Preferred transport for SIP with CVP 10.5, UDP or TCP?

[Dale Beachwood]

We are in the process of upgrading our 8.5(x) UCCE/CVP environment and I am interested in what the current Cisco preference is for transport for SIP with CVP 10.5, UDP or TCP?  Prior to CVP 8.0 it was UDP but with CVP 8.0 Cisco changed  the preferred transport to TCP due to "issues CVP running on VMware" (BRKCCT-2020.pdf).  My understanding was that this was resolved after CVP 8.5(x) was released, but by that time we were live with CVP 8.5(1) using TCP SIP.  We are now in the process of deploying CVP 10.5(1) and I would prefer to switch to UDP unless there is still a compelling reason to use TCP.  I would appreciate any input on this.

Thanks,

Dale

[Abu Hadee]

Hi Dale

UDP is always the preference unless there are other issue (defect on product or network).

Sometimes, the decision is also depends on the network you are running the contact center. Do you have mismatch MTU between the devices CVP interacts? If packets are fragmented in the network, TCP would be right choice. Also, what is the size of the SIP packets? If the size is too big, it will switch to TCP any way irrespective of what is your preferred protocol.

- Abu

[Chris Deren]

TCP is the preferred protocol on current versions.