DSCP Settings and Terminology

Several DiffServ RFCs suggest a set of values to use in the DSCP field and an implied meaning for those settings. For instance, RFC 2598 defines a DSCP of decimal 46, with a name Expedited Forwarding (EF). According to that RFC, packets marked as EF should be given queuing preference so that they experience minimal latency, but the packets should be policed to prevent them from taking over a link and preventing any other types of traffic from exiting an interface during perio..

Configuring OSPF with the Broadcast Network Type

With the broadcast OSPF network type, neighbors are automatically discovered and the hello timer is faster than with NBMA. Configuring a broadcast interface just involves changing the OSPF network type—no neighbor statements are required.  The broadcast OSPF network type works best with a fully meshed network. Example 6-3 shows a typical configuration of the broadcast OPSF network type.  Example 6-3. Configuring a Broadcast Network

Distributed Queue Dual Bus

The standard resulting from this IEEE study is numbered 802.6, and named Distributed Queue Dual Bus (DQDB), which essentially describes both the topology used by the technology, and the media access mechanism. In this technology, illustrated by Figure 3-10, two optical fiber buses carry communications between all stations. The buses are unidirectional, and a DQDB station needs to attach to both, either through a passive or active fiber tap. One bus communicates with upstream ..

Using STUN

STUN provides the ability to emulate an SDLC circuit through an IP network. To simply connect two SDLC or two HDLC ports on different routers, you can use the following: Stun-A#configure terminal Enter configuration commands, one per line.  End with CNTL/Z. Stun-A(config)#interface Loopback0 Stun-A(config-if)#ip address 10.1.15.5 255.255.255.252 Stun-A(config-if)#exit Stun-A(config)#stun peer-name 10.1.15.5 Stun-A(config)#stun protocol-group 1 basic Stun-A(config)#inter..

Using HSRP for Home Agent Redundancy

For this recipe, we must configure two nearly identical Home Agent routers. Here is the configuration of the first one: RouterHome1#configure terminal Enter configuration commands, one per line.  End with CNTL/Z. RouterHome1(config)#interface FastEthernet0/0 RouterHome1(config-if)#ip address 192.168.9.2 255.255.255.0 RouterHome1(config-if)#standby 1 ip 192.168.9.1 RouterHome1(config-if)#standby 1 name HA-GROUP RouterHome1(config-if)#exit RouterHome1(config)#route..