Hi,
according to the RFC:
"When a tag is generated by a UA for insertion into a request or response, it MUST be globally unique and cryptographically random with at least 32 bits of randomness."
But when looking at a sip logfile:
egrep "^From:.*;tag=9d49295bb825210f" /var/log/term.log | wc -l 503
Question: Did i understood something wrong or is the recoccurance of the same tag-id and callid in different sessions voilating the rfc?
Ive found loads of non-uniq call-ids as well as non uniq tags. How is a man supposed to make accounting (besides accounting on the PSTN GW/Voice Switch) when those to identifiers are not globally uniq?
So far ive seen non uniq callids from Grandstream Products and non uniq tags from sipura adapters.
:: arnd ::
The call-id is supposed to be unique across a complete session i.e. INVITE/RINGING/OK/ACK/BYE. If it wasn't then there would be no way to relate the messages as part of the same sequence/call.
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Michael Shuler, C.E.O. BitWise Systems, Inc. 682 High Point Lane East Peoria, IL 61611 Office: (217) 585-0357 Cell: (309) 657-6365 Fax: (309) 213-3500 E-Mail: mike@bwsys.net Customer Service: (877) 976-0711
-----Original Message----- From: serusers-bounces@lists.iptel.org [mailto:serusers-bounces@lists.iptel.org] On Behalf Of Arnd Vehling Sent: Thursday, August 12, 2004 10:47 AM To: serusers@lists.iptel.org Subject: [Serusers] From-Tag/Call-id not uniq?
Hi,
according to the RFC:
"When a tag is generated by a UA for insertion into a request or response, it MUST be globally unique and cryptographically random with at least 32 bits of randomness."
But when looking at a sip logfile:
egrep "^From:.*;tag=9d49295bb825210f" /var/log/term.log | wc -l 503
Question: Did i understood something wrong or is the recoccurance of the same tag-id and callid in different sessions voilating the rfc?
Ive found loads of non-uniq call-ids as well as non uniq tags. How is a man supposed to make accounting (besides accounting on the PSTN GW/Voice Switch) when those to identifiers are not globally uniq?
So far ive seen non uniq callids from Grandstream Products and non uniq tags from sipura adapters.
:: arnd ::
Serusers mailing list serusers@lists.iptel.org http://lists.iptel.org/mailman/listinfo/serusers
For IP-PSTN calls: If you "bad" implemented UAs which use the same call-id and from-tag in multiple calls, you can distinguish from the to-tag, which will be generated by your GW and should be correct (that means different for each call).
regards, klaus
Arnd Vehling wrote:
Hi,
according to the RFC:
"When a tag is generated by a UA for insertion into a request or response, it MUST be globally unique and cryptographically random with at least 32 bits of randomness."
But when looking at a sip logfile:
egrep "^From:.*;tag=9d49295bb825210f" /var/log/term.log | wc -l 503
Question: Did i understood something wrong or is the recoccurance of the same tag-id and callid in different sessions voilating the rfc?
Ive found loads of non-uniq call-ids as well as non uniq tags. How is a man supposed to make accounting (besides accounting on the PSTN GW/Voice Switch) when those to identifiers are not globally uniq?
So far ive seen non uniq callids from Grandstream Products and non uniq tags from sipura adapters.
:: arnd ::
Serusers mailing list serusers@lists.iptel.org http://lists.iptel.org/mailman/listinfo/serusers
-
Arnd Vehling -
Klaus Darilion -
Michael Shuler