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ISDN a packet-swtiching network?
- Thread starter sheila11
- Start date
Sheila,
An AT&T installer once told me that ISDN really stands for "I Simply Don't kNow"
I tend to agree.
Sorry I couldn't be more help, but I simply don't know...
Regards,
Howard Dingman
Pro-Tel Communications
Endicott, NY 13760
mailto:hdingman@holocom.com
An AT&T installer once told me that ISDN really stands for "I Simply Don't kNow"
I tend to agree.
Sorry I couldn't be more help, but I simply don't know...
Regards,
Howard Dingman
Pro-Tel Communications
Endicott, NY 13760
mailto:hdingman@holocom.com
Cheeseontoast
Technical User
ISDN as i have it is a circuit switched transport medium capable of carrying packet switched data. This transport medium does not perform any packet switching and sits lower down the OSI model than the packet switched services it carries.
What you're using ISDN for kind of dictates whether or not it's going to be considered packet switched... in other words, if you're throwing data packets down it, well...
D channel Data is still connection oriented, which means that though it's based on specific protocols and the data contained in it can be used for a variety of things, there's nothing virtual about it's connection. Both ends need to be up and communicating in order for anything to happen... otherwise you've got a useless carrier.
Comes in two flavors, PRI which always uses a T1 for carrier, or BRI which is a little more rare, especially these days. As far as BRI is concerned, ISDN stands for "It still does nothing". People subscribed BRI ISDN for data transport, bonding B channels and allowing for (a) multiple devices to be connected or (b) a faster than modem digital connection. (The Nortel Norstar Key System had a BRI card for voice, but a lot of people in the real world didn't use them for long because reliability was a factor.) T1 carriers being cheap eliminated the popularity for the multiple voice lines and DSL was a cheaper way of getting bits around. So not to answer a question with a question, but what is it that you're trying to do with it?
D channel Data is still connection oriented, which means that though it's based on specific protocols and the data contained in it can be used for a variety of things, there's nothing virtual about it's connection. Both ends need to be up and communicating in order for anything to happen... otherwise you've got a useless carrier.
Comes in two flavors, PRI which always uses a T1 for carrier, or BRI which is a little more rare, especially these days. As far as BRI is concerned, ISDN stands for "It still does nothing". People subscribed BRI ISDN for data transport, bonding B channels and allowing for (a) multiple devices to be connected or (b) a faster than modem digital connection. (The Nortel Norstar Key System had a BRI card for voice, but a lot of people in the real world didn't use them for long because reliability was a factor.) T1 carriers being cheap eliminated the popularity for the multiple voice lines and DSL was a cheaper way of getting bits around. So not to answer a question with a question, but what is it that you're trying to do with it?
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