Central Office & CID Question 2

[lvNortel]

I have always wondered why hte CO's only send the CID information after the first ring. This causes customers to have to wait for the information before answering unlike a PRI.

Why does or must the CO send CID info. between rings 1 and 2 on POTS lines?

Also, I find that the 15 characters allowed just is not enough for most business names, also, ,.><()?/ & * .com .net etc. are not allowed.

Maybe when CID was first invented they did realized these things would be needed or maybe the speed at which the data is sent is to slow?

Any ideas?

"A phone is a phone and not a computer workstation".

 

[mforrence]

If CID were sent before the first ring, most key systems wouldn't be "listening". First ring notifies system to "wake up and listen" by tripping the ring sensor.
No special characters is to allow the most varied use of the CID name. Many applications and operating systems use special characters for other uses - hence including them with CID could present a potential conflict.
In the end, CID takes a lowest common denominator approach in order to be useful to the widest variety of users.
There is no doubt that PRI and SIP bring a host of additional signaling possibilities to the table and can make this type of technology sing.

 

[LkEErie]

You might look at the history of CID and the equipment available at the time it was developed. My very first "Micromodem" for the Apple II computer was acquired in 1980, a magnificent 300 baud modem.

CID was invented 10 years earlier. How do you propose the data be sent? BEFORE the phone rings? Not likely. ANI is sent AFTER the call is answered. Not practical for screening calls, so I guess after the first ring is the only method to send data cheaply.

Here's a link to the history of the development of CID. Check out the patents, quite a few.

http://en.wikipedia.org/wiki/Caller_ID

LkEErie

 

[lvNortel]

Send it at the time the phone rings and speed up the baud rate. Also, I have seen some systems even little key systems that have a little feature that will allow the button for the line to start blinking or light up but will not activate the ringer until the CID information has been captured or a set number of ms has passed in the event the CID info has not been sent. This way this ensures that the user does not answer the phone before the CID has been received.

When the handset starts ringing the CID is already there waiting for them. This is a good work around for the dealy caused by the CO. Nortel does not have this feature. The users has to wait for the display.

"A phone is a phone and not a computer workstation".

 

[LkEErie]

Was that a question, a solution, or an argument? Sure, how about we put PRI trunks in all residential lines, or a key system like gizmo in every place that needs CID?

Some CID boxes suppress the first ring and/or process the CID number, so it's not impossible. Our lady in the Nortel/Aastra box is busy reciting the CID number between the first and second rings, but we paid over $100 wholesale for the phone back in 1990's money. The Lowest Common Denominator is exactly what we have 110 baud (or is it 300?) transmitted in the SILENT period after the first ring. (the ring harmonics preclude doing it during the ring)

LkEErie

 

[jknichols]

If my reaserch is right it is actually 1200 Baud (or about 120 characters per second). A number only transmission would have 10 characters for the number, 8 characters for the data and time (MMDDhhmm) plust start and checksum giving 20 characters or 1/6 of a second. Adding another 20 characters for name would still only be 1/3 of a second, so IMHO, breaking the standard by upping the baud rate would not yield a noticible change.

 

[lvNortel]

How about adding some more space so the Business Name can be longer. 15 with the spaces just does not do it for most of the CID Names I see. They get chopped off at the end. I think it should be 30 Chrs.

"A phone is a phone and not a computer workstation".

 

[telcodog]

Your arguements are moot! Nobody is going to change anything regarding legacy analog trunks as all phone companies are phasing that stuff out in favour of SIP......so don't hold your breath waiting.