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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: MCI
> > > What kinds of routers can route at near wire speeds a bunch of ports at > > > 155Mb ATM? > > > > None right now. Gigarouter can handle it theoretically, but... > > > > I'm being picky, but it's a moot question since doing wirespeed OC3c using > > ATM is impossible in of itself. Hell, mapping of > > SONET framings to ATM cells take off about 6 mbps right there. > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ By the way, I did not post the above.. [email protected] (Shikhar Bajaj) wrote: > A couple of minor corrections here. ATM cells are mapped into SONET frames and > not the reverse. Also, I presume that the 6 Mbps that you are talking about is that > the ATM bit rate over an OC-3 is 149 Mbps as opposed to the OC-3 pipe > rate of 155 Mbps. Those 6 Mbps are taken up by the SONET management overhead > (section, line, and path) in the frame. This is independent of whatever goes in the > SONET payload envelope and has nothing to do with ATM. It seems to me that Sonet OC-3 is often taken as transport for 3 DS3s, which would reduce 155.530 Mbps to 134.208 Mbps (3 x 44.736 Mbps), less than the 149 Mbps you cite above. Do you have a good recommendation for Gordon Cook, TCP/IP direct over Sonet? Thank you for posting, Wolfgang Wolfgang Henke [email protected] . http://www.whnet.com/wolfgang/ WH Networks ... ftp.whnet.com /pub/wolfgang 2672 Bayshore Parkway Suite 503 ....... +1 415 390 9316 Mountain View CA 94043 ................... fax +1 415 390 9317
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