Integrated IS-IS NBMA Design Solutions
Designing IS-IS networks across NBMA WANs is not as straightforward as designing other protocols, such as EIGRP, because IS-IS does not explicitly support NBMA. On the other hand, IS-IS over NBMA is not as complicated as OSPF either. In the good old days, most organizations had a broadcast network (such as Ethernet) for the LAN and point-to-point links (such as serial links) for the WAN. Accommodating these different technologies when building a routing protocol made ..
OSPF has five types of packets used for various reasons. Table 8-1 documents the different OSPF packet types and describes their functionality. Table 8-1. OSPF Packet Types Type Description Functionality 1 Hello To discover neighbors and form DR/BDR relationship and exchange neighbor capabilities. 2 Database description To elect master/slave for the database exchange process and to exchange the LSA ..
The current IEEE 802.11e draft describes an Enhanced Distributed Coordination Function (EDCF). EDCF is an enhancement of DCF, previously described. The main enhancement is the adjustment of variable CWmin and CWmax random backoff values based upon traffic classification. This feature is supported in current Cisco Aironet software. Figure 11-6 shows the principle behind different CWmin values per traffic classification. All traffic waits the same DIFS, but the CWmin value use..
You can use the ntp access-group command to restrict which devices you want your router to allow NTP associations with: Router#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#access-list 88 permit host 172.25.1.1 Router(config)#access-list 88 permit host 10.1.1.1 Router(config)#access-list 99 permit 172.25.0.0 0.0.255.255 Router(config)#access-list 99 permit 10.2.0.0 0.0.255.255 Router(config)#clock timezone EST -5 Router(..
Redistributing Routes with BGP
When connecting two or more IGPs using BGP, you sometimes need to configure redistribution between the IGP and BGP on both routers. To make the example more interesting, we will assume that we need to connect an EIGRP network to an OSPF network using a pair of BGP routers. The first router redistributes routes from BGP into OSPF: Router1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router1(config)#router ospf 100 Router1(config-rout..
