Internal BGP Neighbors

A BGP router considers each neighbor to be either an internal BGP (iBGP) peer or an external BGP (eBGP) peer. Each BGP router resides in a single AS, so neighbor relationships are either with other routers in the same AS (iBGP neighbors) or with routers in other autonomous systems (eBGP neighbors). The two types of neighbors differ only slightly in regard to forming neighbor relationships, with more significant differences in how the type of neighbor (iBGP or eBGP) impacts th..

Acting as a DHCP Client

Setting an IOS device to be a DHCP client is easy. The command is supplied in interface configuration mode. Instead of supplying an IP and mask, the IP address command is used to specify DHCP:  Router(config)#interface fastethernet0/0  Router(config-if)#ip address dhcp  This is a quick and painless way to get remote offices and SOHO users up and running 

Sophisticated Metric

EIGRP uses a sophisticated metric that considers bandwidth, load, reliability, and delay. That metric is Although this equation looks intimidating, a little work will help you understand the math and the impact the metric has on route selection.  You first need to understand that EIGRP selects path based on the fastest path. To do that it uses K-values to balance bandwidth and delay. The K-values are constants that are used to adjust the relative contribution of t..

Provider-Edge QoS Considerations

PE designs are relevant for service providers (and for enterprises that are self-managing their own MPLS VPNs). Two unique considerations for PE QoS design are discussed next: •    Service provider-to-enterprise models •    MPLS DiffServ tunneling modes These considerations are examined in more detail in the following sections. Service Provider-to-Enterprise Models The PE edges facing customer CEs are complementary to the enterprise-to-se..

Cisco Implementations of Frame Relay Fragmentation

This section discusses the few fragmentation schemes supported by Cisco. Cisco has developed three different methods of performing fragmentation with Frame Relay: FRF.12 Fragmentation, Frame Relay Fragmentation using FRF.11 Annex C, and the Cisco Proprietary Fragmentation. Each fragmentation scheme uses a different data format or encapsulation. Frame Relay frames are fragmented based on one of the three formats, depending on how the Frame Relay PVC was set up. It is importan..