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Re: [reSIProcate] StatelessProxy performance problem



On May 17, 2005, at 03.47, Moshe Matitya wrote:

Thank you for your offer. Please note, however, that I am experiencing this behavior with the StatelessProxy app, not with repro.

Thanks,

Moshe

The most likely culprit for performance problems are slow or poor DNS setup.
For every request of the form:

    sip:user@xxxxxxxx

The stack will do a NAPTR query on host.org, followed by a series of SRV and ultimately A record queries. If you do not have NAPTR or SRV records, this will result in 2 DNS query RTT delays before the A record query. You can avoid this by setting up the DNS records for the SIP server as described in RFC 3263. Additionally, running a 'near' caching nameserver can be a real help. Smarter BIND 8/9 servers will include A records in the SRV results as additional information, avoiding the need to do extra queries.

Alan