Around the time you posted the above message, there was a major change in the AirTel GPRS network. It could be related to your problem too.
But, first, has your issue been solved? Please let me know.
The technical change was: (this part is quite techy - you may skip it)
My P2P application logged into the server but the connection drops soon after connecting. TCP-ReSeTs were sent terminating the connection. This happened when a >1488 byte packet was sent out from my connection resulting in an AirTel intermediate router sending ICMP: Packet needs to be fragmented AND soon after that, the Resets were sent causing the failed connection.
Solution for PPP:
Change the MTU for PPP connections from the Default (1500) to 1488 bytes.
»
support.microsoft.com/de ··· s;826159The above link explains how to do it. If you have any questions, please ask me further and I will try to help. I do not know whether AirTel has re-allowed 1500 byte packets but I am not taking any risks. Since the incident, I am using 1488 byte packets max.