Networking Accessories

Bridge

A device that connects two local-area networks (LANs), or two segments of the same LAN. The two LANs being connected can be alike or dissimilar. For example, a bridge can connect an Ethernet with a Token-Ring network. Unlike routers, bridges are protocol -independent.  They simply forward packets without analyzing and

re-routing messages. Consequently, they're faster than routers, but also less versatile.

Router

A device that connects two LANs. Routers are similar to bridges, but provide additional functionality, such as the ability to filter messages and forward them to different places based on various criteria. The Internet uses routers extensively to forward packets from one host to another.

Switch

In networks, a device that filters and forwards packets between LAN segments. Switches operate at the data link layer (layer 2) of the OSI Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs.

Concentrator

A type of multiplexor that combines multiple channels onto a single transmission medium in such a way that all the individual channels can be simultaneously active. For example, ISPs use concentrators to combine their dial-up modem connections onto faster T-1 lines that connect to the Internet. Concentrators are also used in local-area networks (LANs) to combine transmissions from a cluster of

nodes. In this case, the concentrator is often called a hub or MAU.

Gateway

A device which is used to connect networks using different protocols so that information can be passed from one system to the other.  Gateways functions at the Network layer of the OSI model. A Gateway many of the times is simply – Hardware-wise  PC with Both Media Device Interface (NIC’s) and some sort of Software that does the actual conversion of protocols and data packettes.

Multiplexor

A communications device that multiplexes (combines) several signals for transmission over a single medium.  A demultiplexor completes the process by separating multiplexed signals from a transmission line.  Frequently a multiplexor and demultiplexor are combined into a single device capable of processing

both outgoing and incoming signals.  A multiplexor is sometimes called a mux.

Multi-Port Repeater or Intelligent Hubs

So-called intelligent hubs include additional features that enables an administrator to

monitor the traffic passing through the hub and to configure each port in the hub. Intelligent hubs are also called manageable hubs.