This release focuses on numerous additional fixes to Shadow's TCP stack, including:
- Tracking TCP connections by 5-tuple
- Corrects default buffer sizes to allow for full link utilization on high bandwidth links
- Packet retransmit timers are now started when packet is sent to network (rather than when buffered)
- Control packets (e.g. ACKs with no payload) now have best priority
- Delayed ACKs are now used to reduce overhead from control packets
- TCP congestion control state machine has been refactored and corrected
- Added explicit duplicate ACK flag and associated processing
This code has been used to run several ShadowTor experiments and has been found to produce more accurate results than previous versions of Shadow.