DDR on synscronous serial interfaces

[kkalaycioglu]

What is use of DDR (dialer in-band etc.) under synchronous serial interfaces? I read about this in the book "CCIE Fundamentals and Case Studies".

Regards.

[oleg_vk]

Hi there,

By this URL you can find more info:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fdial_c/fnsprt5/dcdspoke.htm#1000999

Best regards,

Oleg.

[kkalaycioglu]

So, connecting a sync serial to the ISDN cloud via a TA is the main usage of this kind of config. Is that right?

Regards.

[Kevin Dorrell]

It does seem rather strange, doesn't it. I mean, I am familiar with dialup ISDN, and the older dialup asynchronous modems, but frankly I have never come across a dialup synchronous modem. I suppose they must exist, but where? Maybe in the IBM world.

Kevin Dorrell

Luxembourg

[oleg_vk]

I use this once in my life while ago. It was Cisco 1005, which has 1 Serial and 1 Ethernet. When IOS 12.0 was introduced we did some tricks. Serial was connected to normal async modem and we used "physical layer async" which was turning Serial to async intercase and we can use it as normal dial-up line. Dialer in-band was used on Serial interface.

Regards,

Oleg.