3Com 10014299 Network Router User Manual


 
134 CHAPTER 10: CONFIGURING WAN INTERFACE
Table 132 Set the line code format on the CE1/PRI interface
By default, the line code format on the CE1/PRI interface is hdb3.
6 Set line clock
When the CE1/PRI interface operates as DCE, you should choose the internal
clock, that is, master clock mode. When it operates as DTE, you should choose
the line clock, that is, slave clock mode.
When the CE1/PRI interfaces on two routers are directly connected, the two ends
will respectively operate in line clock mode (slave) and internal clock mode
(master). When the CE1/PRI interfaces on routers are connected to a switch, the
switch will operate as DCE which provides clock signal, the interfaces on the
routers will operate in line clock mode (slave).
Perform the following configurations in CE1/PRI interface view.
Table 133 Set the line clock of the CE1/PRI interface
By default, the line clock of CE1/PRI interface is slave clock.
7 Set the frame format of interface
When the CE1/PRI interface operates in CE1/PRI mode, it supports two types of
frame formats: crc and no-crc4. The frame format crc4 supports the 4-bit Cyclic
Redundancy Check (CRC) on physical frames, whereas the frame format no-crc4
does not.
Perform the following configurations in CE1/PRI interface view.
Table 134 Set the frame format of CE1/PRI interface
By default, the frame format of CE1/PRI interface is no-crc4.
8 Enable/disable internal loopback/external loopback
The interface needs to be set to internal loopback or external loopback when
during the test on some special functions.
Perform the following configurations in CE1/PRI interface view.
Table 135 Enable/disable the internal loopback/external loopback
Operation Command
Set the line code format on the CE1/PRI interface code { ami | hdb3 }
Restore the line code format on the CE1/PRI
interface
undo code
Operation Command
Set the line clock of the CE1/PRI interface clock { master | slave }
Restore the line clock of the CE1/PRI interface
to the default vale
undo clock
Operation Command
Set the frame format of CE1/PRI interface frame-format { crc4 | no-crc4 }
Restore the frame format of CE1/PRI interface undo frame-format
Operation Command
Enable the internal loopback/external loopback of
the CE1/PRI
loopback
Disable the internal loopback/external loopback of
the CE1/PRI
undo loopback