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IBM To Run VoIP On Linux
hrhsoleil writes "Johnny Barnes, IBM's vice president of global IT solutions and standards, told attendees at a TechTarget conference this week that his company plans to migrate at least 80% of its more than 300,000 employees to voice over IP by 2008. The project will replace approximately 900 PBXs around the world with regional IP installations. IBM's server-based IP telephony platform is going to run on Linux."
Why dont we hear about the dozens of new products that are running Tron daily? Why is linux always big news here?
:-)
Hey linux is running some server some place! WHAT A BREAK THROUGH!
Wake me when BeOS is running something, that will be news
The physical line is called a DS1. A DS1 is 24 B channels (Each B channel is 64k/sec of bandwidth)
A DS0 is one channel (ISDN has one or two of these), a DS1 is 24, and a DS3 is 720 B's (I think, a DS3 is 30 DS1's)
So, a DS1 is the line. When you use all those B channels as one data line, the DS1 is called a T1. But a T1 is not the only option.
You can also keep those 24 channels seperate, and in this case the DS1 is called a PRI. With this setup, you generally turn up one or more of these 24 channels each as its own phoneline, so you can get 24 phonelines.
Due to switching, this isnt exactly acurate. You either set the PRI to have 24 channels of 56k each, or 23 channels of 64k. The extra space is used for signaling. If you are doing voice, or analog dialup for an isp, you can go with 24 chanels of 56k
I hate to say this, but on almost all of your points, you are wrong.
A T1 is the physical line (L1 is the OSI model)
on T1 rides DS1 signal. These the 24 64k channels. That is the DS1, though most people using T1 and DS1 interchangably, a DS1 can ride on a variety of media.
You can, using a channel bank use these 24 channels as phone lines. The phone lines will (generally) have no more services avalable than your standard POTS line. A raw DS1 is usually used to provide a dedicated connection to the long distance carrier, to bypass the CLEC/ILEC and give you better LD rates.
A PRI, an ISDN specification, can be thought of as an application that can run on a DS1. A PRI, at least none that I have heard of, robs ANY k from a the B channel, one or more channels are allocated to the D channel, the rest are B channels.