________________________________________ From: [email protected] [[email protected]] On Behalf Of Sambasiva Rao MANCHILI [[email protected]]
When we are simulating just SIP signalling messages between our two test systems at the rate of greater than 500 UDP packets per second, we observed some of Subscribers fail Signalling.After further investigations it is found that UDP packets are lost consequently Signalling is failing for some subscribers intermittently. _______________________________________________ It's difficult to tell what might be going wrong and what might be done to fix it because UDP is, by specification, unreliable. As a result, various components of UDP implementations (including the transceiver hardware, the low-level drivers, and the UDP stack, often feel free to cope with various problem situations by discarding packets. After all, you are dealing with a data flow of maybe 5 megabits per second. If you want reliable transfer of data at speeds comparable to the capacity of the system, you need to use a protocol with reliability features. Another question to ask is what is the overall packet loss rate. You should be seeing losses less than 1%, and given that SIP will retransmit UDP requests, no single UA should see a large enough string of losses to cause failure of signaling. Perhaps the UAs do not retransmit UDP requests like they should? Dale _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
