North American Network Operators Group
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Re: BCP regarding TOS transparancy for internet traffic

  • From: Fred Baker
  • Date: Wed May 25 14:23:17 2005
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On May 25, 2005, at 10:39 AM, Sam Stickland wrote:
While it's true that IP is end-to-end, are fields such as TOS and DSCP meant to be end to end? A case could be argued that they are used by the actual forwarding devices on route in order to make QoS or even routing decisions, and that the end devices shouldn't actually rely on the values of these fields?
It used to be that TCP would reset a session if the TOS byte changed in mid-session. That certainly sounds like an end-to-end expectation.