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r----- ControllerGabFne! - - --- � <br />I I <br />I I <br />I <br />RS-232 I Fiber Opuc Cable <br />ablo <br />Traffic Sirnial Controller Fiber Optic I <br />I <br />Modern j <br />I <br />- - - - -- wo ----- - - - - - <br />I � <br />I I <br />I ; <br />I ; <br />RS232 �� ! <br />I FiberOpti: <br />1 Modem ; <br />Central Traffic Signal <br />System Server I <br />I — — — — — — — — — — — — — — — — ° — <br />Figure 7. Direct Fiber Optic Connection Example <br />Network Fiber Optic Connection <br />More commonly fiber optic cable is used to connect devices to a larger multi -path backbone or <br />distribution network. If a fiber optic cable on a multi -path backbone network gets cut or <br />damaged, data is automatically communicated to its destination by being rerouted on the <br />network in another direction that will get it where it needs to go. Figure 8 illustrates an example <br />of a traffic signal connection to a network where Ethernet switches are used in the controller <br />cabinet and at the network hubs and centers via fiber optic cable. Typically a managed Ethernet <br />edge switch is used at the device level, a central Ethernet switch is used at the main network <br />hub, and Ethernet hub switches are used throughout the network to combine communications <br />channels on to shared fiber strands. Cat 5e cables are used to transmit data between the <br />Ethernet switch and the field device or server. Although many newer devices are Ethernet - <br />ready, other devices may require additional equipment to convert serial analog data to <br />IP /Ethernet. For example, the City's existing Model 170 traffic signal controllers would require <br />the installation of an Ethernet - enabled modem card to utilize Ethernet over copper <br />communications. <br />Analog <br />CCTV <br />Carnera <br />I Conlmlfer ! <br />1 <br />I <br />I Enerne4Enebletl <br />Video I <br />Modem Card <br />Encoder <br />I <br />I <br />m <br />U I Gt }' <br />ry % <br />rc <br />S U I Network <br />Cabs <br />I <br />rrber <br />�.�,!iy■ <br />I 0 tic <br />he <br />Managed I <br />I 170 Trafbc <br />Ethernet <br />I Signal Controller <br />--- — — — — — — <br />Edge Sywich <br />— — — — — — -- _ <br />- ----- -- - - - - - <br />Network Nub <br />I 7 <br />I <br />I i <br />Fiber I <br />Optic I <br />Cat 5`9 <br />..a e I Cable c I <br />I <br />I Central � I <br />Ethernet ; <br />Stitch Contra! Server <br />I <br />I <br />Figure 8. Network Fiber Optic Connection Example <br />DKS Associates Eugene Master Traffic Communications Plan March 2008 ' <br />Page 23 <br />