9Attenuation and NoiseJean Andrews: A+ Guide to Managing and Maintaining Your PCJean Andrews: A+ Guide to Managing and Maintaining Your PC
10Cable Management Patch Panel Punch-down Block Tamara Dean: Network+ Guide to NetworksPunch-down BlockTamara Dean: Network+ Guide to Networks
11Cable ManagementCareful attention to the cable plant gives fewer physical layer network problems. Pay careful attention to cable fabrication and cable installation techniques.A cable which is working fine at 10 Mbps may not work well at 100 Mbps.Use patch panels and punch down blocks to break up and organize cable runs.TIA/EIA 568 Commercial Building Wiring Standard.
12Fiber Optic Cable Structure Tamara Dean: Network+ Guide to NetworksGlass CoreGlass CladdingPlastic CasingKevlarPlastic Sheathfibers / cable(see pg 124 in Roberts text)Tamara Dean: Network+ Guide to Networks
13Fiber Connector Types (SM & MM) SC - Subscriber/Standard ConnectorST - Straight TipTamara Dean: Network+ Guide to NetworksMT-RJ - Mechanical Transfer Registered JackLC - Local ConnectorSC, ST - Existing fiber networksLC, MT-RJ - Newer fiber networks - Smaller size allows higher density of connections at termination pointFC - see pg 135 in Roberts textTamara Dean: Network+ Guide to Networks
20Physical Bus Topology Traditionally Thinnet or Thicknet coaxial cable Signal propagates in both directions from the point of originRequires 50-ohm termination transistors to prevent signal bounceGoodLeast amount of cabling - inexpensive to set upBadOnly one communication channel, thus every node shares the bus's total capacity - network performance degrades as nodes are addedRarely practical for networks with more than a dozen nodesHighly susceptible to single element failure
26Physical Topology ≡ Logical Topology ? Physical pattern formed by physical layout of media and connectivity devicesLogical TopologyPattern formed by the flow of data packets, how data flows from device to deviceConsider a physical star / logical ring configuration
32Hub vs. Switch Hub Switch Only one transmission at a time Single collision domainPacket is sent to all portsSwitchSimultaneous transmissions without collisionsCreates multiple collision domainsPacket is sent to a single port