Deciding When to Use Network-Qualified Names

With support for network-qualified names, system management becomes easier for installations with frequently changing network configurations. Regardless of the frequency of network changes, consider enabling APPC/MVS LUs to use network-qualified names if Allocate calls in TPs or side information for your installation's systems use such names.

If your installation's configuration is relatively stable, however, simpler system management might not be worth the effects of the following security restrictions:

Security management is limited to defining LU-to-LU access authority through RACF® APPCLU profiles. RACF APPL and APPCPORT profiles do not support network-qualified LU names, so your installation must have unique network LU names for each LU to reliably:
- Limit access to a specific local LU from a specific partner LU, or
- Limit access to the local system from a specific partner LU.
Security management for persistent verification is unpredictable as well, because only the network-LU-name portion of an LU name is used to verify persistent verification requests. Without unique network LU names, LUs might, for example, accept conversations from the wrong partner LUs.
Because of this unpredictability, IBM® does not recommend the use of APPC/MVS support for network-qualified names for those LUs that your installation uses for persistent verification requests.