TCP and WAN issue

Philip Lavine source_route at
Tue Mar 27 21:57:09 UTC 2007

I have 2 data transmission scenarios:

1. Microsoft MSMQ data using TCP
2. "Streaming" market data stock quotes transmitted via a TCP sockets


----- Original Message ----
From: William F. Maton Sotomayor <wmaton at>
To: Philip Lavine <source_route at>
Sent: Tuesday, March 27, 2007 2:50:44 PM
Subject: Re: TCP and WAN issue

Hi Philip,

     We've run across this problem from one end of Canada to the other. 
As others have alluded to, the best you can hope for is to tweak the TCP 
window sizes up and increase the socket buffers to suit.  However, if 
you're doing something over NetBIOS, it's turned out to be a total lost 
cause.  Right now we're looking at the Steelheads from Riverbed to solve 
the NetBIOS problem.  (The Steelheads do the dirty work of TCP tweaking on 
your behalf, so you don't have to, besides cacheing.)

     BTW, when you say stream, you're saying transfer of data other 
than a webcast, correct?

On Tue, 27 Mar 2007, Philip Lavine wrote:

> This is the exact issue. I can only get between 5-7 Mbps. So the question is really what incremental performance gain do WAN accelerators/optimizers offer? Can registry/OS tweaks really make a significant difference because so far with all the "speed enhancements" I have deployed to the registry based on the some of the aforementioned sites I have seen no improvement.
> I  guess I am looking for a product that as a wrapper can multiplex a single socket connection.
> Philip
> ----- Original Message ----
> From: Robert Boyle <robert at>
> To: Philip Lavine <source_route at>; nanog <nanog at>
> Sent: Tuesday, March 27, 2007 2:04:20 PM
> Subject: Re: TCP and WAN issue
> At 04:26 PM 3/27/2007, Philip Lavine wrote:
>> I have an east coast and west coast data center connected with a
>> DS3. I am running into issues with streaming data via TCP and was
>> wondering besides hardware acceleration, is there any options at
>> increasing throughput and maximizing the bandwidth? How can I
>> overcome the TCP stack limitations inherent in Windows (registry
>> tweaks seem to not functions too well)?
> You will have problems obtaining anything more than 5-7Mbit/s based
> on 1500 byte Ethernet packets and a RTT latency of 70-90ms. You can
> increase your window size or use Jumbo Ethernet frames. Almost all
> GigE gear supports jumbo frames. I'm not sure of your application,
> but without OS tweaks, each stream is limited to 5-7Mbit/s. You can
> open multiple streams between the same two hosts or you can use
> multiple hosts to transfer your data. You can utilize the entire DS3,
> but not without OS TCP stack tweaks or a move to jumbo frames. You
> can also use UDP or another connectionless packet method to move the
> data between sites. Good luck.
> -Robert
> Tellurian Networks - Global Hosting Solutions Since 1995
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