3Com 10014299 manual Circular DCC, Dcc

706CHAPTER 51: CONFIGURING DCC

DCC Configuration 3Com routers provide two DCC configuration methods: circular DCC, and Methods resource-shared DCC. With distinguishing features, these two methods are

applicable to different applications. In applications, the participating parties of a call can flexibly select either method as needed. In other words, one party can adopt circular DCC while the other party adopt resource-shared DCC to originate a call.

Circular DCC

Circular DCC has the following features:

■A logical dial (dialer) interface can use the services provided by multiple physical interfaces (such as Serial0). However, a physical interface can only belong to one dialer interface. That is, a physical interface can only provide one type of dial service.

■The user can either bind a physical interface to a dialer interface for inheriting the DCC parameters by assigning it to a dialer circular group, or directly configure DCC parameters on the physical interface.

■All the physical interfaces served for the same dialer circular group inherit the attributes of the same dialer interface.

■Through configuring the dialer route command, a dialer interface can be associated with multiple dialing destination addresses. Through configuring the dialer number command, however, a dialer can only be associated with one dialing destination address.

In addition, all the B channels on an ISDN BRI interface inherit the configuration of this physical interface, and the dial route will become more complicated as the network grows and more protocols are supported. Therefore, the application of circular DCC is restricted due to the static binding between the dialing destination addresses and the physical interface configuration.

Association between the physical interfaces and dialer interfaces in circular DCC

Figure 224 Association between the physical interfaces and dialer interfaces in Circular

DCC

PhysicalDialer

interfaces interfaces

Serial0

dialer number

Destination A

Bri1

Dialer1

Serial1

Bri0 Dialer2

dialer route

Destination B

Serial2

Async0

dialer route

Destination C

As shown in Figure 224, in the case that dialer interfaces are used, a physical interface can only belong to one dialer interface, but each dialer interface can