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You &nbsp;need to have an IP address for the T1 interface<br />
You need to know the encapsulation (PPP | Frame-relay | HDLC)<br />
Is this an Internet connection? You need default gateway<br />
Do you have a firewall behind the router, or is this your security router/firewall?<br />
Do you have the internal WIC-T1-DSU module, or are you using an external CSU/DSU?<br />
<br />
Basic config example<br />
&nbsp; interface serial 0/0<br />
&nbsp; &nbsp; ip address a.b.c.d 255.255.255.248<br />
&nbsp; &nbsp; no shutdown<br />
<br />
Verify:<br />
&nbsp;sho interface serial 0/0<br />
Look for indications : line is UP | DOWN &nbsp; protocol is UP | DOWN<br />
Looking for UP | UP <br />

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You  need to have an IP address for the T1 interface
You need to know the encapsulation (PPP | Frame-relay | HDLC)
Is this an Internet connection? You need default gateway
Do you have a firewall behind the router, or is this your security router/firewall?
Do you have the internal WIC-T1-DSU module, or are you using an external CSU/DSU?

Basic config example
  interface serial 0/0
    ip address a.b.c.d 255.255.255.248
    no shutdown

Verify:
 sho interface serial 0/0
Look for indications : line is UP | DOWN   protocol is UP | DOWN
Looking for UP | UP


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I have a new T-1 line and Cisco 1721 router. &nbsp;I would like to configure the router with the new T-1. Where do I start?
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I have a new T-1 line and Cisco 1721 router.  I would like to configure the router with the new T-1. Where do I start?

New User: How do you configure a Cisco 1721 router with a new T-1 line?

The term broadband commonly refers to high-speed Internet access that is always on and faster than the traditional dial-up access. Broadband includes several high-speed transmission technologies such as digital subscriber line (DSL), cable, fiber optics, wireless (for which there is a separate topic), satellite and broadband over powerlines (BPL).