3Com Router User Manual

CE3 Interface147
Ta b l e 164   Enter the view of the specified E3 interface
2Set Clock Mode of CE3 Interface
Perform the following configuration in CE3 interface view.
Ta b l e 165   Set clock mode of the CE3 interface
By default, CE3 interface uses slave clock.
The user can also set clock mode for E1 channels of CE3 interface.
Ta b l e 166   Set clock mode of the E1 channel
By default, E1 channel uses slave clock.
3Set National Bit for CE3 Interface
Perform the following configuration in CE3 interface...

148CHAPTER 10: CONFIGURING WAN INTERFACE
If framing has been enabled on an E1 channel, you can set its frame format. 
Perform the following configuration in CE3 interface view.
Ta b l e 170   Set E1 frame format
By default, the frame format of E1 channel is no-crc4.
6Configure Operating Mode of CE3 Interface
When setting the operating mode of an CE3 interface, you should set the 
operating modes of both the CE3 interface and the E1 channels on the interface.
Perform the following configuration in CE3...

CT3 Interface149
Display and Debug CE3 
InterfaceThe display and debug operations of CE3 interface include disabling interface and 
displaying interface information. But you should be careful when using the 
shutdown command, because disabling an interface will cause the interface to 
stop working.
Perform the following configuration in all views.
Ta b l e 173   Display and debug CE3 interface
The enabling/disabling operation done on the CE3 interface takes effect on CE3 
interface, the demultiplexed E1...

150CHAPTER 10: CONFIGURING WAN INTERFACE
■Set CRC of the Serial Interface
Depending on the networking requirements, the user perhaps needs to configure 
the parameters such as PPP, Frame Relay and IP address for the CT3 interface. For 
details, refer to the involving chapters.
1Enter the view of the specified CT3 interface
CT interface uses the controller command to enter its view.
Perform the following configuration in system view. 
Ta b l e 174   Enter specified CT3 interface view
2Set Clock Mode
CT3...

CT3 Interface151
Ta b l e 178   Set loopback mode of the CT3 interface 
Difference between two types of external loopback of the CT3 interface: Frame 
header overhead should be processed for external payload loopback (payload) 
while frame is not processed for external remote loopback (remote). 
By default, loopback is disabled.
Single-channel loopback can be set on the T1 channels on a CT3 interface, and 
the settings of individual channels are independent.
Ta b l e 179   Set loopback mode of T1...

152CHAPTER 10: CONFIGURING WAN INTERFACE
By default, CT3 mode is used. 
When CT3 interface works in T3 mode, the system will automatically create a 
serial interface whose number is serial number/0:0 and whose rate is 
44.736Mbps. The interface has the same logic feature as that of a synchronous 
serial interface; therefore, it can be regarded as a synchronous serial interface for 
further configuration.
Ta b l e 183   Set the operating mode of T1 channel
The operation mode of T1 channels defaults to CT1...

CT3 Interface153
Ta b l e 185   Disable and Enable CT3 interface
The enabling/disabling operation done on the CT3 interface takes effect on CT3 
interface, the T1 channels and the serial interfaces formed through binding 
operation. The enabling/disabling operation done on the T1 interface takes effect 
on T1 interface and the serial interfaces formed through binding operation. 
To disable/enable only the serial interface formed by T3, the serial interface formed 
by T1 channel or the serial interface...

154CHAPTER 10: CONFIGURING WAN INTERFACE 

11
CONFIGURING LOGICAL INTERFACE
This chapter contains information on the following topics:
■Logical Interface Introduction
■Dialer Interface
■Loopback Interface
■Null Interface
■Sub-Interface
■Standby Center Logic Channel
■Virtual-Template and Virtual Interface
Logical Interface 
IntroductionThe logical interface refers to the interface that can exchange data, but does not 
exist physically and needs to be established through configuration, including the 
Dialer interface, loopback interface, null...

156CHAPTER 11: CONFIGURING LOGICAL INTERFACE
Some applications (such as configuring local peer of SNA) requires that a local 
interface with specified IP address should be configured without affecting physical 
interface configuration. Furthermore, this address should have a 32-bit mask to 
reduce the use of IP addresses and it should be advertised by the routing 
protocols. Therefore, the loopback interface is added to meet this requirement.
Configure Loopback 
InterfaceLoopback interface configuration...