USRobotics U.S. Robotics SureConnect ADSL Ethernet/USB Router manual

U.S. Robotics SureConnect ADSL Ethernet/USB Router User Guide

instruments, modems, and fax machines to a female RJ-11 jack. The female jack often mounts to the wall or floor.

RJ-45- Eight-conductor modular telephone jack. Used for 10BaseT, ISDN and other data connections.

Router - Device that forwards data packets between local area networks (LANs) or wide area networks (WANs). Referring to routing tables and routing protocols, routers read the network address in each transmitted packet. Routers then decide where to send the packet. A router bases this decision on the best route. When a router port detects a packet, the router checks the routing table. The port attempts to match the network number of the destination IP address with its routing table entry. If the port finds a match, it forwards the packet to the destination network. With no match, the port forwards the packet to a router defined as the default gateway.

RT-VBR (Real Time-Variable Bit Rate) - Service type that supports time-sensitive applications such as voice. Varies the rate at which cells arrive.

S

Sideband - Band of frequencies adjacent to the carrier. Modulation of the carrier creates sidebands. The sidebands contain the signal data, but consume bandwidth beyond what the carrier needs. In some cases, circuitry may suppress duplicate sidebands without harming the signal data. For instance, AM becomes single sideband when circuits delete one of two identical AM sidebands. Some single sideband equipment also suppresses the carrier frequency. The carrier must then be restored at the receiver before the signal can be demodulated, that is, recovered.

Spanning Tree-Bridging- Particular algorithm or formula. Transparent bridges use the spanning tree algorithm to dynamically determine the best source-to-destination path. This algorithm avoids bridge loops (multiple paths that link one segment to another) within a network. The algorithm determines all redundant paths and makes only one of them active. The spanning tree protocol (STP) is part of IEEE standard 802.1.

Splitter - DSL device that accommodates analog telephones, plus digital data access over the Internet. With a splitter, analog voice signals transmit at baseband frequencies. These combine with passband data transmission through a low-pass filter.

Static routes - Permanent routes that the router stores. The router uses these routes when determining where to forward IP packets that it receives.

Subnet Mask - Portion of a network. Distinguished from other portions by the use of a mask or subnet number. Subnet masks split one network into a set of mini networks or subnets. Subnetting helps to reduce traffic on each subnet. Subnetting also makes the network more manageable. Each subnet functions as if it were an independent

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