ADSL Beginners Guide: Connectors

Wiring diagrams for micro-filters are shown below (scroll to the end of the page, or click here).

Connector Types

	RJ11 Broadband/Telephone Plug The US style RJ11 plug is a 4 pin version of the RJ45 pictured below. It is the smallest in size and is used in the UK for DSL/Broadband Internet connections (RJ11 to RJ11).
	British (Telecom) Plug The familiar British telephone plug used in over 30 countries around the world. Any analogue device that operates over a telephone line will be connected using this plug. You will often find an RJ11 plug on one end, and a BT plug on the other (RJ11 to BT).
	USB Type A (Computer) Universal Serial Bus (USB) is the most popular way of connecting peripherals to your computer. To connect most devices, you will require a type A to B cable (often supplied with the product).
	USB Type B (Peripherals) The other end of the USB wire features a square shape plug designed to connect to peripherals such as your USB DSL modem or router.
	RJ45 Ethernet Network (Crimped Plug) The RJ45 connector, featuring 8 pins, is the big brother of the RJ11 It is used for data communications, specifically Local Area Networks (LANs). Cables can be either straight (for normal use between a hub and a computer) or crossed (for use between two hubs or switches). Each computer requires a Network Interface Card (NIC) to connect to the network.
	RJ45 Ethernet Network (Moulded Plug) The moulded RJ45 plug shown to the left performs exactly the same purpose as the crimped version above. Professionally constructed cables are usually moulded by a machine instead of crimped using a special device called a "crimping tool".

Wiring Diagrams

Basic diagrammatic scenarios are based upon:

Internet connection via a USB Modem
Internet connection via an Ethernet router/modem
Connecting additional telephone sockets

Beware! a certain amount of software configuration must also be carried out before computers and network peripherals are able to operate or communicate with each other. This includes software driver installation for USB modems, and the correct assignment of IP addresses and related parameters for Ethernet networks.

USB Modem

The easiest, and most popular way to get a single computer online with is via a USB modem. The process involves connecting the USB modem to the DSL side of your micro-filter, and your computer to the USB modem using a standard type A to B USB cable. Software installation procedure will vary depending upon the equipment purchased.

Many users choose to share their USB Broadband connection using software such as Microsoft Internet Connection Sharing (ICS). In this scenario, the computer will act as a gateway for other computers to access the Internet via a Local Area Network (LAN).

The same concept can be extended to wireless network cards instead of the more restrictive fixed approach above. This configuration is often referred to as "ad-hoc networking mode" with the sharing computer operating in "infrastructure mode". Most users will find that sharing their USB connection over a wired network is adequate.

Ethernet Router & Local Area Network

The following diagrams show sample configurations for Internet access via an Ethernet router/modem. Many routers feature a 2, 4 or 8 port inbuilt Ethernet hub or switch (a device used to connect computers together). In this scenario, computers can be connected directly to the router. Each computer is wired using a standard Ethernet cable with one end connected to a spare port on the inbuilt hub/switch and the other end connected to the computers network card.

If your Ethernet router only has 1 network port, or you want to connect more devices to the network than there are available ports, a Ethernet switch can be used in combination with a crossover cable to extend the size of your network.

Micro-Filters and Additional Telephone Sockets

Micro-filters must be used to separate the two different frequency bands used over your telephone line (voice and data) and prevent your analogue devices from interfering with the Broadband frequency ranges used by your modem/router.

Simple method: Walk around your house and count how phones are plugged into a phone socket (on the same line) and order the same number of micro-filters. Simply unplug each phone, plug them into the splitter and reconnect to the phone line.

Cheaper method: Buy a single micro-filter and plug this into your master socket and run all the phone extensions off the phone side of the micro-filter. Finally, run an extension from the ADSL side of the splitter to where you want to use your ADSL modem.