[e2e] EC++N

[Matthew Luckie]

> called ECN++ (or whatever)
> 
> ECN++ records the position of the bottleneck in the packet - there are
> several ways that this could be done
> 
> i) route record (problem with option space and with MTU of packet)
> ii) hash the packet header (in the same way as DDOS traceback) and

On a slight tangent, something like this might possibly be useful in a
measurement protocol such as IPMP that requests routers to insert a path
record.

http://www.ietf.org/internet-drafts/draft-mcgregor-ipmp-00.txt
http://www.icir.org/vern/imw-2001/imw2001-papers/85.pdf

It has been noted previously that a 32-bit unsigned integer counting
seconds since 1900 in the path record is probably excessive.  Reducing 
the field to count seconds since midnight requires a 17 bit timestamp.  Of
the remaining 15 bits, you could record TTL using 8 bits and store ECN
using another two bits.

This might be somewhat useful to network operators...