes the minimum value for each
link in the oif-list for the multicast route. If this value is
less than the value stored for the multicast route (the one
received from downstream joiners) then the value should be
reset and sent in Join/Prune message. Otherwise, the value
should remain unchanged. This together with the Maximum Speed
Link option provides a way to obtain the lowest and highest
speed link for the multicast distribution tree.
Length 2 octets.</t>
<t hangText="Maximum Speed Link: ">This contains the maximum
bandwidth rate for any link in the oif-list and is encoded
as specified in <xref target="speedenc"/>. The
sender of Join/Prune message takes the maximum value for each
link in the oif-list for the multicast route. If this value is
greater than the value stored for the multicast route (the one
received from downstream joiners) then the value should be
reset and sent in Join/Prune message. Otherwise, the value
should remain unchanged. This together with the Minimum Speed
Link option provides a way to obtain the lowest and highest
speed link for the multicast distribution tree.
Length 2 octets.</t>
<t hangText="Domain Count: ">This indicates the number of
routing domains the distribution tree traverses. A router
should increment this value if it is sending a
Join/Prune message over a link which traverses a domain
boundary. Length 1 octet.</t>
<t hangText="Node Count: ">This indicates the number of routers
on the distribution tree. Each router will sum up all the
Node Counts from all joiners on all oifs and increment by 1
before including this value in the Join/Prune message.
Length 1 octet.</t>
<t hangText="Diameter Count: ">This indicates the longest
length of any given branch of the tree in router hops. Each
router that sends a Join increments the max value received by
all downstream joiners by 1. Length 1 octet.</t>
<t hangText="TZ Count: ">This indicates the number of timezones
the distribution tree traverses. A router should
increment this value if it is sending a Join/Prune message
over a link which traverses a time zone. This can be a
configured link attribute or use other means to determine
the timezone is acceptable. Length 1 octet.</t>
</list></t>
<section title="Link Speed Encoding" anchor="speedenc">
<t>The speed is encoded using 2 octets as follows:
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Exponent | Significand |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
Using this format, the speed of the link is
Significand * 10 ^ Exponent kbps. This allows
specifying link speeds with up to 3 decimal digits
precision and speeds from 1 kbps to 10 ^ 67 kbps.
A computed speed of 0 kbps means the link speed is
< 1 kbps.</t>
<t>Here are some examples how this is used:
<figure>
<preamble></preamble>
<artwork><![CDATA[
Link Speed Exponent Significand
------------ ---------- -------------
500 kbps 0 500
500 kbps 2 5
155 Mbps 3 155
40 Gpbs 6 40
100 Gpbs 6 100
100 Gpbs 8 1
]]></artwork>
<postamble />
</figure>
</t>
</section>
</section>
<section title="Example message layouts">
<t>We will here give a few examples to illustrate the
use of flags and options.</t>
<t>A minimum size message has no option flags set, and looks
like this:
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|F|E| Attr Type | Length = 6 | Effective MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unalloc/Reserved |P|a|t|A|S|0|0|0|0|0|0|0|0| Unalloc/Rsrvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
</t>
<t>A message containing all the options defined in this
document would look like this:
<figure>
<preamble></preamble>
<artwork><![CDATA[
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|F|E| Attr Type | Length = 18 | Effective MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unalloc/Reserved |P|a|t|A|S|1|1|1|1|1|1|1|1| Unalloc/Rsrvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transit Oif-List Count | Stub Oif-List Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Minimum Speed Link | Maximum Speed Link |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Domain Count | Node Count | Diameter Count| TZ Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
</t>
<t>A message containing only Stub Oif-List Count and
Node Count would look like this:
<figure>
<preamble></preamble>
<artwork><![CDATA[
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|F|E| Attr Type | Length = 9 | Effective MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unalloc/Reserved |P|a|t|A|S|0|1|0|0|0|1|0|0| Unalloc/Rsrvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Stub Oif-List Count | Node count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
<postamble />
</figure>
</t>
</section>
</section>
<section title="How to use Pop-Count Encoding">
<t>A router supporting this draft MUST include PIM Join Attribute
TLV in its PIM Hellos. See <xref target="RFC5384"/> and
<xref target="HELLO"/> for details. </t>
<t>It is very important to note that any changes to the values
maintained in this draft MUST NOT trigger a new Join/Prune
message. Due to the periodic nature of PIM, the values can be
accurately obtained at 1 minute intervals (or whatever
Join/Prune interval used).</t>
<t>When a router removes a link from an oif-list, it must be
able to reevaluate the values that it will advertise upstream.
This happens when an oif-list entry is timed out or a Prune is
received.</t>
<t>It is recommended that the Join Attribute defined in
this draft be used for entries in the join-list part of the
Join/Prune message. If the new encoding is used in the
prune-list or an Assert message, an implementation must
ignore them but still
process the Prune as if it was in the original encoding
described in <xref target="RFC4601"/>.</t>
<t>It is also recommended that join suppression be disabled
on a LAN when Pop-Count is used.</t>
</section>
<section title="Implementation Approaches">
<t>An implementation can decide how the accounting attributes are
maintained. The values can be stored as part of the multicast
route data structure by combining the local information it has
with the joined information on a per oif basis. So when
it is time to send a Join/Prune message, the values stored
in the multicast route can be copied to the message.</t>
<t>Or, an implementation could store the accounting values per
oif and when a Join/Prune message is sent, it can combine the
oifs with its local information. Then the combined information
can be copied to the message.</t>
<t>When a downstream joiner stops joining, accounting values
cached must be evaluated. There are two approaches which
can be taken. One is to keep values learned from each joiner
so when the joiner goes away the count/max/min values are
known and the combined value can be adjusted. The other
approach is to set the value to 0 for the oif, and then start
accumulating new values as subsequent Joins are received.</t>
<t>The same issue arises when an oif is removed from the oif-list.
Keeping per-oif values allows you to adjust the per-route values
when an oif goes away. Or, alternatively, a delay for
reporting the new set a values from the route can occur
while all oif values are zeroed (where accumulation of new
values from subsequent Joins cause re-population of values and
a new max/min/ count can be reevaluated for the route).</t>
<t>It is recommended that when triggered Join/Prune messages
are sent by a downstream router, that the accounting information
not be included in the message. This way when convergence is
important, avoiding the processing time to build an accounting
record in a downstream router and processing time to parse the
message in the upstream router will help reduce convergence time.
An upstream router should not interpret a
Join/Prune message received with no accounting data to mean
clearing or resetting what accounting data it has cached.</t>
</section>
<section title="Caveats">
<t>This draft requires each router on a multicast distribution
tree to support this draft or else the accounting attributes for
the tree will not be known.</t>
<t>However, if there are a contiguous set of routers downstream
in the distribution tree, they can maintain accounting
information for the sub-tree.</t>
<t>If there are a set of contiguous routers supporting this draft
upstream on the multicast distribution tree, accounting
information will be available but it will not represent an
accurate assessment of the entire tree. Also, it will not be
clear for how much of the distribution tree the accounting
information covers.</t>
</section>
<section title="IANA Considerations">
<t>A new PIM Hello Option type, 29, has been assigned. See
<xref target="HELLO"/> for details. </t>
<t>A new PIM Join Attribute type needs to be assigned. 2 is
proposed in this draft. </t>
</section>
<section title="Security Considerations">
<t>There are no security considerations for this design other
than what is already in the main PIM specification
<xref target="RFC4601"/>.</t>
</section>
<section title="Acknowledgments">
<t>The authors would like to thank John Zwiebel, Amit Jain, and
Clayton Wagar for their review comments on the initial versions
of this draft.</t>
</section>
</middle>
<back>
<references title='Normative References'>
&rfc2119;
&rfc4601;
&rfc5015;
&rfc5384;
</references>
<references title='Informative References'>
<reference anchor="HELLO">
<front>
<title>PIM Hello Options</title>
<author surname="IANA">
<organization />
</author>
<date month="March" year="2007" />
</front>
<seriesInfo name="PIM-HELLO-OPTIONS per RFC4601"
value="http://www.iana.org/assignments/pim-hello-options" />
</reference>
<reference anchor="AMT">
<front>
<title>Automatic IP Multicast Without Explicit
Tunnels (AMT)</title>
<author initials="D." surname="Thaler">
<organization />
</author>
<author initials="M." surname="Talwar">
<organization />
</author>
<author initials="A." surname="Aggarwal">
<organization />
</author>
<author initials="L." surname="Vicisano">
<organization />
</author>
<author initials="T." surname="Pusateri">
<organization />
</author>
<date month="March" year="2010" />
</front>
<seriesInfo name="Internet-Draft"
value="draft-ietf-mboned-auto-multicast-10.txt" />
</reference>
</references>
</back>
</rfc>
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