PPP over dialup failing to transfer tcp packets

Problem statement:

TCP over IP/PPP/Dialup connection failed on terminal, when
Ethernet cable detached

Test1: terminal user application configured to use TCP/IP over PPP over
Dialup. Ethernet cable is detached. Terminal successfully establish modem
and PPP connections, but immediately disconnects before TCP connection
attempt.

Test2: Ethernet cable attached to Hub. Terminal successfully establishes
modem, PPP connections and TCP connection to remote host (over
PPP/dialup).

C++ Code


how we can separate DNS requests for PPP and DNS requests for Ethernet. Now, at this moment, PPP using DNS, which tries to work through Ethernet and this, of course, is incorrect behavior.


any body pls help on this.