On Mon, 23 Aug 2004, Jiri Kuthan wrote:
Perhaps instead of a UDP packet with no content, a SIP OPTIONS request could be sent by SER. This could perhaps be an selective flag associated with the NAT support in SER, so that either the dummy packet or the OPTIONS packet could be transmitted by the module.
There are other solutions here, like reducing the interval of REGISTER requests to serve the same purpose of refreshing NAT table mappings. However, one could argue that this method has a much higher load than an OPTIONS packet, especially when scaling across thousands or tens of thousands of clients in an environment where external databases (i.e. Radius, SQL, etc) are used for authentication lookups.
I would like that better. We could perhaps mitigate the performance penalty by granting re-REGISTERs which don't change too much -- that could be possible done as authentication-less in-memory lookup.
That's like known SBCs work. Before, they sent an OPTIONS packet but last software versions modify the Expire of the 200 OK from REGISTER so is the UA the one that sends a new REGISTER and generates traffic from the internal side every 30 seconds. These REGISTER are not forwarded to the proxy. The SBC keeps a table where saves the "real" REGISTER expire sent to the proxy. This way you don't flood the proxy with all those REGISTER.
Saludos JesusR.
------------------------------- Jesus Rodriguez VozTelecom Sistemas, S.L. jesusr@voztele.com http://www.voztele.com Tel. 902360305 -------------------------------