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Re: [PATCH 0/7] [DCCP]: Fixes and enhancements

Hi Ian,

I am cc'ing the IETF list regarding one point in your recent mail, which I found a little confusing.

Ian McDonald wrote: 
The calculation is based on the work Padhye et al did in this paper -
http://citeseer.ist.psu.edu/padhye98modeling.html

As it turns out this is based on TCP Reno at that time and modern TCP
variants are more efficient when dealing with loss as can be verified
through iperf but we should implement what the RFC says.


Is this really so?

Sally will correct me when I no doubt misspeak, but I believe the difference between NewReno and Reno is that NewReno makes it more likely that multiple losses in a single RTT will be treated as a single loss event, through modifications to fast recovery.

In DCCP CCID 3 these issues do not exactly arise. The receiver explicitly reports loss *intervals*. The receiver can, and should, use SACK/NewReno algorithms to determine those loss intervals.

So it is possible that CCID 3 will send slower than TCP but I don't think this is the reason. The reason should be investigated.

Eddie