> which you can then turn into VoIP connections to either phones, or other
> PBXs within your organization.
If you don't have the budget for a full T1, you could look at having it
channelized. Instead of teh full 26, you might only need 4 or so...or
perhaps someone close to you have a T1 that you can share?
> PBXs within your organization.
If you don't have the budget for a full T1, you could look at having it
channelized. Instead of teh full 26, you might only need 4 or so...or
perhaps someone close to you have a T1 that you can share?
when you pick up the phone and speak, your voice occupies 4khz bandwidth. To accurately reproduce any 4khz signal you sample it at twice the peak freq - which gives you 8000 samples per second. Each sample is coded using 8 bits giving you the 64kbps standard unit of capacity- also known as a primary DS-0 signal. A DS-1 is a collection of 24 DS-0 lines or 24 phone lines. A DS-1 when delivered through a copper twisted pair line is called a T1. But now people are calling any data pipe with a 24*64kbps + 8bit overhead signalling ~1.5mbps channel capacity (not bandwidth) as a T1 line.
All telcos that have copper access to your premises (which in calgary would be the ILEC - telus or someone big like that) will offer you a T1 line. Thus you can buy a T1 line with less than 24 active channels and to share the T1 you still need T1 terminating equipment at the other end.
ok - enough about T1s. Why buy a T1 when you can get the same 1.5mbps type of capacity using DSL or cable? Or in other words, why pay a heck of a lot to get a T1 instead of just saddling your phones on a DSL type line ? T1s are time and bit synchronous - meaning, it doesnt matter if you use the line or not, T1 terminating equipment is always sending and receiving bits to keep both ends in exact sync. Also T1s offer you a precise and guaranteed
1.5mbps bidirectional connection. T1s also come with an Availability guarantee - i.e. if the T1 is down for more than a few seconds a year, the Telco will usually compensate you. T1s are therefore highly reliable and highly available. A DSL line is also digital and can give you the same kind of channel capacity, but as soon as you hit the DSLAM, your data is statistically multiplexed with other data streams. Thus you share the outgoing digital 'trunk' from the DSLAM, and quality of service is generally best-efforts. DSL is far less reliable and available but can be had for 40 bucks a month. Cost wise - youre looking at atleast $2000+ or so to build the ckt to your premises, and a few hundred dollars to rent the CPE and a few hundred dollars a month for T1 service. I seem to remember that Terrago had the vanilla package for about $350 a month just for
service.T1 prices are also regulated and you still have to pay more for internet gateway services in addition to the T1, if you plan to use the T1 for data services. (T1 is definitely overkill for just e-mail and surfing)
Ive always wondered why you need to terminate PSTN access into a VOIP box with a reliable T1 while on the other end, your customers access the voip box through regular unreliable internet ? i.e. the performance bottleneck would be the internet - so why not just have PSTN termination to the VOIP box over the internet as well ? If such a termination 'box' (dont know what its called) could be colocated at Telco premises, you would really get away without paying for a T1 line all the way to your location. If a VOIP user calls a PSTN user, the clicks and the echos are a result of the bad quality of the internet connection between the VOIP user and the VOIP server and has nothing to do with the PSTN to VOIP svr connection itself. Might be worth checking out.
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