[dccp] The RTO=4*RTT thing in TFRC

Hi all, I'm confused by the idea of setting RTO=4*RTT in TFRC. From RFC 3448: -- We further simplify this by setting t_RTO = 4*R. A more accurate calculation of t_RTO is possible, but experiments with the current setting have resulted in reasonable fairness with existing TCP implementations

Re: [dccp] The RTO=4*RTT thing in TFRC

Yes, this could be explained clearer - and probably should be. My thinking was: * The TCP RTO was 3 RTTs+variance term. * TFRC does not usually provide prompt feedback of status from a receiver. It could be up to one RTT later before a sender receives feedback. Hence, NFT is (3RTT)+RTT.