List of Figures

Chapter 1: Introduction to Internetworking

Figure 1.1: Repeater in a LAN

Figure 1.2: Bridging a LAN

Figure 1.3: LAN connections in a hub

Figure 1.4: A router segmenting a LAN

Figure 1.5: Routers connecting three cities creating a WAN

Figure 1.6: Physical data flow through a model

Figure 1.7: Logical data flow between peer layers

Figure 1.8: The layers of the OSI reference model

Figure 1.9: OSI layer functions

Figure 1.10: Transport layer data segments sharing a traffic stream

Figure 1.11: Establishing a connection-oriented session

Figure 1.12: Transmitting segments with flow control

Figure 1.13: TCP/IP window sizes

Figure 1.14: Transport layer reliable delivery

Figure 1.15: Communicating through an internetwork

Figure 1.16: The Network layer process

Figure 1.17: Ethernet II and 802.3 Ethernet frames

Figure 1.18: The LLC sublayer of the Data Link layer

Figure 1.19: Data encapsulation at each layer of the OSI reference model

Figure 1.20: FDDI network topology

Figure 1.21: Dual-ring reliability

Figure 1.22: Token Ring media access control field

Figure 1.23: Token Ring frame status field

Figure 1.24: Identifying collision and broadcast domains

Chapter 2: LAN Segmentation

Figure 2.1: Ethernet network with repeaters

Figure 2.2: Segmentation with a bridge

Figure 2.3: Routing tables are kept for each Network layer routing protocol.

Figure 2.4: Empty forward/filter table on a switch

Figure 2.5: How switches learn hosts’ locations

Figure 2.6: Broadcast storm

Figure 2.7: Multiple frame copies

Figure 2.8: A traditional 80/20 network

Figure 2.9: A 20/80 network

Figure 2.10: Different switching modes within a frame

Figure 2.11: Flat network structure

Figure 2.12: The advantage of a switched network

Figure 2.13: Physical LANs connected to a router in a traditional network

Figure 2.14: Switches removing the physical boundary

Figure 2.15: Access and trunk links in a switched network

Figure 2.16: Half-duplex circuitry

Figure 2.17: Full-duplex circuitry

Chapter 3: Network Protocols

Figure 3.1: The DOD model and the OSI model

Figure 3.2: The TCP/IP protocol suite

Figure 3.3: MAC addresses

Figure 3.4: Resolving a local IP address

Figure 3.5: Resolving a remote IP address

Figure 3.6: IPX protocol suite and the OSI model

Figure 3.7: Remote IPX clients on a serverless network

Chapter 4: Pre-Design Procedures

Figure 4.1: Cisco’s Small- to Medium-Sized Business Solutions Framework

Figure 4.2: High-level topology map

Chapter 5: Designing Modular Network Topologies

Figure 5.1: A basic hierarchical network

Figure 5.2: An expanded hierarchical network

Figure 5.3: Hierarchical network design

Figure 5.4: Access layer additions

Figure 5.5: A sample internetwork

Figure 5.6: An HSRP example—logical

Figure 5.7: An HSRP example—physical

Figure 5.8: A full mesh network

Figure 5.9: A redundant hierarchical network

Figure 5.10: Pinhole congestion

Chapter 6: Enterprise WAN Design

Figure 6.1: Point-to-point connections between branches and the corporate office

Figure 6.2: Point-to-point protocol stack

Figure 6.3: Partial meshed network examples

Chapter 7: Network Addressing and Naming

Figure 7.1: IP address example

Figure 7.2: The makeup of an IP version 4 address

Figure 7.3: Hierarchical IP address structure

Figure 7.4: Hierarchical routing decisions

Figure 7.5: VLSM subnet adjustment

Figure 7.6: VLSM implementation example

Figure 7.7: Fourteen subnets with no VLSM applied

Figure 7.8: Fourteen subnets with VLSM applied

Figure 7.9: The three steps in creating a VLSM table

Figure 7.10: VLSM network example one

Figure 7.11: VLSM table example one

Figure 7.12: VLSM network example two

Figure 7.13: VLSM table example two

Figure 7.14: VLSM network example three

Figure 7.15: VLSM table example three

Figure 7.16: VLSM network example four

Figure 7.17: VLSM table example four

Figure 7.18: Route summarization

Figure 7.19: Discontiguous networking example

Figure 7.20: An ip unnumbered example

Figure 7.21: An ip helper-address single server example

Figure 7.22: An ip helper-address multiple server example

Figure 7.23: Network address translation

Figure 7.24: Serial interface addressing example

Chapter 8: Routing Protocols

Figure 8.1: Distance-vector operation with three routers.

Figure 8.2: Distance-vector network decisions

Figure 8.3: Route types recognized by IGRP

Figure 8.4: IGRP route update process

Figure 8.5: Split horizon

Figure 8.6: Route updates vs. calculation

Figure 8.7: Best-route selection

Figure 8.8: Handling route changes

Chapter 9: Link-State and Bridging Protocols

Figure 9.1: OSPF peer initialization

Figure 9.2: OSPF LSU and LSAck exchange

Figure 9.3: IS-IS areas with Level 1 and Level 2 routing

Figure 9.4: IS-IS area and NET configuration

Figure 9.5: OSI-model bridge routing

Figure 9.6: Transparent bridge

Figure 9.7: Workstation 1–to–Server 1 frame

Figure 9.8: Server 1–to–Workstation 1 frame

Figure 9.9: Redundant bridges

Figure 9.10: Spanning-Tree Protocol implemented

Chapter 10: Cisco IOS Software

Figure 10.1: Priority assignment using weighted fair queuing

Figure 10.2: Bandwidth allocation with weighted fair queuing

Figure 10.3: Dispatching algorithm in priority queuing

Figure 10.4: Custom queuing algorithm

Chapter 13: Designing Networks for Integrated Security and Voice Transport

Figure 13.1: Firewall placement

Figure 13.2: A three-part firewall system

Figure 13.3: Modules of a SAFE network design