On Mon, 2008-03-24 at 14:29 -0400, Alex Balashov wrote: > mark morreny wrote: > > Hi > > > > I am working on deploying voip for my company and would like to seek > > some advice on the number of E1 lines we need to rent. Our telco told > > us that there can be at most 30 concurrent channels on an E1 line. > > Typically, what is the maximum number of DIDs that we can allocate to > > that E1 line before users get frequent "all lines are busy"? We are > > running a support center with mostly incoming calls. Is there any rule > > of thumb that are typically used for this kind of estimation? > > That depends on the application. > > In general, phone lines for voice (not fax or modem) are considered to > have a 30:1 oversubscription ratio, but that can vary immensely. > > Also, it is instructive to inquire what portion of the DIDs will be used > with what frequency, and whether the distribution is truly uniform. > VoIP is a DID-intensive industry; often, DIDs are assigned to every > employee in an organisation so that everyone has one in principle, even > if relatively few people actually use them. >
At my former employer, a telco equipment supplier, they used for the normal office area a 10:1 oversubscription ratio. For inbound line, like faxes no oversubscription. But that is for any ordinary office with people doing research & development, pre-aftersales support... But for a support centre, you might ask whether you want any oversubscription at all. As the main job for the people is accepting inbound phone calls. Ask yourself (or your team) Should a customer get a message that all staf are busy, (and put them in a waiting queueue with a fifo) or that a customer should get "all lines are busy" and have to dial another fifty time before he gets through... As a customer, i would rather opt for the first one, but can you afford that? hw _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
