Assessments - 4, GPA: 3.3
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When the condition is corrected, the port is automatically reconnected. • With the jabber lock-up function, the hub automatically stops transmission of abnormal Ethernet frames that may cause data loss for all network users. (Jabber refers to abnormal Ethernet frames which are much too long and may come from a malfunctioning Ethernet card.) • With automatic polarity detection, the hub recognizes and adjusts for attached cable assemblies which may be wired with incorrect polarity on the receive pair. Product Overview Chapter 2: Installing the System This chapter provides information on installing the Fast EtherHub-12s, establishing network connections, and configuring the system. You may install this hub on any level surface (e.g., a table or shelf) or in a standard EIA equipment rack. However, please take note of the following minimum site requirements before you begin. Pre-Installation Requirements Before you start actual hardware installation, make sure you can provide the right operating environment, including power requirements, sufficient physical space, and proximity to other network devices that are to be connected. Verify the following installation requirements: • Power requirements: 100 to 240 VAC (± 10%) at 50 to 60 Hz (± 3Hz). The hub’s power supply automatically adjusts to the input voltage level. • The EtherHub should be located in a cool dry place, with at least 10 cm. of space at the front and back for ventilation. • Place the hub out of direct sunlight, and away from heat sources or areas with a high amount of electromagnetic interference. • Check if network cables and connectors needed for installation are available. • Find a suitable location at the center of the devices you want to link, and near a power outlet Installing the System Fast EtherHub-12s User’s Guide Connecting the Hub System This hub is a Fast Ethernet repeater for 100BASE-TX networks. The EtherHub-12s has 12 RJ-45 station ports, of which Port 12 can serve as either a station port or a daisy-chain port (depending on the port’s switch setting). The station ports allow you to make connections to devices such as a workstation, server or router. You can also cascade to another compatible hub or switch by connecting an MDI port on one device (e.g., port 12MDI on this hub) to an MDI-X port on the other device. Or you can cascade from an MDI port on another device to any MDI-X port on this hub. See Figure 4.1. Making a Connection via an MDI-X Station Port You can connect an RJ-45 station port on the hub to any device that uses a standard network interface such as a workstation or server, or also to a network interconnection device such as a router (depending on the port type implemented). 1. Prepare the network devices you wish to network. Make sure you have installed suitable 100BASE-TX network interface cards for making a connection to any of the hub’s station ports. You also need to prepare straight-through shielded or unshielded twisted-pair cables with RJ-45 plugs at both ends. Use 100W Category 5 cable for all connections. 2. Connect one end of the cable to the RJ-45 port of the network interface card (or comparable port type) on the device you are attaching to the hub, and the other end to any available (MDI-X) station port on the hub. When inserting an RJ-45 plug, be sure the tab on the plug clicks into position to ensure that it is properly seated. Using the hub in a stand-alone configuration, you can network up to 12 nodes. Do not plug a phone jack connector into the RJ-45 port. This may damage the hub. • Use only twisted-pair cables with RJ-45 connectors that conform with FCC standards. Notes: 1. When connecting to station Port 12, set the port selection switch to MDI-X. 2. Make sure each twisted-pair cable does not exceed 100 meters. Installing the System Fast EtherHub-12s User’s Guide Making a Connection via the MDI Daisy-Chain Port 1. To make a direct connection to another compatible repeater or switch, use the 12MDI daisy-chain port. When connecting to this port, remember to set the port selection switch MDI. 2. Prepare straight-through shielded or unshielded twisted-pair cables with RJ-45 plugs at both ends. Use 100W Category 5 cable for all connections. Connect one end of the cable to Port 12MDI on this hub, and the other end to a standard MDI-X station port on the other device. When inserting an RJ-45 plug, be sure the tab on the plug clicks into position to ensure that it is properly seated. Notes: 1. When connecting to Port 12MDI, set the port selection switch to MDI. 2. Make sure the length of twisted-pair cable does not exceed 100 meters. 3. To connect to another hub or switch, you may also run straight-through twisted-pair cabling from a station port on this hub to a crossover port on another device. However, if you must connect to another device via station ports at both ends of the cable, use crossover cabling. Distance Limit for Fast Ethernet Cabling There are two common ways to calculate maximum cable len...