[ih] Variable DSCP Values Per Flow

[Timothy J. Salo]

I had always assumed that the DSCP value (and the TOS value before that)
was supposed to remain constant over the life of a flow (five-tuple).
However, I couldn't find this restriction actually written down.

Is there any prohibition in the various specifications against changing
the DSCP value within a flow, perhaps per packet?

Has anyone tried doing this to, for example, request the network to
treat packets within a flow differently?

I suppose the same question could be asked about the IPv6 flow label.

Thanks,

-tjs