Basic Network Management - Chapter 12: WAN Overview

Chapter 12: Wan OverviewObjectiveWAN Transmission TechnologyLeased LineADSLPSTNIntroductionIn order to take advantage of WAN services, local networks and individual users must select a method for gaining access Service providers offer a wide range of WAN access optionsEach designed to meet a specific set of transmission needs in an efficient and cost-effective manner WAN OverviewWANs connect remote sites.Connection requirements vary depending on user requirements, cost, and availability.WAN TechnologyLeased lineFrame Relay ISDN (integrated services digital network) ADSLLeased LineProvider assigns connection parameters to subscriber.Leased Line What is “DSL”?• A family of access technologies that utilize high-transmission frequencies (up to 1 MHz) to convert ordinary phone lines into high-speed data conduitsADSL “Consumer DSL” • Designed to co-exist with POTS, unlike most other DSL types• “Slow” upstream for low-data-rate requests• “Fast” downstream for bursts of rich graphics and multimedia content•ADSL and POTS A Key Feature of ADSL Is Co-Existence with POTSCustomer PremiseCentral Office• Permits transmission of both signals on the same wire pair• Off-loads data circuit from the voice switch• “POTS Splitter” at the CO separates analog POTS from data• “Microfilters” at the customer premise prevent off-hookinterference between analog voice signal and ADSL signalADSL Access 10HeadquartersSmall Branch OfficeCisco 6x00(DSLAM)SerialADSLWANPSTNSummary Wide area networkLeased lineADSLPSTN