Intermittent Timeout Issue when the nodes are located in different networks

Hi Team,

I have Couchbase Nodes in a separate network and Application nodes/vm in separate newtwork

I have checked ping command and telnet command are working.
Still the application is giving Intermittent Timeout Issue .

When I moved the Application node to another node in same network as Couchbase node then it seems to work as expected.

What should I check between these two nodes in different network.
Can you give me some pointers to resolve this issue in permanent manner.