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Local Area And Wide Area Networking

Non techies can be forgiven for getting very confused with regards to Networks the hardware used and it's configuration, most would want or believe the hardware should work form the CD it comes with. This however is not always the case, if it is a router modem you are after their is no need what so ever to use the CD provided by the ISP (Internet Service Provider) or that of the Router manufacturer. This is true of all routers whether you buy a router over the counter or if this is provided by your ISP. Put simply a network is an electrical connection between you the consumer and that of the Internet via a service provider, a small device known as a router manages this connection between you, your Local Area Network and that of the Internet.

Connecting to the Internet

There are a plethora of terms concerning networks, Adsl router tcp/ip to name but a few, it may surprise you to learn there is more than one type of network only some of which we cover here, you may even already be using these networks and not know it.

ISP (Internet Service Providers)

ISP Speed Transfer Rates

UK ISP Non commercial transfer rates to the home or small businesses, vary from approximately 512Mbits to upto 8Gbits Downstream, higher downstream rates are possible but as of Dec 2007 such speeds are only attainable via cable television networks and generally not to everyone in every area, this due to lack of hardware infrastructure within the various counties (for the most part roads must be dug up for this sought of cable infrastructure). Whatever the claim made by any ISP you will never get anything close to the stated speeds highlighted by the service provider, this is partly due to distance from your main telephone exchange, but also as a result of shared hardware resources. Such sharing is known as "Contention Ratio" normally two contention rates apply with most ISP's offering 20:1 and 50:1 these values relate to the number of people who may share a common node or access point, so for example 50:1 ratio means upto 50 homes sharing one access node. A ratio of 20:1 ratio will provide upto twenty homes sharing one access node. It's not difficult to understand which one is better, such connection rates come at a premium and there is the inevitable trade off. 20:1 Contention Ratios are generally available to anyone who want's one however the stream rates rarely increase at the same frequency as that of domestic networks and considered for business use. To give you an idea of what I mean lets look at a router with four ports (bear in mind this is a simplistic view) if you connect four PC's to each of the four ports on the router then in effect each PC has a four to one 4:1 contention ratio, each PC is sharing one network resource. The downstream rates are seldom a limiting factor, what tends to limit any Internet network is the upstream rate as these are far less favorable than the downstream rates making backup's and Virtual Private Networks across the Internet limited to the maximum available upstream rate.

There is one other less common high transfer rate downstream anyways which is Satellite which are measured mega and gigabytes however such advantageous download speeds are negated by the upstream speeds measured in megabits not megabytes at best.

Analog Modems

There are three types of connection possible to the Internet now days the first is a Analog Modem typically considered legacy there are two component types one fits into your computer using a card ISA or PCI the other sits along side and connected via a serial port cable to that of your computer. These hardware and so called software analog modem connection types are seldom used as the transfer rates are painfully slow and usually considered unsuitable for modern day internet networking.

• Analog Modem upto 56K bits per second extremely slow

USB Modem Routers

The next device you could obtain is Modem Router such devices are connected to the computer using a standard USB (Universal Serial Bus) typically they have no firewall protection inside them. Both the Analog Modem and Router Modem are direct links from the Internet to that of your computer with nothing between them to block attacks from outside your own network. Both the Analog Modem above and this require the initiation of a dialup sequence from the computer to negotiate a connection to your ISP.

• USB Router Modem not as slow as the first but requires a dialup connection from the computer.

Router

There are many different types of Routers you can get, but essentially the one you require will fall into one of three categories.

• Standard
• Cable
• Wireless

Standard

A standard modem an example of which (although we use this product ourselves we take pains not to endorse this product over any other) is the Netgear DG834 ADSL (Analog to Digital Subscriber Line). It is also possible to obtain PCI ADSL Card versions these however will need drivers to operate them and generally not considered as good as the flat brick type.

The above comes equipped with a single RJ11 connector this is connected to your ADSL Phone line, this unit does not itself require a filter to be attached but due to the fact that it may use an RJ11 connector at each end a filter provides the conversion necessary, and the addition of a filter makes possible the use of a phone also. It also comes supplied with an ethernet cable to connect the router to the computer. If you want to use both a telephone and the router from the same telephone access point you will need to use a filter. The router has four RJ45 connectors or ethernet ports which allow for shared simultaneous internet connection and or connection to peripheral hardware. Only a phone requires a filter not the router so provided you are not intending to use the internet with a telephone you can connect to the BT socket directly.

When deciding on broadband cheap does not mean best, however advising on Service Providers falls outside the scope of this document, you will need to conduct your own homework to find out what other people think of their Service Providers for any given area.

When deciding on your type of Broadband you need to ask yourself some questions.

• The connection coming into your home where the Broadband will reside. Can you use your Television cable provider, if the answer to this is yes your router needs to be NON ADSL. Typically a connection via a cable company will typically support much high transfer speeds than that available over a BT Line. However due to corporate restrictions this is not the sought of connection we would recommend business customers although it should be markedly faster both upstream and down.

• Is the connection into your home only via Telecom cabling if this is the case you will need either a standard ADSL Router or Wireless ADSL Router.

• Is the connection you provide in your home or office the type that requires the use of Laptop and handheld internet connection devices. If your answer to this is yes you will need a ADSL Router with Wireless option.

Cable

Cable routers are not terribly different from from the above ADSL router, the difference of course is that the preferred WAN transport on cable is closer to that of Ethernet via TCP/IP than ADSL. Broadband via cable tends to be much faster than that which can be obtained from ADSL in both up and downstream mode, if it has a disadvantage it is that a large portion of the UK (United Kingdom) population has no access to this faster network. The router itself is not a lot different either, if fact because all three types are called routers it makes identification before purchase very difficult and with no one to ask over the Internet next to impossible to choose the right model. Cable routers have almost the same rear configuration as that of the ADSL router, instead of an RJ11 however it has five RJ45 instead of four one of the RJ45 is separate from the others and denotes the connection from the Cable ISP. The remain four connections would be used as before.

The Netgear WPN824 is not just a Cable router but also a Wireless access point it is therefor possible to configure within it's setup to use the LAN as is and or one or more wireless connections. One thing to remember with this sought of connection be sure to reset the Cable Set that came from your Cable Service Provider.

Wireless

There is two ways to setup a Wireless Access Point either directly via ADSL or directly via Cable we have already explained the connection via Cable (Above). A wireless connection via ADSL is the same as an ADSL router connection and wired in exactly the same way. Such a wireless connection allows you to freedom of the house as you are not restricted to an Internet connection from any one room as you would from a wired connection. However and this is the point wireless connection are inherently more dangerous by way of data interception and data theft unless suitable security is provided, and even then although very difficult to break it is still possible.

Be your connection ADSL or Cable using Linux Windoz or Mac we recommend you always ignore any CDs that your ISP may supply to you. DO NOT INSTALL any of these CDs despite what your booklet might say into your computer, your computer does not need drivers for any routers that may be attached just common sense and cabling.

Most modern computers come with an Ethernet port or ports as does your router. Your Router is supplied with two different cables one that is thin and will connect to the ADSL filter and the second which comes out of the back of the Router and into your computer itself, just match the cable to the socket, it is that simple.

When your computer is connected to the router switch on first the router and then your computer your computer will automatically detect and be assigned an IP address from the router. Look at the bottom or underside of your router you will see a group of four numbers "192.168.0.1" these numbers correspond to the IP address of the router itself. Armed with this information you can now access and program your router from your computers web browser.

With most ISP's but not all you will need to know the ADSL if your connection is Telecom, username and connection password, these usually look similar to that of a user email address but longer and strangely cryptic password. Be sure to have both of these before you proceed further, if your connection supports it.