Telex KP-812, Руководство пользователя

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28 RVON-1 User Manual
LAN - A LAN is a computer network that connects a relatively small area (a single building or group
of buildings). Most LANs connect workstations and computers to each other. Each computer
(also know as a “node”), has its own processing unit and executes its own programs; how-
ever, it can also access data and devices on the LAN. This means that many users can
access and share the same information and devices. A good example of a LAN device is a
network printer. Most companies cannot afford the budgetary or hardware expense of provid-
ing printers for each of its users. Therefore, one printer (i.e., device) is placed on the LAN
where every user can access the same printer.
The LAN uses IP addresses to route data to different destinations on the network. An IP
Address is a 32-bit numeric address written as four numbers separated by periods (For
example, 1.160.10.240.
Port - A port , when referring to TCP and UDP networks, is an endpoint in a logical connection. The
port number identifies the type of port it is. For example, port 80 is used for HTTP traffic.
Routers - A router is a device that forwards data packets over networks. Most commonly, a router is
connected to at least two networks (normally LANs or WANs). Routers are located at gate-
ways, the place where two networks are connected. Routers do little data filtering, they
mainly deliver the data.
Subnet - A subnet is a portion of a network that shares a common address component. On a TCP/IP
network, a subnet is described as all computers or devices whose IP Address have the same
prefix.
Switches - A switch is a device that filters and forwards data packets between networks. Switches
operate at the data layer, and sometimes at the network layer.
WAN - A wide area network connects two or more LANs and can span a relatively large geographi-
cal area. For example, Telex Headquarters in Burnsville, MN is connected to several of its
branch offices in Nebraska and Arkansas over the wide area network. The largest WAN in
existence is the Internet.