Notes:

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• Network Layer packet Interface Port .

• Packet route path . route path ( ) best route best path . r1 r2 route best path 2,5,6 .
  • 1, 3, 6
  • 1, 4, 7
  • 2, 5, 6
  • 2, 5, 7

• Packet routing .

• (router) routing H/W routing S/W . , , X.25 , ATM Switch .

• routing . (Routing Information) , . Protoco Routing Information Exchange Protocol Routing Protocol . Application Layer .

• routed protocol encapsulation protocol IP, IPX, Appletalk . routing protocol IP packet, IPX packet, Appletalk packet , protocol . IP routing protocol RIP, IGRP, OSPF, BGP , IPX Novell RIP, NLSP , Appletalk RTMP .

Notes:

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• packet Address .

• Address Network Address Node Address .

• LAN Network Address Node Address .

• LAN LAN WAN link LAN Network Address , Node Address 2 .

• IP, IPX, Appletalk Address Address Network Address Node Address .
  • IP Address : 32bit . Network Address Node Address
  • IPX Address : 80bit . Network Address 32bit, Node Address 48bit
  • Appletalk Address : 24bit . Network Address 16bit, Node Address 8bit

• IP, IPX, Appletalk Routing Protocol Network Address . Network-Level Routing

• PSTN, X.25, Frame Relay, ATM Network Address Node Address routing point-to-point(end-to-end) routing

Notes:

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• Bandwidth : 1.5Mbps link 45Mbps link .

• Delay : cable 1.5Mbps link delay 200msec 45Mbps link delay 500msec . ?

• Reliability : link .

• Load : .

• MTU : MTU .

• Hop Count : 1 hop . hop count .

• money : link .

• IP Routing Protocol
  • RIP : hop count
  • IGRP : Bandwidth, Delay, Reliability, Load, MTU
  • OSPF : Bandwidth

Notes:

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• Static Route . Static Route Dynamic Routing Protocol Dynamic Routing Protocol . Static Route .

• Dynamic Route Dynamic Routing Protocol . .

• Interior Gateway Protocol
  • IP Routing Protocol RIP, IGRP, EIGRP, OSPF .

• Exterior Gateway Protocol
  • IP Routing Protocol BGP .

• Singlepath Routing Protocol <-> Multipath Routing Protocol
  • a cost 100, b cost 50 b best path b . traffic a b . singlepath routing protocol , multipath routing protocol .
  • singlepath : RIP, OSPF, BGP
  • multipath : IGRP, EIGRP
  • cost multipath .

• OSPF Routing Information . RIP .
  • Flat : RIP, IGRP, EIGRP, BGP
  • Hierarchical : OSPF

Notes:

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• Distance Vector Routing Protocol
  • : Routing Loop : convergence time .
  • : Counting to Infinity : routing loop distance (cost)
  • : distance (RIP 16)
  • : Split Horizon :
  • : Route Poisoning : Down distance
  • : Hold-Down Timers : Down

• Distance Vector Routing Protocol : RIP, IGRP, EIGRP*

• Link State Routing Protocol
  • : unsynchronized update
  • : inital flooding link CPU
  • : time stamp, counter
  • : . Link State , ,

• Link State Routing Protocol : OSPF

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