@Rich, so far the v6 stacks are still in their infancy. They'll get smaller as soon as we figure out the bare minimum for comms and offload most of the bookkeeping to a gateway. That's what 6LoWPAN does.
NASA's Orion Flight Software Production Systems Manager Darrel G. Raines joins Planet Analog Editor Steve Taranovich and Embedded.com Editor Max Maxfield to talk about embedded flight software used on the Mars on EE Times Radio. Live radio show and live chat. Get your questions ready.