BGP uses four basic messages. Table 12-4 lists the message types and provides a brief description of each. Table 12-4 BGP Message Types
Multicast Addressing for Updates
EIGRP uses both multicast and unicast addressing. Some packets are sent reliably using Real-Time Protocol (RTP), a Cisco proprietary protocol that oversees the communication of EIGRP packets. These packets are sent with sequence numbers to make the transmission of data reliable. Hellos and ACKs do not require acknowledgement. Incremental updates cannot be anticipated; therefore, update, query, and reply packets must be acknowledged by the receiving neighbor.&nbs..
The 802.6 DQDB standard never became popular as a means to interconnect LAN or digital telephony systems. Within the US, DQDB made a brief appearance as a commercial service in the form of the Switched Multimegabit Data Service (SMDS). However, in terms of tariff or capabilities, it never held any real advantage over Frame Relay, and had only marginal advantage over T1. Moreover, in many ways MANs are based upon the assumption that customers want to connect LANs at Layer 2. A..
A campus network’s core layer provides connectivity of all distribution-layer devices. The core, sometimes referred to as the backbone, must be capable of switching traffic as efficiently as possible. Core devices, sometimes called campus backbone switches, should have the following attributes: ■ Very high throughput at Layer 3 ■ No costly or unnecessary packet manipulations (access lists, packet filtering) ■ Redundancy and resilience for high availability ■ Advanc..
To enable MD5-based EIGRP packet authentication, you must first define a key chain for the encryption, and then apply the authentication commands to the interface as follows: Router1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router1(config)#key chain ORA Router1(config-keychain)#key 1 Router1(config-keychain-key)#key-string oreilly Router1(config-keychain-key)#exit Router1(config-keychain)#exit Router1(config)#interface Ser..
