Hello Shekar,
The telnet syntax is wrong.
It should be: telnet <hostname> <port>
Also I noticed in your message that there is a incoherence between what you posted and what is in your screen shot.
ddcecd.sap.net:50013
lpcphxepd.lpxsap.net:50013
Which one is your NWDS server ?
As a very simple starting point, please try and ping from you PC the servers you are trying to connect to. Also ensure that the IP address of the services is in your local hosts file.
KR,
Amerjit