Microsoft tweaks TCP stack in Windows Server and Windows 10

Datetime:2016-08-23 03:39:28          Topic:          Share

Microsoft has announced it will add five new features – some experimental - to the TCP stack it will ship in Windows Server 2016 and the Anniversary Update to Windows 10.

Redmond says the following five features will make it into its new TCP stack:

  1. TCP Fast Open (TFO) for zero RTT TCP connection setup. IETF RFC 7413
  2. Initial Congestion Window 10 (ICW10) by default for faster TCP slow start
  3. TCP Recent ACKnowledgment (RACK) for better loss recovery (experimental IETF draft)
  4. Tail Loss Probe (TLP) for better Retransmit TimeOut response (experimental IETF draft)
  5. TCP LEDBAT for background connections IETF RFC 6817

Microsoft says the changes are needed “to reduce latency, improve loss resiliency and to promote better network citizenship.” It's hard to argue against any of those goals, or the outcomes these additions will allow.

TCP Fast Open, for example, should reduce latency for web traffic. The change to the Initial Congestion Window, for example, is being done “to keep pace with the increased emission rates of network routing equipment used on the Internet today.”

“RACK” can find missing packets with fewer ACKs, while LEDBAT will stop Windows competing aggressively for bandwidth during times of high latency.

Microsoft's tapping into ideas from others with these changes: four of the five come by way of people from Google * . The fifth was submitted to the IETF from folks at the University of Stuttgart, Franklin and Marshall College, and BitTorrent Inc. Yes, that BitTorrent.

Redmond's networking team has let it be known that these changes are just “the first wave of features in the pipeline of upcoming Windows Redstone releases.” So it seems like we'll soon see more enhancements to Windows networking.

That's not an unambiguously good thing because Redmond's post points out that reaping the rewards of its changes will mean some changes to your systems. On the upside, who can argue against faster networking? Not Microsoft. And not just because it wants us all in the cloud. ®

* IETF documents mention the employers of people who propose standards, but that mention doesn't mean a company backs the proposal.