Different process of archiving messages in SAP PO/B2B

Hi Experts,

After going through a lot of blogs, I have few queries related to archiving of general messages & EDI transactions.

1) We have three process for archiving -

     *Through Archival Module & Archival Mapping

     *Archiving through AS2 adapter channel configuration

     *Archiving set-up through NWA

Which one is the best way of archiving EDI transactions? What are the limitation of the different methods? Which is the preferrable one?

2) Is archiving important to configure? If not configured what can be the consequences?

3) What should be the appropriate retention period for EDI messages?

4) Archived messages can be accessed for how long?

5) All EDI transactions to be archived indefinitely, is this the right approach?

Please let me know your inputs on the above points.

Thanks,

Nidhi Srivastava