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Mussels
05-11-2007, 11:14 AM
[page=Introduction]
Introduction

Almost everyone has a home network these days, whether they realise it or not. From a short Ethernet cable to your modem or a wireless network to your laptop, networks are quite common in the average home. The purpose of this guide is to explain as simply as possible, the basics of PC networking, and a few pitfalls to avoid. For a start, I’ll list the most common networks in todays homes.

Speed
Network speeds are measured in Megabits (Mb) as opposed to say, hard drive and memory speeds, which are Megabytes (MB). It takes 8Mb to make one MB. This is why you may have 1 Mega*bit* internet, but your internet download speeds fall far short of one Mega*byte* per second.

Ethernet
This is cabled networking. Often the cable is blue, but other colours make an appearance too. The two most common speeds are 100Mb (one hundred Megabit) and 1000Mb (one thousand megabits, or Gigabit). Both of these use the same kind of cable, but older, cheaper cables may hamper gigabit speed down to 100Mb levels.

Wireless (aka Wi-fi)
Especially in America, wireless hotspots are increasingly popular. Wi-fi is mostly used for laptops, as it doesn’t need any form of cable to connect. Common Wi-fi speeds are 11Mb (802.11b) and 55Mb (802.11G). Some router/Wi-fi combos support up to 108Mb. Most 802.11g devices support 802.11b as a fallback, in case not all your devices are capable of running at the higher speed.

802.11n is an up-coming high-speed wireless network, intending to be the gigabit equivalent in wireless networking. I will add more on this later; wireless N products are still extremely rare.

Wi-fi is slower than cabled Ethernet but can be cheaper if you have a large house, or if the phone line for the modem/router is not located near your PC.



Please note that the speed at which you connect to the router does not affect your internet at all - be it 55Mb wireless or 1000Mb wired; most internet connections around the world are less than 1Mb, and very rarely go above 10Mb. The speeds reported in windows are the network speed, and NOT your internet speed - to find out your internet speed, contact your ISP or use a speed test from the following link (Please choose one in your country)
Google Speed test (http://www.google.com/search?hl=en&q=speed+test)


http://www.techpowerup.com/articles/147/images/networking.jpg
Clockwise, this equipment is a 5 port Ethernet switch, a wireless capable router, desktop Gigabit Ethernet card and finally a a Laptop Wireless networking card.


[page=Wired setup]
Basic wired setup guide


We'll start with a cabled setup.

To use this kind of connection, you will need to have the following:
A modem, router, or switch with a free Ethernet port, a suitable Ethernet cable (100Mb or gigabit certified) and an Ethernet LAN card in your PC.

Attached are some images of my router, and a 5 port ethernet switch.
http://www.techpowerup.com/articles/147/images/router-front.jpg
The front view.

http://www.techpowerup.com/articles/147/images/ethernet.jpg
Rear view. Note the router has an aerial for 55Mb Wi-fi, 4x ethernet ports, and a USB connection.
Also note the blue ethernet cable linking the two.


Assuming your network is already functional, connecting to your PC should be as simple as plugging the cable in to your network card, waiting a minute and then you're good to go.

Different Ethernet devices can connect together. This is called up-linking. In my home router setup, I have the following hardware:

Wireless router
Gigabit switch
3 Wired PCs
One wireless laptop


In this setup, the router runs a single cable to the gigabit switch, and my PCs connect to the gigabit switch. This allows the PCs to have high speed access to each other, and 100Mb access to the router (and therefore the internet). The laptop accesses directly via the wireless, but can still connect to the desktop systems for gaming and file sharing.


Some good hints:
Never connect more than one cable between devices - it won't make it faster, and may slow down or 'break' the network. (Example: If your PC has two network cards, connecting two cables to your router will not make anything faster.)

Some motherboards come with dual network cards, and support a feature called NIC teaming. This feature is explained in more detail in the 'Advanced networking' page of this article.

Shorter cable lengths are better. While an extra meter wont make much of a difference, an extra ten metres of wasted length could cause problems with electrical interference. Try and get cables as short as possible.

Cables are a trip hazard - if they have to run more than a meter or so, try running them along walls, above door frames, and so on. Professionally installed cables are a good idea, but if you can make it safer yourself, do so.

Cat5e is the standard for modern 100Mb cables; Cat6 is the preferred type for gigabit. However cat5e cables will easily handle gigabit speeds for short distances, so there is no need for the more expensive Cat6 unless you're running it more than 20 Meters or so.



[page=Wireless Networks]
Wireless networks.


Required hardware:

Wireless router (Or Wireless access point, also called a WAP)
Wireless network card


http://www.techpowerup.com/articles/147/images/wireless-router.jpg
A Wireless router (note the aerial)
http://www.techpowerup.com/articles/147/images/pcmcia.jpg
Laptop Wireless card - Some laptops have them internally.

Wireless (Wi-fi) setups work very similar to wired, except that instead of connecting via a cable, it uses radio transmissions in the 2.4Ghz range - the same as Bluetooth accessories for mobile phones, and some cordless landline phones.

The setup for a Wi-fi network may differ depending on the network card you own, but is usually a variation of the following:

Scan for wireless networks
Choose the network you wish to join (You could access your neighbor's network, for example)
Enter any password/keycodes required (this depends if your wireless network has security enabled)
Enjoy your wireless connection



Many people buy wireless routers without using the wireless features. These people should read the router's manual and disable the wireless - it is a hacking risk, and there is no use having it enabled if you don't use it.

Some people also don't use encryption, mistakenly thinking "why would anyone hack MY internet?" Think of your neighbours or anyone within 200m of your house; they can easily leech off your connection [note to muss: assuming this is what you mean? or something in there that says what you mean]. I myself have walked around town with my laptop, and I have used other people's internet hundreds of metres from their homes. You should always enable security, even if it's just to stop passers-by from accessing your network.

Notes on Wi-fi hacking/encryption
WPA and WPA2 are the best encryption methods if your hardware supports it. Experts using Linux can hack a WEP 64 or WEP 128 code in less than 15 minutes, and gain access to your network.

Someone who gains access to your network doesn’t just get the internet - they are on your NETWORK, exactly the same as if they came in and plugged a cable into your router. If you have shared files and folders over the network, they CAN access these, and depending on how you set them up, possibly even delete those files.

These people CANNOT access files you have not shared, however. If you use a wireless network, think ahead and only share files when you want them accessed, and un-share them when done.

Advanced security options and methods to make wireless networks more secure will be expanded upon in a future revision to this article.


[page=Boost a wireless signal]
Boost a wireless signal
The most annoying thing about wireless is getting dropouts and disconnections in the middle of using the network, such as during gaming or downloading a file.

This page will cover some good tips and tricks to help you out.

Most wireless cards these days come with two things: an indication of speed, and an indication of signal strength. They are generally linked, as lower strength signals drop in speed to become more reliable.
Speed, as previously mentioned, is 11Mb, 55Mb or 108Mb by default, but when your signal weakens it drops by stages; a weak 55Mb signal may change to 24Mb or 36Mb, and an extremely weak signal could drop to 1-2Mb. Signal strength in windows is usually 5 bars, 1 for bad, 5 for excellent - this is simple enough to now if any tweaks have helped you.

On to the tweaks!

The first one is simple; it's all about positioning. Where are your PC and router located? If your router is locked away in the closet, any doors or walls in the way will hamper your signal. The best place is to have it relatively high off the ground, with as few walls/obstacles near it as possible.

Aerial polarity: 90% of desktop wireless cards and routers have an external aerial, which can be rotated in a circle. It is important that both your PC and your router's aerial face the same way - this simple tweak can give you a good 50% boost in some circumstances, especially if there is a height difference between the two (such as cases where the router is in the attic/on a higher floor).

Finally, you could always replace the aerial!
http://www.techpowerup.com/articles/147/images/wifi.jpg
This here is a PCI wireless card for a desktop, with the stock aerial removed. The original aerial was a 2dB (decibel) aerial about half the height of the thick black one in the image - the one in the image is an upgraded 5dB aerial. The thin black aerial is a 7dB aerial, with an extension cord attached.
In theory, going from a 2dB aerial to a 5dB aerial, you gain 3x more sensitivity - going to the 7dB aerial is 5 times stronger than the original.

While these aerials are not free, if you upgrade both devices (router and PC, like I have) then you can extend your network to incredible distances; I've used my laptop 150 meters away from my house, with a 'strong' connection. The ability of the 7dB aerial to move around is also a bonus, as you can place the aerial on top of the PC or monitor, and improve the signal that way.

[page=Advanced networking features]
Advanced networking features
As mentioned on the previous pages, there are extra features on some network cards/operating systems that may be of use to people.

I will list a few of them, mentioning the associated pros and cons.

Gigabit Networking
This one may seem obvious, but there are many myths surrounding gigabit. Running a gigabit network can, in theory, give you 10x the bandwidth of a 100Mb network, but in reality this isnt true. Speeds of 300-400Mb are more common due to a few of the following factors.

PCI cards
If your gigabit card runs on PCI, then it is sharing bandwidth with the rest of the system - fighting for the bandwidth.
Cabling/distance
Longer distance and/or poor cables can easily reduce the network speed.
Switches/hubs
Even brand name gigabit equipment can let you down, providing less than full speed.
Hard drives
The average hard drive (400GB and up) can only just push 70MB/s, perhaps 50MB/s sustained - Gigabit is 125MB/s! You'd need fast drives on BOTH ends of the network, perhaps even in RAID, to get full gigabit speed.

Another common myth is that gigabit makes 'everything' faster; this is not true. Gigabit only has a bandwidth advantage and not ping (gaming) or reliability. Only go gigabit if you move large files across your network regularly as it serves no purpose otherwise.

'NIC teaming"
NIC teaming means allowing two on-board network cards to connect to the same network, and theoretically get double the speed.

True story: very few setups can even max out a single connection, let alone two - the speed of your system's hard drives is rarely fast enough to power a single gigabit link, let alone two. Best ignored for most users.

Network bridging
A feature offered in most flavours of Windows, and a way to get around not having a router.

Example:
Example: Let's assume you have a dial up internet connection, and want to share it between two PCs. IF you activate bridging in Windows network controls, your PC takes the role of a router and shares it over another network. Your dial up comes in, is shared over the network you choose (wired or wireless) and any other PCs on the network can connect to your PC just like a router - effectively sharing the internet.

True story:
Network bridging can be handy if you don't have a router, but it has its flaws:
There is no way to use port forwarding, so some applications (games) may not work
It turns your network card into a DHCP server, so all other systems have to obtain IP addresses from that PC
Because the PC becomes a DHCP server, the network goes down if your PC turns off - not pleasant for other users of the network.



Direct connecting - "Crossover"

Using crossover cables (typically red cables) to directly connect two machines eliminates the need to use a network switch (also called a hub) to connect with. This is also a way to connect two gigabit enabled computers at full speed, even if you only have a 100Mb switch.

In reality:
It's fast, especially once you take the extra link (the switch) out of the equation
Unless you're using network bridging, you will need to manually set IP addresses for all involved network cards.

Wireless networking - "Ad Hoc" mode
Ad hoc mode is a method by which wireless network users (such as say, two or three laptop users) can directly connect to each other without needing to use a central networking point, such as a router or wireless access point.

In reality:
Ad hoc mode should only be used if you have no other options, or for short term use as it can be difficult to set up, and is quite insecure (any wireless users may join this network, and potentially access your shared files).

[page=Conclusion (Temporary)]
Final notes

Obviously this guide is a work in progress, as it is only intended to introduce you to the concepts of networking, and the differences between wired and wireless connections.

I will definitely expand upon this, with short guides for common problems.

Upcoming additions will be:

How to manually set an IP address
How to determine your network IP address
Techniques for making Wireless networks safer
Networking tips for windows Vista

If there is anything else you would like to see added in upcoming revisions, please leave a comment and I will attempt to add it in.

I am also open to people asking questions about their hardware setups, and cable routing - if it concerns you, it may be worth adding to this guide.

Mussels
05-11-2007, 11:15 AM
Note: This will eventually go up as an article here on TPU, and will be removed from this section. Wizzard asked me to put it here, since i dont have permission to use the normal review sections yet.

Comments are welcome, but bear in mind this thread and all its comments may be deleted when it is moved.

DanTheBanjoman
05-11-2007, 11:28 AM
(Example: If your PC has two network cards, connecting two cables to your router will not make anything faster.)

NIC teaming ftw, link aggregation is the RAID0 of networks.

Also cat5e can handle Gbit already. Plus long cables not only are a waste, if you roll up the extra length you can actually hurt performance since you're creating a spool.

Mussels
05-11-2007, 11:49 AM
NIC teaming is quite pointless, unless its on BOTH ends. This is about basics, people who say, connect to a 100Mb router twice thinking it doubles internet speed, or someone connecting their router twice to their switch thinking it gives double bandwidth.

I may clarify this more in a reivsion.

Wile E
05-11-2007, 12:05 PM
You left out 802.11N, well Draft N, or what ever the hell it's called now. lol

Mussels
05-11-2007, 12:08 PM
I think i need to note here - this is a work in progress, and its about tech people have NOW.

I will be more focusing this on smaller guides compiled together, such as setting up wifi under vista compared to XP, things like that. How many people have 802.11n in their homes today? and of that small number, how many forked out the extra without knowing how to set it up in the first place?

Trying to do the most 'good' with limited time ;)

Wile E
05-11-2007, 12:11 PM
I just brought it up because you're seeing more and more of them on the shelves. Heck, my iMac has it from the factory. Good article, btw.

Mussels
05-11-2007, 12:15 PM
I just brought it up because you're seeing more and more of them on the shelves. Heck, my iMac has it from the factory. Good article, btw.


Thanks, i had a friend (female, non-technical) asking me lots of questions about wireless, so originally i was just writing this up for her.

Wireless-N will probably get its own page later, as i dont own any N products i dont want to post any incorrect information on it just yet.

DanTheBanjoman
05-11-2007, 12:44 PM
NIC teaming is quite pointless, unless its on BOTH ends. This is about basics, people who say, connect to a 100Mb router twice thinking it doubles internet speed, or someone connecting their router twice to their switch thinking it gives double bandwidth.

I may clarify this more in a reivsion.

Actually, NIC teaming is handy when connecting directly. ie via 2 crosscables. Nowadays quite some mobos come with dual Gbit, link them.

Mussels
05-11-2007, 12:47 PM
Actually, NIC teaming is handy when connecting directly. ie via 2 crosscables. Nowadays quite some mobos come with dual Gbit, link them.

I updated and changed that section, but truly, can you even max out a gigabit link without running RAID? i barely get 400Mb/s on my home network, 600Mb when i had RAID.


Edit: theres been quite a few updates now, so before anyone comments further, please check those updates.

Mussels
05-19-2007, 12:26 PM
Update: several pages added, and a wonderful girl by the name of L helped me fix various spelling/grammar mistakes.

Article should be much nicer to read now :)

ex_reven
05-19-2007, 12:30 PM
Nice article man. Very good to read over.

Clear cut and concise. Excellent.

Mussels
05-19-2007, 01:15 PM
thanks, ex-reven.

More updates now, as w1zz explained a few forum codes to me (dot points, etc)

theonetruewill
06-02-2007, 01:44 PM
Nice concise guide Mussels.
Can I give a suggestion? A small guide on how to share files between computer's securely on a wireless network perhaps. I've got plenty of neighbours who have failed to do this, so it might be a useful addition.

DanTheBanjoman
06-02-2007, 02:08 PM
I think you're mixing up hardware and software, for example the crossover section. Setting an IP manually has nothing to do with how the wires are connected. In fact, you don't even have to use TCP/IP, and DHCP works perfectly fine via a crosscable as well.

Dippyskoodlez
06-02-2007, 02:59 PM
A cool trick mac related that saved my butt a few times, you can enable sharing your NIC via wireless and turn your computer into a mini router... I have yet to be successful duplicating this with windows though.

Also, Ethernet pinout?(I.E. Crossover Vs Patch) Cables are often color coded if you buy them from maybe belkin or blackbox, but a majority aren't. Making your own is also trivial. You also need to note the differences between a ROUTER, a SWITCH, and HUB.

They are quite significant when developing ones home network.

Its not important, but there is a "ethernet over phone" type thing, its a pile of crap, but does "work".. but fiber should atleast get a mention ;D

Wile E
06-03-2007, 08:42 AM
A cool trick mac related that saved my butt a few times, you can enable sharing your NIC via wireless and turn your computer into a mini router... I have yet to be successful duplicating this with windows though.
You can do it in Windows with the Network Setup Wizard, Dip.

Mussels
06-03-2007, 01:42 PM
A cool trick mac related that saved my butt a few times, you can enable sharing your NIC via wireless and turn your computer into a mini router... I have yet to be successful duplicating this with windows though.

That feature depends on the wireless card, and you could mean two things.

#1 - windows ICS (internet connection sharing) over your wireless network card, using ad hoc mode

#2 Some wireless cards have an AP (access point) feature, so that they work in normal (Infrastructure mode) for other PC's to connect to that network.

For your mac - i assume its #2, as macs quite love to throw good hardware in, then pretend its an advantage of the operating system.

Mussels
06-03-2007, 01:43 PM
Nice concise guide Mussels.
Can I give a suggestion? A small guide on how to share files between computer's securely on a wireless network perhaps. I've got plenty of neighbours who have failed to do this, so it might be a useful addition.

I'll be adding a small page on doing this in windows vista soon, since XP is the same with a step or two less, i assume people will figure it out.

Dippyskoodlez
06-03-2007, 02:03 PM
That feature depends on the wireless card, and you could mean two things.

#1 - windows ICS (internet connection sharing) over your wireless network card, using ad hoc mode

#2 Some wireless cards have an AP (access point) feature, so that they work in normal (Infrastructure mode) for other PC's to connect to that network.

For your mac - i assume its #2, as macs quite love to throw good hardware in, then pretend its an advantage of the operating system.

I had just never been able to get the wireless card to show up as an AP for other computers. (Not saying its impossible)

OS X you just hit share, and BAM, every other computer thinks its a wireless router. This works on -every- mac. ;)

I would really like to see how to do this in windows as effectivly, as my modem+router is a pile of crap!

Mussels
06-03-2007, 02:07 PM
Its a little more complex on PC, but look up internet connection sharing. I don't have the same hardware as you so i cant test it but it should be fairly straight forward.

#1 - tell XP to share the ethernet port, should auto-share over the other networks (giving out DHCP addresses)

#2 - set other PC's to search ad-hoc channels, not just infrastructure (macs may automatically do this)

P.S - XP and vista have an option to set the order of networking cards - its under the advanced menu. Its possible you will have to change the order to set the ethernet to #1, as i beleive wireless takes that position by default. In XP, right click network places, click properties then go into the advanced menu and select advanced options. Change the order using the up/down arrows.

Dippyskoodlez
06-03-2007, 03:41 PM
Its a little more complex on PC, but look up internet connection sharing. I don't have the same hardware as you so i cant test it but it should be fairly straight forward.

#1 - tell XP to share the ethernet port, should auto-share over the other networks (giving out DHCP addresses)

#2 - set other PC's to search ad-hoc channels, not just infrastructure (macs may automatically do this)

P.S - XP and vista have an option to set the order of networking cards - its under the advanced menu. Its possible you will have to change the order to set the ethernet to #1, as i beleive wireless takes that position by default. In XP, right click network places, click properties then go into the advanced menu and select advanced options. Change the order using the up/down arrows.


Hm. how do you set the WEP? :)

Urlyin
06-08-2007, 04:05 PM
NIC teaming ftw, link aggregation is the RAID0 of networks.

Also cat5e can handle Gbit already. Plus long cables not only are a waste, if you roll up the extra length you can actually hurt performance since you're creating a spool.

more of a chance the bytes will fall out onto the floor ... lost forever :p

Namslas90
06-08-2007, 04:29 PM
Plus long cables not only are a waste, if you roll up the extra length you can actually hurt performance since you're creating a spool.


Close; the problem is actually that when an intenet connection cable is "spooled" or "coiled" it creates an additional "inductive EMF"(electo-magnetic field) that contradicts (works against) the inductive field in the cable normally. This inductive field slows down the wires ability to transfer data at high rates of speed. There is also a small increase in resistance, but this is not as much a problem with the newer cables. The reason this occurs is that newer cables(cat 5E and ^) have their "paired" wires twisted, thus creating an inductive field to help propell the data down the line. Adding a "coll" or "spool" contradicts this first inductive field and works against it, thus slowing down the data transfer rate, and reducing overall performance.

:toast:

Pinchy
01-21-2008, 12:19 PM
Nice article Mussels.

Just one thing, when you say it is rare for internet to be above 10Mb....

I'm not sure about other countries, but here is Aus (as you should know) we have cable which is a standard 8Mb, then there is the cable extreme which is 30Mb as well as ADSL2 which is 24Mb.

Mussels
01-22-2008, 02:22 AM
this hasnt been updated for about a year, ADSl2+ is 22Mb at best.

Dont forget most of those speeds are 'at best' and rarely end up that fast.

Will update this eventually to add more modern speeds in, but keep in mind the small areas cable and ADSL2+ is available in in australia compared to ADSL.

Pinchy
01-22-2008, 05:38 AM
Woops. I forgot ive got the date format set to MM/DD/YYYY not DD/MM/YYYY.


(Thinking it was written on the 5th of November, not the 11th of May)

Mussels
01-22-2008, 05:40 AM
thats fine. just been so busy its hard to keep up with things like this... i'd have forgotten it were it not for email notifications.

zatblast
01-28-2008, 02:19 AM
ok not to be annoying... but the first image is bothing me due to the wording under it

"Clockwise, this equipment is a 5 port Ethernet switch, a wireless capable router, a Laptop Wireless networking card and finally a desktop Gigabit Ethernet card"

I seriously feel it should go:

"Clockwise, this equipment is a 5 port Ethernet switch, a wireless capable router, a desktop Gigabit Ethernet card, and finally a Laptop Wireless networking card"

changes were the placement of the desktop and laptop cards....

anyways sorry to point out the mistake... but if you didnt know what you were looking at (somehow) you could get really confused...

but like the article :)

Mussels
01-28-2008, 04:14 AM
ok not to be annoying... but the first image is bothing me due to the wording under it

"Clockwise, this equipment is a 5 port Ethernet switch, a wireless capable router, a Laptop Wireless networking card and finally a desktop Gigabit Ethernet card"

I seriously feel it should go:

"Clockwise, this equipment is a 5 port Ethernet switch, a wireless capable router, a desktop Gigabit Ethernet card, and finally a Laptop Wireless networking card"

changes were the placement of the desktop and laptop cards....

anyways sorry to point out the mistake... but if you didnt know what you were looking at (somehow) you could get really confused...

but like the article :)

made a mistake huh? woopsies.

-fixed. cant beleive no one (myself included) noticed that.