North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Frame Relay encap vis-a-vis point-to-point at UUNET
On Mon, 21 Sep 1998, Barry L James wrote: > Hey all, > > We just got a third T1, this time through UUNet and when I looked > at their router configuration I got a little surprise. We ordered a > point-to-point circuit that is being terminated at their detroit POP. The > configuration, however, sets up the line as a frame relay encap on a > sub-interface (on a Cisco, of course :). When I talked to my UUNet rep he > advised that this was the way "every large ISP did it" which I knew wasn't > exactly true since our MCI and AT&T (just recently transitioned from the > BBN backbone to the AT&T network) does not use this configuration. He > insisted that it was still a point to point and that the frame relay > encapsulation was used to enhance the connection. Well I don't know that this is the way every large ISP does it, but several do. That is at least how I did it with NetRail. You take all your T1 customers into CT3 cards on Cascade 9000s and then connect the 9000 to your routers. > Well, I had him grab an engineer (he was an SE) that could possibly > explain it better to me (since the SE said F/R was used to decrease RIP > broadcasts across their backbone) and the engineer said this (basically): > the circuit is terminated in a cascade 9000 f/r switch (used for port > density) which went to a HSSI interface in a Cisco 7xxx series router > which connected directly to their ATM network. Therefore, the f/r encaps > were needed to speak with the cascade. The engineer advised we had a full > CIR and would not suffer any bandwidth loss from using f/r encap. Correct. > Now, I guess my question is: am I getting sold the brooklyn bridge here? Well no, but it does have some problems. A lot of the Cascades at UUNet are the old HSSI cards and have problems over 30 megs. > I mean, not that I wouldn't like to *own* the brooklyn bridge (well, I'd > rather have the triboro or the washington, but anyway...). Is this f/r > encap going have any adverse affect on the quality of this connection > (assuming that this is *NOT* a point-to-point into a frame cloud) or am I > getting shoveled a load of copralite? Well you should be ok. Sure you MAY run into congestion issues, but you should be ok. > Thanks! ><> Nathan Stratton Telecom & ISP Consulting www.robotics.net [email protected] -- "No king is saved by the size of his army; no warrior escapes by his great strength." - Psalm 33:16 > Barry > > Barry L James | Mikrotec Internet Services, Inc (AS3801) > Director R & D | 1001 Winchester Rd > [email protected] | Lexington KY 40505 > http://www.mis.net/ | 606/266.5925 800/875.5095 > Member AAAI, IEEE # 40277528 > --- > Man will occasionally stumble over the truth, but most of the time he > will pick himself up and continue on. -- Winston Churchill >
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