- (50%) add timers
  - (99% ?) code timer routine (Mikkel)
  - (0%) integrate timers into the transaction layer.

- (0%) automatically add headers like 'Max-Forward: ' ?

- (0%) transport resolver (multiple transports per proto/ip)

- (100%) support record-routing
  -> (100%) copy route header
  -> (100%) compute next hop (w. RR, RURI, contact)

- (100%) generate correct via

- (100%) send 200 ACK