### Description Not shure is this relevant issue. according to rfc3261:
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.
Kamailio has 16 instead and distribution is not good. I look at tags for 419485 sip flows (different callid) and table below (top keys ordered by count): tag suffix; count for different flows with this suffix ed54 6258 d118 5988 56ce 5923 a7a5 5220 de51 2150 82d8 1143 cf52 890 af92 740 7b5f 534 85f7 307 e553 163 7f7e 138 1d55 130 1afe 62 5a69 43 7caa 18 8474 18 9db2 18 11d3 18 f9ff 18 5420 17 dae6 17 908d 17 ede4 17 09ee 17 96be 17 25dc 17 af6d 16 2506 16 3da0 16 f161 16 1c29 16
#### SIP Traffic To: sip:039*101@host:5071;tag=555d2c3eafafcba8ac92b676e91bb6ed.58eb
Probably those tag generation functions that are quite old need to be revised a bit. Anyone willing to propose an enhancement to it, is welcome to jump on board and discuss here/send a patch.
I implemented a improved version of the current to tag generation algorithm in git master by more or less doubling the output of the existing code and including the callid body as well. I think this should improve it considerable for now.
I implemented a similar improvement for uac requests from tm as well by doubling the output and also including some more data (request uri) in it. This should also help e.g. for outgoing REGISTER requests from uac module.
So the from-tag suffix is now as well 32 bits, the first half of the suffix stays the same as in the core part. If e.g. some other tools match to this suffixes, they should probably still continue to work.
I will look to it again in the next development cycle, as at least SHA1 should be used as a hash function for both prefix and suffix. But this will be a more risky change, so better do it later with more time for tests. I will create a new issue for this together with some other changes.
Close this one for now.
Closed #1164.
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Daniel-Constantin Mierla -
Dmitri Savolainen
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Henning Westerholt