From owner-freebsd-isp Wed May 30 22:15:18 2001 Delivered-To: freebsd-isp@freebsd.org Received: from aries.ai.net (aries.ai.net [205.134.163.4]) by hub.freebsd.org (Postfix) with ESMTP id 41EA237B424 for ; Wed, 30 May 2001 22:15:13 -0700 (PDT) (envelope-from deepak@ai.net) Received: from blood (adsl-138-88-72-27.dc.adsl.bellatlantic.net [138.88.72.27]) by aries.ai.net (8.9.3/8.9.3) with SMTP id BAA04478; Thu, 31 May 2001 01:15:05 -0400 (EDT) (envelope-from deepak@ai.net) Reply-To: From: "Deepak Jain" To: "Tom Samplonius" , Cc: Subject: RE: OC48 interface Date: Thu, 31 May 2001 01:19:05 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 In-Reply-To: Importance: Normal Sender: owner-freebsd-isp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org -----Original Message----- From: Tom Samplonius [mailto:tom@sdf.com] Sent: Wednesday, May 30, 2001 10:34 PM To: bv@wjv.com Cc: Deepak Jain; freebsd-isp@freebsd.org Subject: Re: OC48 interface On Wed, 30 May 2001, Bill Vermillion wrote: > On Wed, May 30, 2001 at 05:36:14PM -0400, Deepak Jain thus sprach: > > > > > SONET is a physical layer protocol that (when implemented) can > > provide switching around cut fiber in sub milliseconds. > > Nice when it works. We lost our DS3 for about 18 hours 2 weeks > ago. Seventeen OC-48 links were cut. When we asked the about the > self-healing, they said, normally it would, but not with the many > gone. I find it funny when people put redundant links right next to the circuit it is protected. Bundles get cut, not individual fibres. The whole idea of self healing ring, is that the redundant fibres be run somewhere else entirely. I know that AT&T Canada put a ring in recently nearby. The two paths are at least a 100 kilometres apart for most of the distance. When it enters the destination city, each path should be in a separate conduit running down different streets. Tom ---- While AT&T Canada may build the ring correctly, there is no telling what will happen to that ring in a year or two. They could split the ring to double their capacity, or companies who lease capacity could lease it in just one path. Companies that buy circuits from the lessor would be screwed in the event of a cut. But I guess everyone already knows this... Deepak Jain AiNET To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message