basic question: udp or tcp

[a.pijpaert]

Hello

i read in a magazine the following:

“…speech is encapsulated in TCP/IP packets.”

Is this correct? Shouldn’t it say “…speech is encapsulated in UDP/IP packets?

I never really stood still at this, i just always assumed that UDP is used for IP telephone/VoIP.

The only implementation of TCP i can imagine is the sending of the H.232 or SIP or something.

Am i correct?

[jasyoung]

Speech is indeed encapsulated in UDP over IP packets. The actual protocol is called RTP (Real Time Protocol), which itself runs over UDP (although I think it will run over other transports). Some less technical publications will refer to IP as TCP/IP, because that's what some users are more used to hearing.

[dschlenzig]

Here's a link with some more information about UDP/TCP pots used in VOIP

http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_tech_note09186a00801a62b9.shtml.

regards, Daniel