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misguidedyouth
May 28th, 2006, 12:16 AM
NETWORKING FUNDAMENTALS

PLEASE, no one take offense if this is too simplistic! I'm sure there are many in these forums that have more networking experience than I . I'm writing this for people who are new to networking.

I'm going to break this up into parts instead of trying to put it all into one post. That way, you can be bored to tears (or on the edge of your seat?) in relatively small chunks, instead of all at once!

What's a Network?

A Network (I'll start with a Local Area Network) is two or more computers connected to each other most often using Ethernet, and Category 5 (or 5e) Cabling, or 802.11g Wireless.

A LAN can be used to share resources, like that precious Internet connection, printers, and to let you move information between your own computers.

How do you build a network?

In order to make two PC's "talk" over a network, each PC must have at a minimum, three things:

1. A Network Interface Card (NIC): Most likely (99.999% of the time) an Ethernet wired or wireless NIC.

2. A Protocol: Almost always TCP/IP.

3. A Client: For home users, almost always Microsoft Family Logon. Included in Client Configuration, is making sure all PC's that want to connect to each other are in the same Workgroup or Domain.

NIC - Wired or Wireless?

A Wired NIC should be a 10/100 Megabit Ethernet PCI Card.
A Wireless NIC should be an 802.11g Wireless PCI NIC.
Above, I said you'd want PCI Cards, but for a laptop, of course, you'll want PCMCIA (PC Card) NIC's.
A Laptop Wired NIC like Netgear PC Card NIC

Once your NIC is installed, (you must physically install the card, and make sure the software Drivers are installed correctly) you'll be able to "bind" a protocol to it.

PROTOCOL

The Protocol you use will be TCP/IP if you want to connect to the Internet. On some older Operating Systems, NetBEUI and/or IPX/SPX are on by default. I recommend turning those protocols off for home networks.

You're in luck! The Drivers for most network cards install TCP/IP for you!

To check what Protocols are installed, do the following:

Windows 98/Me:
Right click on Network Neighborhood (neighbourhood?) smile.gif on your desktop, and select Properties from the menu that comes up. Under the Configuration Tab, scroll down and make sure TCP/IP -> Your Network Adapter (your adapter name will be here) appears.

Windows XP(2000):
Click on Start, Control Panel. In Control Panel, click on Network & Internet Connections, then on Network Connections. (2000, just right click My Network Places on your desktop, then select Properties).

Right Click on Local Area Connection and choose Properties. Make sure Internet Protocol (TCP/IP) is listed.

I'll have much more (more than you want to know?) about TCP/IP in Part 2.

If your NIC is installed correctly, TCP/IP should be there. If it isn't, in the Network window you can click on Add, select Protocol from the Select Network Component Type window, click Add, click Microsoft in the left pane, and scroll down to TCP/IP in the right pane, then click Ok. If you don't know where your cab files are on the Hard Drive, you may need your Operating System CD for this.

CLIENT

Like TCP/IP, a Microsoft Client should be installed with the NIC Drivers.

To check your Client:

Windows 98/Me:
Right click on Network Neighborhood on your desktop, and select Properties from the menu that comes up. Under the Configuration Tab, scroll down and make sure TCP/IP -> Your Network Adapter (your adapter name will be here) appears.

Windows XP(2000):
Click on Start, Control Panel. In Control Panel, click on Network & Internet Connections, then on Network Connections. (2000, just right click My Network Places on your desktop, then select Properties).

Right Click on Local Area Connection and choose Properties. Make sure Microsoft Family Logon is there.

You can use the Client for Microsoft Networks, but you'll want to make sure the Client is NOT set to logon to a Windows Domain, if you don't have your own Server (most home users do not). To do this, in the Network window as above, select Client for Microsoft Networks, and click Properties. In the Client for Microsoft Networks Properties window, make sure Log on to Windows Domain under Logon validation is unchecked.

Workgroup

Ok, one last piece to the puzzle, the workgroup. In order for your computers to "see" each other, they will have to either be in the same Domain (primarily used for corporate networks) or workgroup (the home user’s choice).

To check your Workgroup:

Windows 98/Me:
Right click Network Neighbourhood, and select Properties. Click on the Identification tab. You'll see your Computer Name and Workgroup. Write them down. The Computer Name must be unique throughout your network and should be something meaningful to you (Kitchen, Laptop, something). The Workgroup name must be the same for all the computers you want to communicate with each other. The name isn't important, as long as it's the same throughout your network.

Windows XP/2000:
Right click on My Computer and select Properties. Click on the Network Identification Tab. Follow the same rules as above for naming the Computer and Workgroup.

Well, if you made it through all that, congratulations! I hope it's helpful with some of the fundamentals! Please let me know what you think about this..

misguidedyouth
May 28th, 2006, 12:22 AM
NETWORKING FUNDAMENTALS - Part2

There are VOLUMES of information about TCP/IP available on the Internet. My goal here is to give you what you'll need to setup a home network.

There's an introduction to TCP/IP, then I explain some of the hardware and software you'll need to do what you want safely on the Web. I'll also cover DHCP, and why I recommend using it.

In Part 3, I'll cover Sharing Resources on a Microsoft Network.

Networking behind the scenes
When you browse to a web site like http://www.xboard.us/bbb, what really happens? First, your computer resolves the name using the Domain Name System (DNS) and finds out the IP Address is [XXX.XX.XXX.XX]. Once it finds the IP Address, it will know whether the server is local, or on a remote network. After it knows the address, and knows it's on an external network, it sends a message to the website's server asking for the home page. The Server sends a reply, and poof! The page appears in your browser!

Since your computer is exposed to the entire Internet, especially if you have DSL or Broadband, you should protect yourself with Hardware and Software Firewalls.

I'll cover all of that below, but I'll begin with an explanation of TCP/IP and IP Addressing.

misguidedyouth
May 28th, 2006, 12:23 AM
Transmission Control Protocol/Internet Protocol (TCP/IP)
TCP/IP is a suite of protocols that allow communication between computers, and between networks. A Protocol is nothing more than a set of standards. You can think of it like a language. To communicate effectively, we need a common language or Protocol.

The primary part of TCP/IP I'll be focusing on is IP Addressing.

What's an IP Address?
I like to use an analogy I've seen used many other places. An IP Address is like a person's mailing address. The name, www.xboard.us/bbb is like the person or business name. The IP Address associated with that is like the Country/State/City/Street and House Number.

Take a look at your IP Address:

Windows 98/Me: Go to Start, Run, and type winipcfg. This brings up the IP Configuration window. You can see your IP Address, the Subnet Mask, and the Default Gateway. (you need to choose the right adapter)

Windows 2000/XP: Go to Start, Run, and type cmd. This brings up a Command window. In the Command window, type ipconfig. You'll see the same information in text format.

Parts of an IP Address
You'll notice that your IP Address is broken into 4 parts separated by periods, for example, 192.168.1.50. The parts are called Octets, and their values can range from 0 to 255 in each part.

How does the computer know which part is the Network (City/State, etc.) part, and which is the Host (house number) part? It uses the Subnet Mask to figure it out.

I'll keep the discussion very simple. There are different ways to divide the network and host portions up (Subnetting), but I'll stick to the scheme you should use on your home network (assuming you have your own router) here.

Here's the breakdown for your home network:

192.168. 1. 50: IP Address
255.255.255. 0: Subnet Mask
192.168. 1. 50
192.168.1 Network .50 Host

In this example, you're using a Class C Address Scheme.

I strongly suggest you stick to the 192.168.1.x network unless you have a reason to change, and unless you know about Private Addressing. If you use Virtual Private Networking (VPN) to get into your business network, and your company uses a 192.168.1.x scheme, you may have to change your IP. I know of no other major reason to change it.

If you need VPN help, please post a message and I'll get you working!

Dynamic Host Configuration Protocol (DHCP)
How do you know what IP Addresses are assigned, what ones are legal for your network, and how to configure your DNS information? You don't have to if you let your Router handle it by enabling DHCP on the Router and on your Computers.

DHCP on the Router
Most home Routers have a web browser interface. Open your browser (Firefox. ) and in the Address dialogue, type 192.168.1.1. (If this doesn't work, check your Default Gateway Address in your IP Configuration. That's the address to put into your browser). Some kind of Router interface should open up. Look for a setting or tab that says DHCP. Make sure DHCP is enabled. You'll want to write down your DHCP Scope (that's the range of addresses that will be used for your PC's), and the DNS Servers.

DHCP on the PC's
Important! If you have configured your IP settings manually, you should write down all of these settings as they are, before making any changes. You may want to put them back temporarily if DHCP doesn't work.

Windows 98/Me: Right click on Network Neighborhood on your desktop, and select Properties from the menu that comes up. Under the Configuration tab, scroll down to TCP/IP -> Your Network Adapter (your adapter name will be here). Highlight TCP/IP for your Network Adapter and click on Properties. In the TCP/IP Properties window, click on the IP Address tab and make sure Obtain IP Address Automatically is selected.

Under the Wins Configuration tab, make sure Use DHCP for Wins Resolution is selected.

Under the Gateway tab, there should be no installed Gateways. If there are, highlight and remove them.

Under the DNS tab, remove any configured servers. You can leave your hostname, but all other fields should be blank.

Windows 2000/XP: Click on Start, Control Panel. In Control Panel, click on Network & Internet Connections, then on Network Connections. (2000, just right click My Network Places on your desktop, then select Properties).

Right Click on Local Area Connection and choose Properties. Make sure Obtain IP Address Automatically, and Obtain DNS Server Address Automatically are selected.

Click Advanced and make sure there are no Gateways.

That's it!

Routing and Firewalls

Ok, you know your IP Address, you know what it means (kind of?), now what?

A Router is like a local post office. If you're sending a letter to someone in your own town, the letter does not have to be sent to another town's post office, so it stays local. If it bears an outside address, it has to be "routed" to a different post office, and it is sent out.

If you have only one computer and you connect directly to a Cable Modem, or DSL connection, your Internet Service Provider (ISP) has the Router.

If you have a LAN, you'll need a Router (it should be a Firewall/Router, but more on that later).

Routers
A Router has at least an Internal and External Port or Interface. Its only purpose is to take traffic from the Inside Port, and send it to the Outside Port if needed, and do the reverse for inbound traffic.

To illustrate, your computer's browser request goes to the Router (Default Gateway). The Router sends the request to Routers across the Internet until they get to the website's Server. Then the reverse happens to get the traffic back to you!

Out: 192.168.1.50 --> 192.168.1.1 --> Internet Routers --> 209.67.217.28
Back: 209.67.217.28 --> Internet Routers --> 192.168.1.1 --> 192.168.1.50

Everything's wonderful, right? Not really. There's a little problem with connecting to the Internet. There are many people scanning your computer for vulnerabilities and trying to attack you every day! How do you stop them? A Firewall, of course!

Firewalls
Firewalls basically permit traffic from Inside to Outside, but block traffic from Outside to Inside, unless it's been requested from Inside. Kind of like a flapper valve, or backflow preventer in a pipe. Except that some traffic (that requested from inside) is permitted back in.

For a Hardware Firewall, Inside means on your LAN, and Outside means on the Internet. For your PC, Inside means on your PC, and Outside means everything else. On both Hardware and Software Firewalls you should be able to permit traffic inbound when needed.

Hardware Firewalls
A Hardware Firewall, like this Linksys Firewall, or this Netgear VPN Passthrough Firewall will be all you need. (Get a VPN Passthrough capable Firewall if you VPN into work).

NAT vs. SPI?
Let's say you're shopping for a Firewall, and you see that the box says "Built-in NAT technology acts as a firewall to protect your internal network." WRONG! It makes me angry when manufacturers take advantage of the public's lack of knowledge like that. Notice the tricky wording "acts as a firewall". To the average person, they'll think they're well protected. It doesn't say it is a firewall!

Network Address Translation (NAT) (more accurately, Port Address Translation) is a normal procedure when you're using an internal network address scheme like the 192.168.1.0 Network so many home networks use. It is NOT designed to be a firewall. It can be overcome by sending fragmented packets, and may be spoofable.

Stateful Packet Inspection (SPI) on the other hand, was a technology developed for use in Firewalls. It keeps track of the "state" of communications between your PC and the outside world. It is much more difficult to break through an SPI Firewall than a NAT Router.

Bottom line, make sure you get a Firewall that does SPI!

Software Firewalls
Good news! There are some excellent Software Firewalls available for free! I'm listing two here, but there are more out there.

Windows XP Service Pack 2 Firewall - Microsoft has made some progress with the built in XP Firewall. This one's configurable, in that you can let some traffic through from the outside for home networking. It still doesn't warn you about unknown outbound traffic though! That means you won't know if a Trojan, Virus, or Spyware is trying to get out, nor will you be able to block it.

Zone Alarm - This version is free! They have pay versions, but the free one performs all the basic firewall functions you should need.

Sygate Personal Firewall - Another free version by a company that makes more powerful pay versions too.

Testing Firewalls
To test your Hardware Firewall, scan it from outside with Steve Gibson's Shield’s Up! scanner. It's fast and will tell you exactly what ports are insecure on your Firewall.

To test your Software Firewall, download and run Steve Gibson's Leak Test. It simply simulates an application you haven't authorized trying to get to the Internet. You should get a warning that an application is trying to get to the Internet. You say no, and make sure the test program is blocked.

Other Networking Gear

Switches & Hubs
If you buy any of the most popular home Firewalls, they have 4 to 8 Switch Ports built in. An in depth discussion of the difference isn't needed here. Just know that a Switch is a little better in some ways than a Hub, although the performance difference will be negligible for the home.

If you need a Switch, you can find one like this Belkin 8-Port Switch..

misguidedyouth
May 28th, 2006, 12:24 AM
Cabling
Ethernet NIC's, Router's, Switches, and Hubs use Category 5 (or 5e) cabling. Just get some Cat 5e patch cables and you're all set! Cat 5e will allow you to go to Gigabit Ethernet if you want.

Oh yeah, straight through, or crossover cables? It depends. For this discussion, we'll classify PC's and Routers as "smart" devices, and Switches and Hubs as "dumb" devices. Smart to Smart, or Dumb to Dumb, you need a crossover cable. Dumb to Smart or Smart to Dumb, you need a straight through.

PC to Switch Port on your Router/Firewall (Your Router's doing triple duty here, it's a Router, a Firewall, and a Switch, all in one!), you'll use a straight through cable. You usually only have to worry about finding a crossover cable if you want to go straight from PC to PC, or if you want to plug a Switch into another Switch (and even Switch to Switch, many have an Uplink Port or a Crossover Button alleviating the need for a crossover cable).

misguidedyouth
May 28th, 2006, 12:27 AM
Well, in addition to your computers being able to get to the Internet, you can share resources like Printer's and Files between computers. How do you do that? So glad you asked! smile.gif

Sharing Network Resources
To share windows resources, your computers must have network access to each other (this includes being in the same workgroup or domain), have a resource shared, and access must be granted to the shared resource.

Network Connectivity (Domain/Workgroup)
Your computers must be on the same LAN, or be connected by a Router that knows both networks, or be connected by a Virtual Private Network (VPN). I'll cover a LAN connection, since it's the most common configuration for home users. LAN Connectivity is covered in Part 1 and Part 2.

Once you have network connectivity, you'll have to make sure the computers are in the same Workgroup or Domain.

In a Microsoft environment, a Domain is used to connect computers that authenticate to a common Windows Server. Workgroups are used for home or peer-to-peer networking, so that will be my focus here.

Setting the Workgroup in Windows 98
Right click on network Neighborhood and click on Properties in the menu that comes up. In the Network window, click on the Identification tab.

misguidedyouth
May 28th, 2006, 12:31 AM
In the Network window, click on the File and Print Sharing button. A File and Print Sharing window what opens, click to check the box next to I want to be able to give others access to my files, I want to allow others to access my printer(s), or both, depending on what you want to share.



Click Ok, and Ok. Your computer will reboot. If you chose to share files, you'll still to right click a file, and share it as follows. You can share your entire Hard Drive if you wish, but I recommend against it. In either case, I recommend adding a password, and I'll show you how:

Sharing files or printers
Double click My Computer, then double click on your C: Drive to see all of your folders. Right click on a folder you want to share, for example My Documents. Select Sharing... from the menu that comes up.



From the Sharing tab, select Shared As, and you can type a file name in the Share Name dialogue box.

Select an Access Type. Your choices are Read Only, Full, and Depends on Password. Read Only means people on other computers will only be able to read files in the shared directory. They cannot edit them or save to the folder. Full means they can open, and change files in the folder, or create and save them there. Depends on Password allows you to specify a password that allows users Read Only Access, and a different password for Full Access. Your choice depends on how much security you want on your files.

I strongly recommend setting some password protection even if you feel you don't need it. Some viruses attack network shares that aren't password protected.

Once you select a password, you'll be asked to confirm it:



After confirming it, click Ok, and that's it!

Printer sharing is similar, except that you right click the Printer you want to share instead of the folder. You can get to your printers by going to Start, Settings, and clicking on Printers.

Windows XP File and Printer Sharing
**Please note, I made this tutorial on an XP Professional system. If your screens are different, or if my procedures are innaccurate for XP Home (they're slightly different), please reply to this post, or start a new post.

I believe File and Printer Sharing are on by default wit XP Home, so you can go straight to sharing a folder.

Double click My Computer (you may have to go to Start, then click on My Computer (if you want, you can right click on My Computer in the menu and select Show on Desktop)), then double click on your C: Drive to see all of your folders. Right click on a folder you want to share. Select Sharing and Security from the menu that comes up.



To check or change permissions, click the Permissions button on the Sharing tab of the folder Properties that opens up.



You'll see that the default is for all users to have Read Only permissions. This may be acceptable, but if you want to change the rights, you may do so. Click Ok and you're set.

For Windows XP, you may also have to permit traffic through your firewall (assuming you have XP Service Pack 2 installed, or have enabled the XP firewall).

Go to Start, Control Panel, and in Control Panel, double click Add or Remove Programs.



Click Add/Remove Windows Components on the left of the Add or Remove a Program window.

In the Windows Components Wizard, scroll down to Networking Services, high light it by clicking on it, then click the Details button.



In the Networking Services window that opens, click the box next to Peer-to-Peer, then click Ok, and Ok again. This should set your firewall to allow Peer-to-Peer networking.

misguidedyouth
May 28th, 2006, 12:34 AM
First lets start with Simple, unencrypted Wireless Networking for WinXP
Required components:
- Windows XP (Pro or Home)
- Wireless Network Interface Card (NIC)
- Wireless Router, Hub, or some other type of Wireless Access Point

Wireless NICs (commonly also referred to as "wireless cards") come in varying styles. The most often used are PCMCIA (usually used in laptops), USB and PCI. The installation is out of the scope of this article, so I won't cover that right now.
Now for the easy part - actually configuring your wireless network.

Access your router configuration and there will be a wireless configuration area. On most, wireless is enabled by default, but in case it isn't, go to the wireless configuration and assure that "Wireless" (may be different on yours) is set to "Enabled". There should also be an option to set the "SSID". This is a unique identifier for your wireless network, so set it to something you'll remember.

Now, on your computer (I assume Windows XP right now) go to Start->Control Panel (you may need to go to Settings->Control Panel depending on your setup). Click on "Network and Internet Connections" (if you don't see it, skip this step), and now go to "Network Connections".
Right-click on "Wireless Connection" (if you don't see it, please start a new post to resolve this problem first) and select "View available wireless networks". When the list finishes populating, you should see a network with your particular SSID. Click it, check the box that says "Allow me to connect to a network although it is not secured" and click "Connect".
You're done!

Encrypting wireless networks using WEP and Windows XP
Required components:
- Windows XP (Pro or Home)
- Wireless Network Interface Card (NIC)
- Wireless Router, Hub, or some other type of Wireless Access Point

Wireless NICs (commonly also referred to as "wireless cards") come in varying styles. The most often used are PCMCIA (usually used in laptops), USB and PCI. The installation is out of the scope of this article, so we won't cover that right now.


Now for the easy part - actually configuring your WEP secured wireless network.

Access your router configuration and there will be a wireless configuration area. On most, wireless is enabled by default, but in case it isn't, go to the wireless configuration and assure that "Wireless" (may be different on yours) is set to "Enabled". There should also be an option to set the "SSID". This is a unique identifier for your wireless network, so set it to something you'll remember. Now, look for "Wireless Security". You'll want to set this to "WEP", and a new menu should now be available. There will likely be a box that reads "Key Select" (again, may be different) that you'll want to set to "Key 1". There should also be several text boxes with drop-down menus beside/around them. In the first, enter a unique combination of characters, and specify the encryption bitrate following the chart below (again, this may vary depending on your router, but these are usually the defaults. Read your router docs for more information):
- 5 numbers = 64-bit
- 13 numbers = 128 bit
- 29 numbers = 256 bit

Now write down this number or remember it. This is essentially a "password" for accessing your network. Now, apply/save these settings and close the window.

Now, on your computer (I assume Windows XP right now) go to Start->Control Panel (you may need to go to Settings->Control Panel depending on your setup). Click on "Network and Internet Connections" (if you don't see it, skip this step), and now go to "Network Connections".

Right-click on "Wireless Connection" (if you don't see it, please start a new post to resolve this problem first) and select "View available wireless networks". When the list finishes populating, you should see a network with your particular SSID. Click the network, and there should be a prompt avaiable to input your WEP Key - this is the number we just wrote down. Enter it in this box, and click "Connect".
You're done!

Encrypting wireless networks using WPA and Windows XP
Required components:
- Windows XP (Pro or Home)
- Wireless Network Interface Card (NIC)
- Wireless Router, Hub, or some other type of Wireless Access Point

Wireless NICs (commonly also referred to as "wireless cards") come in varying styles. The most often used are PCMCIA (usually used in laptops), USB and PCI. The installation is out of the scope of this article, so I won't cover that right now.


Now for the easy part - actually configuring your WPA secured wireless network.

Access your router configuration and there will be a wireless configuration area. On most, wireless is enabled by default, but in case it isn't, go to the wireless configuration and assure that "Wireless" (may be different on yours) is set to "Enabled". There should also be an option to set the "SSID". This is a unique identifier for your wireless network, so set it to something you'll remember. Now, look for "Wireless Security". You'll want to set this to "WPA", and a new menu should now be available. There will likely be a box that reads "WPA Shared Key" (or something similar). In here, enter a number 8 to 63 characters long. Now write down this number or remember it. This is essentially a "password" for accessing your network. There may also be a box that says something similar to "WPA Re-Key interval". A setting for this around 3600 is safe. Now, apply/save these settings and close the window.

Now, on your computer (I assume Windows XP right now) go to Start->Control Panel (you may need to go to Settings->Control Panel depending on your setup). Click on "Network and Internet Connections" (if you don't see it, skip this step), and now go to "Network Connections".

Right-click on "Wireless Connection" (if you don't see it, please start a new post to resolve this problem first) and select "View available wireless networks". When the list finishes populating, you should see a network with your particular SSID. Click the network, and there should be a prompt avaiable to input your WEP Key - this is the number we just wrote down. Enter it in this box, and click "Connect".
You're done!

Instructions for Win2k and below:

The instructions for these, unfortunately, cannot be combined herein because of the nature of the available wireless devices and their configurations. A few pointers though (and you can always ask here for help):
- be sure to install all software that comes with wireless adapter.
- configuration will usually be similar to Windows XP in verbiage used.

WARNING - WARNING - WARNING
If at all possible, it is much better to use WPA instead of WEP as it is much more secure.

lalit_nashier
June 5th, 2006, 04:46 PM
पूरी िकताब छाप दी डाकी :eek: :eek: :D :D ;) ;) :p ,,,,,,,,,,,,,,


cheers...................

cooljat
June 5th, 2006, 05:04 PM
Great info Bro

rock on
Jit

lalit_nashier
June 5th, 2006, 05:15 PM
great info धन्यवाद

cheers...........

sukhdev
August 1st, 2006, 04:31 PM
thanks yar bhout kuch bata diya.
thats very important for newer
thankx

sunitahooda
August 1st, 2006, 04:41 PM
Ravinder....i must thank you for posting this info, it may be basic or you can say useless for most of the members but for a computer illiterate like me its very useful, i'll read it thoroughly after 3rd August, please keep posting such info.....i'll see if i get the tears in the last:)

rajeshrathee
August 1st, 2006, 06:21 PM
thanx bro
i needed this information
regards

misguidedyouth
August 4th, 2006, 01:40 AM
Ravinder....i must thank you for posting this info, it may be basic or you can say useless for most of the members but for a computer illiterate like me its very useful, i'll read it thoroughly after 3rd August, please keep posting such info.....i'll see if i get the tears in the last:)

i'll b delighted if i can send some stuff usefull for someone... well for any IT related stuff ... and before wasting ur time on googling... just give a try to this useless bro.