i'm very much familiar with HTTP virtual service but not TCP/IP VS.
How TCP/IP virtual service is different from HTTP. could you please help me understand on this?
Most of the concepts are the same - recording in TCP will be very familiar to you, you'll still select data handlers, etc.
The biggest difference is that all HTTP messages tell you exactly how long they are. A raw TCP message can be in pretty much any format.
If you're lucky, your messages will be delimited using a built-in format (like fixed length messages, linefeed delimited messages, etc.)
Virtualize TCP - DevTest Solutions - 10.3 - CA Technologies Documentation
Otherwise, you'll need to implement your own TCPDelimiter (which isn't hard).
Lastly, TCP protocols often don't send messages as XML, JSON, or some other easily parrseable format. The built in data handlers might not suit your needs. You may need to build a customer data handler.
Here are instructions on making a TCP recording:
TCP Transport Protocol - DevTest Solutions - 10.3 - CA Technologies Documentation