Network Routers

A DSL router is a combination of a DSL (digital subscriber line) modem and a routers. The DSL modem allows for the sharing of broadband data with normal audio services on telephone lines. This is achieved by sending the internet data at higher frequencies than audio and by separating the audio and data communication with an in-line filter (DSL filter). The routers provides the capability for local area network (LAN) and wireless LAN (WLAN) attached devices to communicate with each other and to share access to a broadband wide area network (WAN). The most common type of DSL routers are ADSL routers, (Asynchronous DSL). The routers are asynchronous because they optimize the data transfer for higher download speeds at the expense of the upload speed. Typical transfer speeds for DSL modems are from 128kbits/s to up to 100Mbits/s dependent upon the underlying technology. It is the dominant method of internet access globally due to its compatibility with existing copper telephone lines. The routers connects the wide area network (WAN) broadband internet interface to devices and computers on the attached local area networks (LANs). It allows devices and computers on the local area networks (connected to the router's LAN ports) to communicate with each other. The routers interpret packet addresses and intelligently forwards them to destination devices that are connected to the LANs or to and from the internet cloud through the WAN port. It does this by comparing the packets to a table of interconnection rules called a routing table and routing policies. Most DSL routers incorporate sophisticated network management functionality. This includes filtering, firewall services, Network Address Translation (NAT), and special purpose drivers called Application Level Gateways (ALGs). ALGs allow applications like gaming and file transfer to communicate securely and efficiently. Most DSL routers incorporate a wireless modem (Wi-Fi) to enable devices on wireless LANs (WLANs) to connect. Administrators can usually configure access rights for devices based on their device address, and some routers can also set access times for devices. DSL routers typically incorporate wireless connection, security and encryption protocols (WEP, WPA and WPA2). DSL chip suppliers have recently demonstrated DSL connection speeds of up to 1Gbit/s on existing infrastructure as a competitor to fiber role out. This is planned to be available in homes in 2016 and will allow high definition movie downloads in less than half a minute.