Physical Transports

Depending on the type of service you buy and the speed of the circuit, the local telco will deliver the circuit to your company on either copper or fiber optic cable. Circuits delivered on a copper based cable are referred to as electrical terminations. Circuits delivered on fiber optic based cable are referred to as optical terminations. The distinction becomes important at the DS3 and OC-3 level because both have specifications for electrical or optical interfaces. The termination type you request from your telecommunications provider will depon the interface type you have elected to install in your router.

A T1 circuit is actually made up of 24 DS0 channels. Each of these DS0 channels is usually 64Kbps, which gives ...

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