Overview
The 2E253-49R is a 48-port high-speed network switching device that supports traditional switching (bridging) and Cabletron Systems SecureFast Switching Virtual Network technology. The optional HSIMs provide one or more additional ports for high speed uplinks to networking technologies such as Fast Ethernet, Gigabit Ethernet, Fiber Distributed Data Interface (FDDI), Wide Area Networks (WANs), and Asynchronous Transfer Mode (ATM). The HSIMs also provide additional Fast Ethernet ports in varying media types. The optional VHSIMs provide very high speed uplinks to networking technologies such as Gigabit Ethernet and ATM.
The 2E253-49R ports can be configured to control frame traffic in several ways, including prioritizing traffic flow according to protocol type. The 2E253-49R can also be configured to establish Virtual Local Area Networks (VLANs) and control the flow of frames associated with each VLAN according to priority and Ether type. Detailed information about VLANs is provided in the Cabletron Systems SmartSwitch Series 2E253, 2H252, 2H253, and 2H258 Local Management User’s Guide.
The 2E253-49R may be used as a tabletop unit or can be installed in a standard 19-inch rack using the supplied rack mounting hardware.
The 2E253-49R has two universal ac power supplies with automatic voltage sensing that allows operation using 100–125 or 200–240 Vac, 50/60 Hz. The power supplies load share 50% (+/-5%) of the power required by the device. If one power supply fails, the remaining power supply assumes the entire load of the device without interruption to network traffic. Each power supply module supports its own ac input connection, which allows the user to connect each power supply to a different ac power circuit.
1.1.1Connectivity
The 2E253-49R connects to Ethernet networks or workstations through four 50-pin RJ21 connectors. Each connector is wired for 12 ports. These ports support Unshielded Twisted Pair (UTP) cables with an impedance between 85 and 111 ohms at lengths up to 100 meters. The ports are IEEE 802.3 10BASE-T compliant.
The device also has a slot for an optional HSIM or VHSIM to provide additional connectivity to various networking technologies.
1.1.2Full Duplex Switched Ethernet
Each switched Ethernet port supports full Ethernet communications and can be configured to operate in Full Duplex Switched Ethernet (FDSE) mode. FDSE allows each port to provide a dedicated 20 Mbps bandwidth for file server or high-end workstation connections.
