Ce1/Pri Interface Features Supported By The Ar1200 - Huawei AR1200 series Configuration Manual

Huawei AR1200 Series Enterprise Routers
Configuration Guide - Interface Management

6.2 CE1/PRI Interface Features Supported by the AR1200

This section describes physical attributes of CE1/PRI interfaces supported by the AR1200.
CE1/PRI interfaces are provided by the 1E1T1-M/2E1T1-M interface card of the AR1200. A
1E1T1-M/2E1T1-M interface card can provide CE1/PRI interfaces or CT1/PRI interfaces,
depending on the working mode.
Physical Attributes of a CE1/PRI Interface
A CE1/PRI interface can be configured with different physical attributes when working in
different modes:
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Clock Mode
To exchange data correctly, communicating parties must have their clocks synchronized.
A CE1/PRI interface works in either of the two clock modes:
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Generally, the interface at one end of a link works in master clock mode, and the interface at the
other end works in slave clock mode.
Frame Format
A CE1/PRI interface supports two frame formats:
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Line Idle Code
The line idle code is the code sent over a timeslot that is not not bundled to form a channel.
The AR1200 supports two line idle codes: 0x7e and 0xff.
Issue 01 (2012-04-20)
interface and supports link layer protocols such as PPP and network protocols such as
IP, and can be configured with Dialer Control Center (DCC) parameters.
E1 mode: A CE1/PRI interface can be configured with the clock mode, line idle code,
interframe filling tag, and alarm indication signal (AIS) detection.
CE1/PRI mode: A CE1/PRI interface can be configured with the clock mode, frame format,
line idle code, interframe filling tag and remote alarm indication (RAI) detection.
In master clock mode, the CE1/PRI interface uses internal clock signals.
In slave clock mode, the CE1/PRI interface uses line clock signals provided by the interface
acting as master.
Cyclic redundancy check 4 (CRC4) multiframe format: A CRC4 multiframe is formed by
the first bit in each frame transmitted over timeslot 0. This format contains 16 consecutive
pulse code modulation (PCM) frames.
Basic frame format (non-CRC4): This format is also called the dual-frame format or odd-
even frame format. An even frame in timeslot 0 transmits frame alignment signal 0011011.
An odd frame in timeslot 0 has a fixed value 1 in the second bit, which distinguishes it from
an even frame with value 0 in the second bit.
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