Eliza,

It may help if you think of LAN-free backup as client-to-device data
movement, and server free backup as device-to-device data movement.

In the case of LAN-free backup, the Storage Agent code (a stripped-down
version of the TSM server) is running on the client, consuming memory and
CPU resources when redirecting the data from disk to the SAN-attached
tape.  The data does have to be channelled through the client, then (back)
through the SAN to the tape in the shared library.

Server-free backup would take the resources of the client almost entirely
out of the picture; the client would only transfer the metadata across the
LAN.  But we're not there yet...

Ted