Internet DRAFT - draft-ietf-pim-pop-count
draft-ietf-pim-pop-count
Network Working Group Dino Farinacci
Internet-Draft Greg Shepherd
Intended status: Experimental Stig Venaas
Expires: April 7, 2013 Cisco Systems
Yiqun Cai
Microsoft
October 4, 2012
Population Count Extensions to PIM
draft-ietf-pim-pop-count-07.txt
Abstract
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.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 7, 2013.
Copyright Notice
Copyright (c) 2012 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
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 4
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Pop-Count-Supported Hello Option . . . . . . . . . . . . . . . 5
3. New Pop-Count Join Attribute Format . . . . . . . . . . . . . 6
3.1. Options . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1.1. Link Speed Encoding . . . . . . . . . . . . . . . . . 10
3.2. Example message layouts . . . . . . . . . . . . . . . . . 11
4. How to use Pop-Count Encoding . . . . . . . . . . . . . . . . 13
5. Implementation Approaches . . . . . . . . . . . . . . . . . . 14
6. Caveats . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
8. Security Considerations . . . . . . . . . . . . . . . . . . . 17
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
10.1. Normative References . . . . . . . . . . . . . . . . . . . 19
10.2. Informative References . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20
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1. Introduction
This document specifies a mechanism to convey accounting information
using the PIM protocol [RFC4601] [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.
This mechanism 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.
The sort of accounting data this specification provides, on a per
multicast route basis, are:
1. The number of branches in a distribution tree.
2. The membership type of the distribution tree, that is Source-
Specific Multicast (SSM) or Any-Source Multicast (ASM).
3. Routing domain and time zone boundary information.
4. On-tree node and tree diameter counters.
5. Effective MTU and bandwidth.
This document defines a new PIM Join Attribute type [RFC5384] to the
Join/Prune message as well as a new Hello option. The mechanism is
applicable to IPv4 and IPv6 multicast.
This is a new extension to PIM, and it is not completely understood
what impact collecting information using PIM would have on the
operation of PIM. This is an entirely new concept. Many PIM
features (including the core protocols) were first introduced as
Experimental RFCs, and it seems appropriate to advance this work as
Experimental. Reports of implementation and deployment across whole
distribution trees or within sub-trees (see Section 6) will enable an
assessment of the desirability and stability of this specification.
The PIM working group will then consider whether to move this work to
the Standards Track.
This document does not specify how an administrator or user can
access this information. It is expected that an implementation may
have a command line interface or other ways of requesting and
displaying this information. As this is currently an Experimental
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document, defining a MIB module has not been considered. If the PIM
working group finds that this should move on to Standards Track, a
MIB module should be considered.
1.1. Requirements Notation
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].
1.2. Terminology
This section defines the terms used in this document.
Multicast Route: A (S,G) or (*,G) entry regardless if the route is
in ASM, SSM, or Bidir mode of operation.
Stub Link: A link with members joined to the group via IGMP or
Multicast Listener Discovery (MLD)
Transit Link: A link put in the oif-list (outgoing interface list)
for a multicast route because it was joined by PIM routers.
Note that a link can be both a Stub Link and a Transit Link at the
same time.
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2. Pop-Count-Supported Hello Option
A PIM router indicates that it supports the mechanism specified in
this document by including the Pop-Count-Supported Hello option in
its PIM Hello message. Note that it also needs to include the Join-
Attribute Hello option as specified in [RFC5384]. The format of the
Pop-Count-Supported Hello option is defined to be:
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
OptionType = TBD1, OptionLength = 0. Note that there is no option
value included. In order to allow future updates of this
specification that may include an option value, implementations of
this document MUST accept and process this option also if the length
is non-zero. Implementations of this specification MUST accept and
process the option ignoring any option value that may be included.
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3. New Pop-Count Join Attribute Format
When a PIM router supports this mechanism and has determined from a
received Hello, that the neighbor supports this mechanism, and also
that all the neighbors on the interface support the use of join
attributes, it will send Join/Prune messages that MAY include a Pop-
Count Join Attribute. The mechanism to process a PIM Join Attribute
is described in [RFC5384]. The format of the new attribute is
specified in the following.
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 |
. . .
. . .
. . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The above format is used only for entries in the join-list section of
the Join/Prune message.
F bit: 0 Non-Transitive Attribute.
E bit: As specified by [RFC5384].
Attr Type: TBD2.
Length: The minimum length is 6.
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.
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.
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Flags: The flags field has the following format:
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|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Unallocated/Reserved Flags: The flags which are currently not
defined. If a new flag is defined and used by a new
implementation, an old implementation should preserve the bit
settings. This means that a router MUST preserve the settings
of all Unallocated/Reserved Flags in PIM Join messages received
from downstream routers in any PIM Join sent upstream.
S flag: If an IGMPv3 or MLDv2 report with an INCLUDE Mode group
record 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.
A flag: If an IGMPv3 or MLDv2 report with an EXCLUDE Mode group
record, or 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.
A combination of settings for these bits indicate:
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 using SSM
1 0 All group members are using ASM
1 1 A mixture of SSM and ASM group members
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.
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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
[I-D.ietf-mboned-auto-multicast] protocol.
P flag: This flag is set by a router if all downstream routers
support this specification. That is, they are all PIM pop-
count capable. If a downstream router does not support this
specification it MUST be cleared. This allows one to tell if
the entire sub-tree is completely accounting capable.
Options Bitmap: This is a bitmap that shows which options are
present. The format of the bitmap is as follows:
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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:
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
See Section 3.1 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.
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By using this bitmap we can specify at most 16 options. If there
becomes a need for more than 16 options, one can define a new
option that contains a bitmap, which can then be used to specify
which further options are present. The last bit in the current
bitmap could be used for that option. The exact definition of
this is however left for future documents.
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
Section 3.1 for details on the options defined in this document.
3.1. Options
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. Note that
there is no alignment requirements for the options, so an
implementation cannot assume they are aligned.
Transit Oif-List Count: This is filled in by a router sending a
Join/Prune message indicating the number of transit links on the
multicast distribution tree. The value is the number of oifs
(outgoing interfaces) for the multicast route that have been
joined by PIM plus the sum of the values advertised by each of the
downstream PIM routers that have joined on this oif. Length 4
octets.
Stub Oif-List Count: This is filled in by a router sending a Join/
Prune message indicating the number of stub links (links where
there are host members) on the multicast distribution tree. The
value is the number of of oifs for the multicast route that have
been joined by IGMP or MLD plus the sum of the values advertised
by each of the downstream PIM routers that have joined on this
oif. Length 4 octets.
Minimum Speed Link: This contains the minimum bandwidth rate for
any link in the oif-list and is encoded as specified in
Section 3.1.1. 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 smallest value 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.
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Maximum Speed Link: This contains the maximum bandwidth rate for
any link in the oif-list and is encoded as specified in
Section 3.1.1. 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 largest value 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.
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. For this to work, an implementation needs a
way of knowing that a neighbor or an interface is in a different
domain. There is no standard way of doing this. Length 1 octet.
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.
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.
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.
3.1.1. Link Speed Encoding
The speed is encoded using 2 octets as follows:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Exponent | Significand |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Using this format, the speed of the link is Significand * 10 ^
Exponent kbps. This allows specifying link speeds with up to 3
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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.
Here are some examples how this is used:
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
3.2. Example message layouts
We will here give a few examples to illustrate the use of flags and
options.
A minimum size message has no option flags set, and looks like this:
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A message containing all the options defined in this document would
look like this:
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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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A message containing only Stub Oif-List Count and Node Count would
look like this:
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 |
+-+-+-+-+-+-+-+-+
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4. How to use Pop-Count Encoding
A router supporting this mechanism MUST, unless administratively
disabled, include the PIM Join Attribute option in its PIM Hellos.
See [RFC5384] and [HELLO] for details.
It is RECOMMENDED that implementations allow for administrative
control whether to make use of this mechanism. Implementations MAY
also allow further control of what information to store and send
upstream.
It is very important to note that any changes to the values
maintained by this mechanism 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).
When a router removes a link from an oif-list, it need to 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.
It is RECOMMENDED that the Join Attribute defined in this document be
used only for entries in the join-list part of the Join/Prune
message. If the attribute is used in the prune-list, an
implementation MUST ignore it and process the Prune as if the
attribute was not present.
It is also RECOMMENDED that join suppression be disabled on a LAN
when Pop-Count is used.
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.
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5. Implementation Approaches
This section offers some non-normative suggestions for how pop-count
may be be implemented.
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.
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.
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.
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).
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6. Caveats
This specification requires each router on a multicast distribution
tree to support this specification or else the accounting attributes
for the tree will not be known.
However, if there are a contiguous set of routers downstream in the
distribution tree, they can maintain accounting information for the
sub-tree.
If there are a set of contiguous routers supporting this
specification 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.
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7. IANA Considerations
A new PIM Hello Option type, 29, has been assigned temporarily. The
string TBD1 needs to be replaced with the permanently assigned value.
See [HELLO] for details. Although the length is specified as 0 in
this specifications, non-zero length is allowed, so IANA should list
the length as being variable.
A new PIM Join Attribute type needs to be assigned. The string TBD2
needs to be replaced with the assigned value.
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8. Security Considerations
The use of this specification requires some additional processing of
PIM Join/Prune messages. However, the additional amount of
processing is fairly limited, so this is not believed to be a
significant concern.
The use of this mechanism includes information like the number of
receivers. This information is assumed to not be of sensitive
nature. If an operator has concerns about revealing this information
to upstream routers, or other routers/hosts that may potentially
inspect this information, there should be a way to disable the
mechanism, or alternatively more detailed control of what information
to include.
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9. Acknowledgments
The authors would like to thank John Zwiebel, Amit Jain, and Clayton
Wagar for their review comments on the initial versions of this
document. Adrian Farrel did a detailed review of the document and
proposed textual changes that have been incorporated. Further review
and comments were provided by Thomas Morin and Zhaohui (Jeffrey)
Zhang.
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10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4601] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas,
"Protocol Independent Multicast - Sparse Mode (PIM-SM):
Protocol Specification (Revised)", RFC 4601, August 2006.
[RFC5015] Handley, M., Kouvelas, I., Speakman, T., and L. Vicisano,
"Bidirectional Protocol Independent Multicast (BIDIR-
PIM)", RFC 5015, October 2007.
[RFC5384] Boers, A., Wijnands, I., and E. Rosen, "The Protocol
Independent Multicast (PIM) Join Attribute Format",
RFC 5384, November 2008.
10.2. Informative References
[HELLO] IANA, "PIM-Hello Options",
<http://www.iana.org/assignments/pim-parameters>.
[I-D.ietf-mboned-auto-multicast]
Bumgardner, G., "Automatic Multicast Tunneling",
draft-ietf-mboned-auto-multicast-14 (work in progress),
June 2012.
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Authors' Addresses
Dino Farinacci
Cisco Systems
Tasman Drive
San Jose, CA 95134
USA
Email: dino@cisco.com
Greg Shepherd
Cisco Systems
Tasman Drive
San Jose, CA 95134
USA
Email: gjshep@gmail.com
Stig Venaas
Cisco Systems
Tasman Drive
San Jose, CA 95134
USA
Email: stig@cisco.com
Yiqun Cai
Microsoft
1065 La Avenida
Mountain View, CA 94043
USA
Email: yiqunc@microsoft.com
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