Re: SIP UDP packet loss?

[Sambasiva Rao MANCHILI <sambainietf@xxxxxxxxx>]

Hallo,

A Correction in my mail

>>This helped the packet loss to reduce by 70% but could not achieve 0% packet loss .

This helped the packet loss to reduce by 10%. 

Before increasing buffers we have Faults rate of ~8 to 10% after increasing buffers we have fault rate of 0.9%.
Thank you,

Samba.

On Sat, Mar 19, 2011 at 12:13 PM, Sambasiva Rao MANCHILI <sambainietf@xxxxxxxxx> wrote:

Hallo  Sip Experts / Transport Group Experts,

I am not a SIP expert of application layer. I am part of Test System Development where we simulate the SIP traffic over different transport types like UDP,TCP and SCTP.

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.

To overcome this we then increased the udp.recvspace and udp.sendspace and socketbuffer size in our Networking stack. 

This helped the packet loss to reduce by 70% but could not achieve 0% packet loss .  

Qeury 1:- Is increasing buffer space is a solution or workaround for our Network stack  to overcome packet loss ?

Default values of our Network stack  were 40K for udp.recvspace and 9K for udp.sendspace and socketbuffers are 256K.  

We changed these values in our Network stack  to 256K  for udp.recvspace, 256K for udp.sendspace and socketbuffers to 1024K. 

This change has reduced packet loss but can could not make 0% packet loss.  

Query2:- Can you please suggest us what should be the right values for such buffer space if this is right approach ?

We have yet to enable the voice transmission as a next immediate step, then again SIP RTP UDP packets will further increase based on the codec chosen and this will

cause even more packet loss.

Query3:-  What is the ultimate  solution for eliminating packet loss both on Signalling and on speech path ? 

Thank you in advance for your time.

Samba.

_______________________________________________
Ietf mailing list
Ietf@xxxxxxxx
https://www.ietf.org/mailman/listinfo/ietf