[pflats]

A little googling shows some interesting info about the ACE request/header. From skimming, it looks like a header compression method for VOIP on cell/lossy connections.

Slide deck: http://www-rn.informatik.uni-bremen.de/ietf/rohc/ace-033100-...

Whitepaper: http://w3.ualg.pt/~bamine/B3.pdf