Cisco IOS Wide-Area Networking Configuration Guide - Free Books

X.25 Configuration Task ListConfiguring X.25 and LAPBBoth priority and custom queueing can be defined, but only one can be assigned to a given interface. Toconfigure priority and custom queueing for LAPB, perform these tasks in the following order:1. Perform standard priority and custom queueing tasks except the task of assigning a priority orcustom group to the interface, as described in the chapters“Configuring Prioirity Queueing” and“Configuring Custom Queueing” in the Cisco IOS Quality of Service Solutions ConfigurationGuide.2. Perform standard LAPB encapsulation tasks, as specified in the section “Configuring a LAPBDatagram Transport” earlier in this chapter.3. Assign either a priority group or a custom queue to the interface,as described in the chapters“Configuring Prioirity Queueing” and “Configuring Custom Queueing” in the Cisco IOS Quality ofService Solutions Configuration Guide.4. The lapb hold-queue command is no longer supported, but the same functionality is provided bythe standard queue control command hold-queue size out.Configuring Transparent Bridging over Multiprotocol LAPBTo configure transparent bridging over multiprotocol LAPB, use the following commands beginning inglobal configuration mode:CommandPurposeStep 1 Router(config)# interface serial number Enters interface configuration mode.Step 2 Router(config-if)# no ip address Assigns no IP address to the interface.Step 3 Router(config-if)# encapsulation lapb multi Configures multiprotocol LAPB encapsulation.Step 4 Router(config-if)# bridge-group bridge-group Assigns the interface to a bridge group.Step 5 Router(config)# bridge bridge-group protocol {ieee | dec} Defines the type of Spanning-Tree Protocol.NoteYou must use the encapsulation lapb multi command rather than the encapsulation lapb protocolbridge command to configure transparent bridging over multiprotocol LAPB.For an example of configuring transparent bridging over multiprotocol LAPB, see the section“Transparent Bridging for Multiprotocol LAPB Encapsulation Example” later in this chapter.X.25 Configuration Task ListTo configure X.25, complete the tasks in the following sections. The interface, datagram transport, androuting tasks are divided into sections based on how common the feature is and how often it is used.Those features and parameters that are less common are found in the sections “Configuring AdditionalX.25 Interface Parameters,” “Configuring Additional X.25 Datagram Transport Features,” and“Configuring Additional X.25 Routing Features.” LAPB frame parameters can be modified to optimizeX.25 operation, as described earlier in this chapter. All these features can coexist on an X.25 interface.• Configuring an X.25 Interface (Required)• Configuring Additional X.25 Interface Parameters (Optional)6