North American Network Operators Group
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Re: Current street prices for US Internet Transit

  • From: Deepak Jain
  • Date: Tue Aug 17 17:25:39 2004 


I've had this discussion a few times with people working at cisco. The
answers I usually get has to do with how well it handles overload, ie what
happens when ports go full.



If you want to be able to do single TCP streams at 5 gigabit/s over your

long-haul 10gig network that is already carrying a lot of traffic, you

need deep packet buffers. If your fastest customer is less than 1gig and

your network is 10gig, you do not.



So, if I were to provision a transatlantic line that cost me a lot of

money, I would use a GSR or a juniper. If I were to provision a 80km dark

fiber between two places where I already own 24 pairs, there is a wide

choice in equipment.



Maybe I am wrong here, but what does the router's packet buffers have to
do with a TCP stream? Buffers would add jitter and latency to the pipe.
Wouldn't a 5Gb/s TCP stream over 3000+ miles imply huge buffers on the
sender and receiver side? Since when do the routers buffers make a
difference for that? If your application is such that jitter and latency
don't matter, buffers are great. If dropping a packet on congestion is
worse than queuing it, also great. But how does that improve the
stream's performance otherwise?



"What happens when ports go full" are you implying some kind of HOL
problem in the 7600?



DJ