TCP UTO - Weekly Report 2

Catalin Nicutar catalin.nicutar at
Tue Jun 7 09:34:49 UTC 2011


This is the second report for TCP UTO.

* Short TCP UTO description

UTO stands for User Timeout Option (it is described in RFC5482). TCP UTO
specifies a peer should be allowed to advertise its chosen `User Timeout'
for a connection.
The wiki page for this project:

* Work completed this week

I have added the following sysctls:
       net.inet.tcp.uto.enable            (global enable)
       net.inet.tcp.uto.adv_timeout    (default advertised timeout)

I have added the following socket options (IPPROTO_TCP):
       TCP_SNDUTO (local enable + specify advertised timeout)
       TCP_RCVUTO (enable accepting UTO suggestion)

Obviously things may change (I may have to add / remove options, change
semantics, names etc) but this is what I feel is needed for now.

* My goals for this week:
       * Send the TCP UTO option (correct packing with respect to other
       * Test the TCP option with tcpdump / other sniffers

This is all for report 2. If you have questions, suggestions or advices
drop me an email to cnicutar at

Catalin Nicutar

More information about the soc-status mailing list