North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: T1 bonding
Is it AT&T? If so, they only use Cisco Express Forwarding on the router, or so that's at least what I was told by the level 1 techs. If packet order reassembly is a an issue and the link is oversubscribed (IE: Heavy VoIP/gaming use), this method isn't the greatest over others like MLPPP, or per-flow CEF, but in 99% of circumstances it works great (and has other advantages). Can you max out the T-1 with two or three separate "flows" (IE: simultaneous transfers?) If so, it is possible that they are doing per flow and not per-packet load balancing. It should be per packet. Call them up. Once you get screened and transferred to a Cisco guy, fire away with your questions -- they know their stuff in my experience. Or if is your equipment, log into the router and see if ip load-sharing per-packet is set (assuming it is CEF), and confirm they did the same. Off topic, but in my experience MLPPP usually does a better job of getting 190% of a T-1's speed with two of them. CEF usually tops out at around 160-170% with a single flow, but will max out with as little as two flows. I don't know why though, and haven't cared since I've never really had a dual T-1 all to myself without any other users. 2.5 megabit seems to be the single flow norm on our AT&T Circuits at 3 AM with no usage., 2.8-2.9 with two or three flows. As for the technical details, here is some reading material that explains it quite nicely. http://www.cisco.com/en/US/products/hw/modules/ps2033/products_white_paper09186a0080091d4b.shtml http://www.swcp.com/~jgentry/cisco/cisco-load.html http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120limit/120s/120s21/pplb.htm Test file here for speed tests: ftp://ftp1.optonline.net/test64 Matt Bazan wrote: Can someone shed some technical light on the details of how two T1's are Matt Bazan wrote: Can someone shed some technical light on the details of how two T1's are
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