Ericsson LBI-39224 manual Desired

LBI-39224

Figure 14 Audio Interface Type Dialog Box

(Audio Board selected)

T1/E1 Interface option

If T1/E1 Interface Card was selected (Figure 15), a new set of option buttons will appear.

T1 is a digital transmission facility operating at 1.544 Mbps (million bits per second) in a full-duplex, time-division-multiplexing mode. T1 is the first level or primary rate within a digital transmission and switching hierarchy defined by AT&T called a T Carrier System. North America has adopted the T Carrier System as a standard for digital transmission of voice, data, and images. Time-division multiplexing permits the derivation of logical channels within the serial bit stream. The CEC/IMC T1/E1 Interface will allocate twenty-four 64 kbps T1 channels.

E1 digital transmission is very similar to T1. The major difference is in the bit rate. E1 is a digital transmission facility operating at 2.048 Mbps. The difference in bit rate allows for different channel allocation schemes. The CEC/IMC T1/E1 Interface will allocate thirty-one 64 kbps E1 channels. E1 transmission has been adopted as the digital transmission standard in European countries.

T1/E1 selection is performed at the CEC/IMC Manager on a CEC/IMC wide basis. Changing the line type will cause the entire T1/E1 database to be reset (lost) for all T1/E1 "sites." T1 or E1 selection is dependent upon the line service coming into the CEC/IMC (T1 and E1 lines are physically different), and as mentioned above, depends upon what part of the world you are in. Selecting T1 or E1 should only be required when the system is first configured, after that the current system configuration will be indicated when the Audio Interface Type dialog box appears on your screen and changing line type is not necessary or

desired. Choose the OK button and the

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