User manual D-LINK DE-824TP

[. . . ] Rack mounting produces an orderly installation when you have a number of related network devices. Use the six supplied screws to fasten the supplied mounting brackets to either end of the hub, then fasten the hub into the rack. Installing Network Cables Your Ethernet Hub is denominated as an 8-port, or 16-port, or 24-port Ethernet Hub according to the number of its front-panel 10BaseT ports. Additionally it has two ports whose connectors are on the rear panel: one 10Base2 port (BNC connector), and one 10Base5 port (AUI connector). [. . . ] It is only an alternative connector to Port 1, to facilitate hub-to-hub cabling. Port 1 is fully occupied whenever (1) a hub-to-hub connection is made through its Uplink connector, or (2) any kind of connection is made directly through the Port 1 connector. Below in this manual, the term " Uplink selected" will mean, as to the Model DE-816TP Ethernet Hub in question, that the subject connection is made through the Uplink connector Model DE-824TP Ethernet Hub The connector numbered as Port 1 is equipped with a switch labeled " Uplink" When the Uplink switch is in the " off" (tall) position, the Port 1 connector is wired " straight" to the supporting circuitry, and Port 1 is then identical with each of the twenty-three other numbered ports. When the Uplink switch is in the " on" (depressed) position, a pin interchange is switched into the wiring for the Port 1 connector, to provide a cross-over, and thus allow use of a straight cable to make a hub-to-hub connection. Below in this manual, the term " Uplink selected" will mean, as to the Model DE-824TP Ethernet Hub in question, that the subject connection is made through Port 1 and the Uplink switch is in its " on" (depressed) position. Rules for Using the Uplink Feature Uplink should never be selected for a station cable connection. And Uplink should never be selected for a hub-to-hub connection through a crossover cable (because the crossover in the connector wiring would cancel out the crossover in the cable). Uplink should be selected only for making a hubto-hub connection with a straight cable. When Uplink is selected at one end of a straight cable, Uplink must not be selected at other end of that cable. (If Uplink were selected at both ends of a straight cable, then the built-in crossovers of the two connectors would cancel one another, and the hub-to-hub connection would fail. ) Thus the rule for making a hub-to-hub connection with twisted-pair cable is as follows: To make a hub-to-hub connection with a straight cable, Uplink must be selected at one end of the cable, and Uplink must not be selected at the other end of the cable. To make a hub-to-hub connection with a cross-over cable, Uplink must not be selected at either end of the cable. Thin Coaxial Cable Connections To connect the Ethernet Hub to a thin coaxial cable (10Base2 cable, also known by its wirestandard name, RG58A/U, and a variety of other informal names), first twist a BNC T-connector onto the rear-panel BNC connector of the Ethernet Hub. Then twist the shell of the cable's connector onto either leg of the BNC T. If the thin coaxial cable continues on to other nodes, then twist the shell of the continuation cable onto the remaining leg of the BNC T. If there is no continuation (the Ethernet Hub is at the end of the coaxial cable), then it is necessary to twist a 50-ohm terminator onto the remaining open leg of the BNC T. Sometimes several Ethernet Hubs must be colocated to support a larger array of stations than can be handled by a single Ethernet Hub. Then it is useful to stack the Ethernet Hubs by joining their BNC connectors with 0. 5 meter patches of thin coaxial cable. Such stacking is just a special case of thin coaxial cable connection as treated above, and the terminator rule is the same: If the stack is at the end of the incoming cable, then a 50-ohm terminator must be substituted for the continuation cable shown in the stacking diagram below. Thick Coaxial Cable Connections To connect the Ethernet Hub to a thick coaxial cable (10Base5 cable), it is necessary to have a 10Base5 Ethernet transceiver (tap) on the cable at the Ethernet Hub's position. Then run an AUI cable between the transceiver's AUI connector and the AUI connector on the rear panel of the Ethernet Hub. Connecting Power For compatibility with electric service in most areas of the world, the Ethernet Hub's power supply automatically adjusts to line power in the range 100 - 250 VAC and 50 - 60 Hz. Per ordering option, either a Type 1 (US) or Type 2 (European) power cord is supplied with your Ethernet Hub. See Spefications, below, for power cord details. [. . . ] Intermittent flashing yellow of the Collision LED is normal; the contending adapters resolve each collision by means of a wait-then-retransmit algorithm. Fre-quency of collisions is an indicator of heavy traffic on the network. Link/Rx LEDs One Link/Rx LED for each numbered port. Steady green (Link state) indicates that the port has good linkage to its partner device. [. . . ]