Hi Mahesh,

It depends on the actual configuration.

If its a Dynamic NAT or Dynamic PAT then it is not bidirectional because destination hosts cannot initiate connections towards the source hosts in the NAT configuration

If its a Static NAT / Static PAT / Identity NAT / NAT0 configuration then its naturally bidirectional in the sense that both source and destination can initiate the connection.

Though in the case of Dynamic type of NAT/PAT, naturally the return traffic will flow from the destination back to the source using this same translation. So in that sense it bidirectional BUT connections cant be initiated from the destination networks defined in the NAT configuration.

Though I would imagine there are some exception to this depending how the ACLs are configured and what kind of translations are active before the destination network attempts to open a connection. Some existing translation together with the destination interface ACL might make it possible for some connectivity. But in normal situation it wouldnt really be bidirectional.

- Jouni