I think you made a typo: G.703 is framed. Refer explanation below. A G.703/G.704 link is an European PCM trunk that consists of 32 timeslots (numbered from 0 to 31) representing channels. Beware of the numbering because some people number differently. One channel is 64kbps, so 32 channels gives 2048kbps. It is called channelised or framed because it is divided into channels; timeslot 0 is used a/o for error correction, alarms and framing.... So you cannot use timeslot 0 for voice, data or signalling: when you order a G.703 channelised (framed) line you can use maximum 31*64 = 1984 kbps for data.
Tip: there are two different types of framing on an E1: framing with crc4 and framing without crc4. It is a common mistake to have different framing types at each end of the link. So don't forget to ask your provider when ordering a channelised link. When you order an unframed link, you get a 2 Mbps link 'without any structure'. At least that's my understanding. It's up to your equipment at both ends to decide how to handle it. You may channelize it if you want to allocate dedicated fractions (=number of timeslots) to for example frame relay PVCs. Or you can configure it in unframed E1 mode, which should provide you with a single channel with a bandwidth of 2048 kbps. At least that is what Cisco for instance claims. However, I don't know whether you really get the full bandwidth. I really doubt it. I've read documentation from other vendors that stated that you will only get 1984 kbps even when using unframed mode. It's one of those things I discussed already with many people and you get different contradicting answers. In my opinion you will only get 1984 kbps, since there is still overhead related to that magic timeslot 0. Let him/her who really knows speak. About the V.35 interface. It is a physical interface and, as far as I know, it is not related to the mode of your E1. A V.35 can provide you access to both channelized and unframed E1s. Your last question: neither mode will affect your services. It should be transparent. Eric Brouwers ----- Original Message ----- From: "Lo Ching" To: Sent: Tuesday, March 18, 2003 4:42 PM Subject: E1 [7:65643] > Dear All, > > I subscribed a E1 line to local carrier and they provided me the following > information. > G.703 (unframed E1) have total 2048kbps but > V.35 (framed E1) have only 1984bps > > Their services make sense? > Or can framed E1 can fully 100% used (ie, 2048kbps)? > Also, G.703 or V.35 will affect the services provided (ie, unframed/framed)? > > TIA. > > Lo Ching Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66189&t=65643 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
