Which of the following are you interested in?

1) encrypted files which an Avamar client will back up to an Avamar server

2) "in-flight" encryption of data between an  Avamar client & Avamar server

3) "at-rest" encryption of data as stored on an Avamar server

I realise this thread is quite old but rather than start a new one for the same question can anyone tell me:

Does turning the encryption setting to 'None' for a backup group (eg encryption of a backup) increase the performance of the backup in terms of time taken to complete?

If so is the difference significant?

Disabling encryption for backups running across a LAN is unlikely to improve backup performance. The bottleneck for backup performance is generally the client filesystem I/O performance which is typically in the 100 GB/hr to 300 GB/hr range. For gigabit Ethernet connections, the raw throughput will be around 350GB/hr and Avamar compresses data by a factor of roughly 2:1 so our logical network throughput will be in the 700GB/hr range. If the I/O performance is the bottleneck, turning off encryption won't gain you anything.

For backups running across a WAN or a slow LAN link, the network may be the bottleneck in which case disabling encryption may give you a performance boost but it's unlikely to be significant -- probably less than 10%.