Basic Networking Tutorial
Here is a basic tut on networking. It assumes that one at least understands pc's, the underlying networking protocols, and instalation of the same at the bare minimum. It's just to give a basic overview to people that already know hardware and software but would like to know what is involved in building a network before jumping in.
As far as popular networks and cost effective ones go. The accepted standard is commonly referred to as "Fast Ethernet". This consists of several parts which we will get into later. Just a few of these are: routers, hubs, switches, and NIC cards.
Ok. So lets jump into this. What do I need to begin a network. Well, lets start with basics.
>>>>What do you need to start?
1. Nic Card (Network Interface Card):
The standard today is the 10/100 fast ethernet card. It is also wise to buy the same brands to make updates in firmware or drivers much easier. Also you may want to make sure that the cards you get are dual speed so you can connect other cards such as 10 BT. So when you have those LAN parties noone will be left out.
2. UTP Cable:
You will need this cable to connect the pc's to each other or to the hub depending on how you set the network up. The most commonly used is CAT5 cable. This is the standard and most common type used in networking. Distance constraints are also required when deploying CAT5 on a network. The limitations, we'll start with Network cables.
Ethernet LAN= UTP Max 328ft Min 8ft
Token Ring= STP Max 328ft Min 8ft UTP Max 148 ft Min 8ft
Fast Ethernet= 100BASETX CAT5 100 Meters,100BASET4 CAT 3,4,5 100 Meters
The connectors on this cable and the NIC cards that interface with it as well as the hubs are connected with RJ45 jacks. (They look like an oversized phone cord end and jack)
3. Hub:
Buy one with the correct spead and more ports than computers to ensure that you can expand your network buy adding more computers or hubs. Or for less hastle in configuration get yourself a managed switch or router. Routers are an excellent solution for broadband connections. It allows for all pc's on your network to be hidden from the outside and allows all your computers to navigate and utilize internet services. Plus it provides very basic "firewall" protection through NAT addressing. Switches are good for using internet sharing software or a proxy on your network. The router and managed switch are easier to configure than hubs are in general.
4. Software:
This one is a give me. You need to have software for drivers and protocol support for the pc's and devices.
>>>>Network Protocols
The thre major protcols are:
1. TCP/IP
2. IPX/SPX
3. NetBEUI
The one we will deal with here is the most common one.
TCP/IP (Transmission Control Protocol/Internet Protocol
Today this has been adopted by the UNIX operating system so this is now the most common protocol on PC LAN's. TCP/IP Settings (The most common settings, others abound but this is
the most common):
Dial up (Dialup Adapter)=
IP- Automatically assigned by the ISP (In most dial ups)
WINS- Disabled
Gateway- None (PPP is used to connect)
DNS- Usualy disabled, unless the ISP requires you to use their proxy server.
LAN (Network card. Mainly LAN's, CAble, DSL [Some DSL setups are different])=
IP- Must be a specific value. Ie.. on an internal network 192.168.1.1.
WINS- Indicate a server or domain or use DHCP to allow NETBIOS over
TCP/IP.
Gateway- IP address of gateway used to connect the LAN to the internet.
DNS- Enabled with the host and is a domain specified value.
>>>>Doing It
The basics.
A LAN is used for three main reasons:
1. To share files
2. To share printers
3. To share an internet connection
Ethernet is the most common LAN. Two other standards are the IBM Token Ring and Apple's AppleTalk. We will deal with Ethernet. The following is a basic worksheet to help you through the process of installing a network. It is impossible to cover all the different possible steps involved, so it is advisable to have an experienced technical person on hand to help with the details.
1. Determine what type of cable you will be using, and subsequently, if you will need a hub or switch, and figure out what size hub you need. A rule of thumb is to get a hub with 2-4 more ports than you have computers, so you have room for growth.
2. Count the number of NIC cards you need to buy. (new computers sometimes come with them).
3. Find out how much cable you will need – either from each computer to the next, or from each computer to the hub, depending on your set up. Make the cables a few feet longer than what you need to allow for moving the location of the computer.
4.Be sure you have the technical knowledge to cut and crimp your own cables, or buy your cables pre-cut and pre-made. If you buy cable and connectors, you have more freedom in running the cables, but you will also need to buy more equipment such as a combo cutter/crimping tool. Which can become expensive.
5. You may already have the software to network your computers, or if you may need to purchase network software. Windows products, most Linux and Macintosh systems already have it built in. You may purchase packages like Windows NT/ 2000 Advanced Server, Novell, or LANtastic, etc.
6. Double-check to make sure you have everything you need. Cable, network cards, hub, crimping tools, etc. Check the cards and make sure they have the right connection type for the cable you are buying. Do a test run between two computers, either directly on a CAT5 patch cable, or through a hub on CAT5 cable to make sure everything works.
7. Plan a day to do all the wiring, card installation, etc. It is generally easier to do all the computers in one batch than it is to do a couple today and onother the next.
Administrating a Network
Network administration is the most important component in keeping your LAN working smoothly. It requires regular, though not constant, supervision, so LAN administration should fall in the hands of a qualified person. Since there are many different types of LAN software,
from built-in Macintosh and Windows systems to separate packages like Novell it is impossible to cover all the different details here. However, there are certain aspects of LAN administration, which are similar no matter what system you are using.There are two models of software networking: Peer-to-Peera nd client-Server.
Peer-to-peer Means each computer communicates with each other computer on an “equal” basis, and is not optimized to share information over networks; client-server means that one machine is designed to run central programs (the “server”) which are then accessed by the other computers (“clients”).The main difference is that if you run a centralized program (like a database or print-server) on a peer-to-peer network, it will probably be slower than on a client-server database. However, this difference is not necessarily so clear when you are
actually running a network. The network software itself might be designed to be peer-shared files, and also runs a “server” version of your database. This means that although the network software is not optimized for this type of setup, your program is, so you are getting
some of the benefits. Keep a Map of your LAN. This is similar to inventory, and does not have to look like an actual map. It is always good to know which wire goes where, and which computer is connected to what cable, etc. If you are using CAT5 cable and a hub, it is good to
keep a record of which computer or printer is connected to which numbered port on the hub - this will save headaches later if you are troubleshooting.
Printer Sharing-
One of a network’s basic purposes is for several computers to share printers. This might require you to specify a particular computer, which will act as the traffic cop for files that need to be printed. Generally, once you have set up the print sharing, you do not need to regularly modify it, unless you are adding new printers or computers. Most LAN software comes with print sharing tools that will allow you to cancel print jobs, or delay print jobs for a later time (especially important if you accidentally printed 100 page manual right before someone wanted to print their grant proposal on deadline).
File Sharing-
Another basic function of a LAN is to allow computer users to “share” or copy files from one computer to another, without having to put it onto diskette. Usually, to get into another computer over the network, regardless of whether you are on a peer-to-peer system or a
server-based system, you need to “log on” to that computer (i.e. you need an ID and a password which gives you access to that computer). If the files are scattered in different computers, you can imagine how quickly things would get complicated if every computer had an ID and password for every other person. Therefore, if you are sharing a lot of files, or if several people regularly work on documents together, it’s always a good idea to have a “central” folder where these files are commonly kept. In small LANs, especially peer-to-peer ones, it’s easy to set up a folder on someone’s computer, and call the shared folder. On larger LANs, you would set up the “server” computer to do the file and print sharing. In any case, you now only need to set up IDs and passwords on that central computer. You can go one step further, and give certain people “privileges” to special folders, and restrict other people’s access to that folder. The typical example is sensitive financial documents that only accountants and managers would be given access to see. Be careful, though, because as LAN administrator, it is your job to keep track of people’s IDs, passwords, and who has access
to what, and the more restrictions you have in place, the more difficult to keep track.
Internet Connection-
This allows several commputers on a LAN to share an internet connection. Several ways are availible to do this. ICS (Internet Connection Sharing) is a common one for a home or small business. It involves one of the commuters on the network to have an internet connection via dial-up, cable, backdone, dedicated line or DSL. It acts as a gateway to the other computers and can filter the trafic comming into or going out of the network. A server can also perform this function, but is not wise to do so if it has valuable information on it. You can also use a hardware firewall or router connected to a hub, switch or PC to act as a gateway or proxy server for the other computers on a network.
Summary:
You might have many other duties that fall to you as LAN administrator. These would include doing server backups; maintaining databases that are “shared” or accessible to people on the LAN; maintaining the connection to the Internet, if you have “dedicated” or direct connection from the LAN; and even running the central e-mail server. Administrating LANs is a lot ofresponsibility, and needs a committed person to do the work. However, if things are kept simple, documented, and maintained, the time spent administrating the LAN can be reduced
greatly. These are also great computer and organizational skills that will benefit you in any environment.
