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Re: Cisco PPP DS-3 limitations - 42.9Mbpbs?
we run HDLC on DS3 and we max at about 40.something too not sure why, i just assume theres either overhead in the frames somewhere or that the cards arent designed to run at line speed we run HDLC, c-bit and CRC16 on PA-2T3+.. be interested if anyone knows how to get the missing 10% :) Steve On Wed, 20 Feb 2002, Ehud Gavron wrote: > > At a recent consulting opportunity, a client was > only getting 40.9Mbps on their DS-3 (clearchannel > DS3 over OC12 to the IP provider). > (PA-2T3 to PA-2T3, unloaded CPU, drops occur when > peak octets out per sec/8=40.9M) > > The client asked us why 40.9 was less than 44.210. > > The IP provider indicated that "Cisco told us the > maximum theoretical rate of an interface doing > DS-3 with PPP encapsulation is 42.9." > > I can't find documentation to the 42.9. > I can't find documentation that indicates that the > PPP overhead is somehow magically excluded from > the IfOctetsIn and Out... > I can't find documentation as to why 40.9 is > the observed rate. > > Frankly, all my DS-3s (HDLC encap) go up to 44.210, > so I was hoping I could share in the collective > wisdom of NANOG readers who have DS-3s to IP > providers, and can provide real observed feedback. > > Please reply privately. Please let me know privately > if you want a summary. Thanks! > > Ehud Gavron > [email protected] > -- Stephen J. Wilcox IP Services Manager, Opal Telecom http://www.opaltelecom.co.uk/ Tel: 0161 222 2000 Fax: 0161 222 2008