On 3/27/07, Lincoln Dale <ltd@interlink.com.au> wrote:
even on "default settings" on a modern TCP stack, getting close to path-line-rate on a 80msec RTT WAN @ DS3 speeds with a single TCP stream should not be that difficult.
the Windows TCP stack as of Windows XP SP2 has some fairly decent defaults. it will do RFC1323 / large windows / SACK., but all of these can be tuned with registry settings if you wish.
I was under the impression that XP's default window size was 17,520 bytes, rfc1323 options disabled. Assuming 80ms and 45Mb/s, I come up with a window size of 440Kbytes required to fill the pipe. At windows default I would only expect to see 220Kbs over that same path. I think even modern *nix OSs tend to have default window sizes in the 64kB region, still not enough for that Bandwidth/delay. -- -Steve