T1 Card for data on Cisco 3945 and Cisco 7206

Question:

I am working on a case where WS-C3750X-12S-S Price T1 card is required for Cisco 3945 and Cisco 7206 Router.

For Cisco 3945 we have variety of cards available i.e.

HWIC-4T      (Clear channel)

HWIC-1CE1T1-PRI (Channelized T1\E1)

Which one should i go for and what is the difference between clear channel and channelized ports

 

For Cisco 7206

PA-MC-8TE1+ , seems only this one is available.

Would requuire your inputs on the same.

Answer:

The problem that I find with the HWIC-4T is that this is not a real T1 card. Its synchronous maximum speed is 8 Mbps and you will need an external DSU, which will provide clocking and determine the speed of the link. On the other hand, HWIC-1CE1T1-PRI is basically an ISDN PRI card but it can be also used as a T1/E1 card for data. Check this configuration guide and look for the options you have with this card:

http://www.cisco.com/en/US/docs/ios/12_4/12_4x/12_4_11xw/fmt1e1ic.html

PA-MC-8TE1 is also a versatile card that has T1/E1 functions so you will need to use the "card type" command to determine if the card would be a T1 or an E1.

http://www.cisco.com/en/US/docs/interfaces_modules/port_adapters/install_upgrade/multichannel_serial/8-port_multichannel_t1.ei_8pri_install_config/2738cfg.html

The configuration for both cards to get a T1 circuit is pretty similar because you need to configure "card type", controllers and their respective channel-groups and timeslots to get the proper number of DS0s to obtain a T1 (For a full T1 is always timeslots 1-24). Moreover, avoid using "network-clock-participate" and "network-clock-select" commands for they are voice/ISDN commands that could trigger clocking issues in a normal data circuit. The clock source command is important and is configured under the controller T1. When the Telco provides clocking in the middle, you can keep "clock source line" on both ends but if the circuit is back-to-back, it is recommended to use "clock source line" in router A and "clock source internal" in router B. In summary, I think the cirucit will come up if you use PA-MC-8TE1/HWIC-1CE1T1-PRI in the circuit as long as you use the proper clocking, timeslots, WS-C3750X-12S-S  framing and line coding for a T1.