Wireshark-users: Re: [Wireshark-users] netflow v9 SRC_AS_PEER and DST_AS_PEER

From: Bill Meier <wmeier@xxxxxxxxxxx>
Date: Tue, 14 Sep 2010 09:17:19 -0400
kura@xxxxxxxxx wrote:
Hello,

Currently wireshark decodes netflow v9 type=128 as "SRC_AS_PEER" and
type=129 as "DST_AS_PEER". Does anyone know in which RFC or other
documents they are defined?

- from packet-netflow.c:
|static const value_string v9_template_types[] = {
|...
|    { 128, "SRC_AS_PEER" },
|    { 129, "DST_AS_PEER" },

In RFC5102 (for IPFIX) id=128 is defined as "bgpNextAdjacentAsNumber"
and id=129 as "bgpPrevAdjacentAsNumber". I think the former is equal to
"DST_AS_PEER" and the latter is equal to "SRC_AS_PEER".

I'd like to know whether this difference is a bug of wireshark or not.

Regards,

A quick Google for <cisco netflow "source as peer"> shows 24 hits
including the following:

http://www.cisco.com/en/US/docs/ios/fnetflow/command/reference/fnf_02.html

----------
<snip>
Router# show flow exporter export-ids netflow-v9

Export IDs used by fields in NetFlow-common export format:

<snip>

  routing source as                          :    16

  routing destination as                     :    17

  routing source as peer                     :   129

  routing destination as peer                :   128

  routing source traffic-index               :    92

<snip>
---------

I'm a newbie with respect to netflow so I don't know if the two messages are the same in v9 and IPFIX (v10) though I expect so. Further Googling may provide an answer.

That being said: I could imagine displaying the correct name (depending upon the protocol version) if the v9/v10 names are different even if the v9/v10 semantics are the same for a type.

(I'm currently reworking the netflow dissector to fix various bugs and to improve the protocol dissection/display but haven't been looking at the actual types).