At 06:37 PM 6/12/2008, you wrote:
I'm looking for input on the best practices for sending large files over a long fat pipe between facilities (gigabit private circuit, ~20ms RTT). I'd like to avoid modifying TCP windows and options on end hosts where possible (I have a lot of them). I've seen products that work as "transfer stations" using "reliable UDP" to get around the windowing problem.
I'm thinking of setting up servers with optimized TCP settings to push big files around data centers but I'm curious to know how others deal with LFN+large transfers.
In our experience, you can't get to line speed with over 20-30ms of latency using TCP regardless of how much you tweak it. We transfer files across the US with 60-70ms at line speeds with UDP based file transfer programs. There are a number of open source projects out there designed for this purpose. -Robert Tellurian Networks - Global Hosting Solutions Since 1995 http://www.tellurian.com | 888-TELLURIAN | 973-300-9211 "Well done is better than well said." - Benjamin Franklin