Do the XCOM ports need to be defined as bidirectional to a firewall?

Products

• XCOM Data Transport

Issue/Introduction

XCOM uses by default ports 8044-8047, do they have to be defined as bidirectional to the firewall?

Environment

XCOM r11.6 for Windows

XCOM r12.0 for Windows

XCOM r11.6 for Linux/Unix

XCOM r12.0 for Linux/Unix

XCOM r12.0 for z/OS

Resolution

Not necessarily. Let's look at the following setup:

XCOM Windows=====Firewall Machine=====XCOM Linux

If XCOM Windows has to be able to start a transfer to XCOM Linux AND vice versa, then yes, the Firewall Machine has to be configured bi-directional for ports 8044-8047.

If XCOM Windows has to be able to start a transfer to XCOM Linux but XCOM Linux must be prohibited from starting a transfer to XCOM Windows, then the Firewall Machine has to be configured uni-directional Windows > Linux. A similar uni-directional setup is possible the other way.

Additional Information

With a TCP connection, packets are always moving both ways, otherwise a TCP connection could not even be established. This is not to be confused with a Firewall Machine being configured for a TCP connection in one direction but not in the other, or as the case may be in both directions.