Testing Communication !!!

[Bira]

dear friends;
I am a test engineer & new to communication field. Can anyone plz explain what do we test in communication. To elaborate more; let say I have an equipment which communicates to a server placed locally through modbus/RS 232. What should I test specific to communication. One of my friend suggested test for the refreshing rate of the GUI screen. What could be other things?

thanks a lot for your help in advance.

 

[RudyL54]

Test for Signal to Noise ratio. Test for the bandwidth. Find out the bit-error rate if it's digital.