CCNP课程详解-1-1-EIGRP介绍 (1).pptVIP

Introducing EIGRPEnhanced Interior Gateway Routing Protocol Flexible network designMulticast and unicast instead of broadcast addressManual summarization at any point 100% loop-free classless routingEasy configuration for WANs and LANsLoad balancing across equal- and unequal-cost pathwaysAdvanced distance vectorFast convergenceSupport for VLSM and discontiguous subnetsPartial updatesSupport for multiple network-layer protocolsEIGRP Features EIGRP IP Routing Table Example: EIGRP TablesRouter C Tables: EIGRP PacketsHello: Establish neighbor relationships.Update: Send routing updates.Query: Ask neighbors about routing information.Reply: Respond to query about routing information.ACK: Acknowledge a reliable packet. Initial Route Discovery EIGRP Hello TimersHellos sent once every 5 seconds on the following links:Broadcast media: Ethernet, Token Ring, Fiber Distributed Data Interface (FDDI)Point-to-point serial links: Point-to-point Protocol (PPP), High-Level Data Link Control (HDLC) Point-to-point Subinterface: Frame Relay’s Point-to-Point Subinterface,ISDN BRIHellos sent once every 60 seconds on the following links:Multipoint circuits with bandwidth less than or equal to T1: Frame Relay’s Physical, Frame Relay’s Multi-Point Subinterface, ATM, and X.25Hold time by default is three times the hello time EIGRP MetricSame metric components as IGRP:(K1) Bandwidth(K2) Loading(K3) Delay(K4) Reliability(K5) MTUEIGRP metric is IGRP metric multiplied by 256. EIGRP Metric CalculationBy default, EIGRP metric:Metric = bandwidth (slowest link) + delay (sum of delays)Delay = sum of the delays in the path, in tens of microseconds, multiplied by 256Bandwidth = [107 / (minimum bandwidth link along the path, in kilobits per second)] * 256Formula with default K values (K1 = 1, K2 = 0, K3 = 1, K4 = 0, K5 = 0):Metric = [K1 * BW + ((K2 * BW) / (256 – load)) + K3 * delay]If K5 not equal to 0:Metric = metric * [K5 / (reliability + K4)]: A ? B ? C ? D Least bandwidth 64 kbp