Tom's Hardware and Que Publishing are partnering up to give you four chapters from Scott Mueller's Upgrading And Repairing PCs, 20th Edition. This forth installment is a continuation of the third chapter we're making available from Scott's book, which covers Local Area Network (LAN) hardware and assembly. Don't forget to check out the previous chapters published on Tom's Hardware, Computer History 101: The Development Of The PC, Hard Drives 101: Magnetic Storage and LAN 101: Networking Basics. In the days to come, we'll also present a comprehensive look at Power Supplies.
The choice of a data-link protocol affects the network hardware you choose. Because the various flavors of Ethernet and other data-link protocols use different hardware, you must select the architecture before you can select appropriate hardware, including NICs, cables, and switches.
NICs for Wired Ethernet Networks
On most computers, a wired Ethernet network adapter is integrated into the motherboard. If the integrated component fails or is not fast enough, a replacement NIC can be added through the PCI or PCI Express slot (desktop computers), USB, CardBus PC Card (PCMCIA), or ExpressCard slot on a laptop.
Network adapters (both wired and wireless) have unique hardware addresses coded into their firmware. The hardware address is known as the MAC address. You can see the MAC address on a label on the side of the adapter, or you can view it after the adapter is installed with an OS utility such as the Windows ipconfig.exe command. The data-link layer protocol uses these addresses to identify the other systems on the network. A packet gets to the correct destination because its data-link layer protocol header contains the hardware addresses of both the sending and receiving systems.
Most motherboards have wired Ethernet adapters built-in, whereas discrete Ethernet network adapters range in price from less than $10 for client adapters to more than $100 for single or multiport server-optimized adapters.
Although you can connect two computers directly to each other via their Ethernet ports with a crossover cable, larger networks need a switch, which is frequently incorporated into a router. The network runs at the speed of the slowest component, so if you use a switch that runs at a slower speed than the network clients, the clients connected to that switch will run at that slower speed. Many wireless routers now include 1000 Mb/s gigabit Ethernet ports instead of slower 100 Mb/s Fast Ethernet ports.
When connecting systems on wired Ethernet networks, the following sections contain my recommendations on the features you need.
Speed
Your NIC should run at the maximum speed you want your network to support. Most gigabit Ethernet and Fast Ethernet cards also support slower speeds, meaning, for example, that a 1000 Mb/s (gigabit Ethernet) card also supports 100 Mb/s (Fast Ethernet) speed or standard Ethernet’s 10 Mb/s speed, allowing the same card to be used on both older and newer portions of the network. To verify multispeed operation, look for network cards identified as 10/100 or 10/100/1000 Ethernet. All modern Fast or gigabit NICs should also support full-duplex operation:
- Half-duplex means that the network card can only send or only receive data in a single operation.
- Full-duplex means that the network card can both receive and send simultaneously. Full-duplex options boost network speed if switches are used in place of hubs. For example, 1000 Mb/s gigabit Ethernet cards running in full-duplex mode have a maximum true throughput of 2000 Mb/s, with half going in each direction.
Note: Unlike hubs, which broadcast data packets to all computers connected to them, switches create a direct connection between the sending and receiving computers. Therefore, switches provide faster performance than hubs; most switches also support full-duplex operation, doubling the rated speed of the network when full-duplex network cards are used.
For more information about switches, see Scott Mueller's Upgrading And Repairing PCs, 20th Edition, “Switches for Ethernet Networks,” p. 816 (this chapter).
Bus Type
If you need to install a network adapter for use with a gigabit Ethernet (10/100/1000 Mb/s) network, any of the following buses have more than adequate performance:
- PCI/PCIe. The integrated NIC built in to most motherboards are either PCI or PCIe devices.
- CardBus/ExpressCard (laptop computers).
All of these buses support gigabit Ethernet adapters without limiting throughput. Integrated network adapters use either the PCI or PCI Express bus to connect to the system, both of which have more than enough bandwidth. Note that USB 2.0 (480 Mb/s) is not on that list because it is simply not fast enough to fully support gigabit Ethernet’s 1000 Mb/s bandwidth; however, 100 Mb/s Ethernet connections will work on USB 2.0 with no problems. USB 3.0 would be more than fast enough to support a gigabit Ethernet adapter, however there aren’t any network adapters I know of using USB 3.0.
How about a copy for each of the users who make the top ranks for the month of November ... under the Hardware sections of the forums?
I got talked into making 10...
Oh I don't know. I have made several thousand patch cord over the past 18 years.
All you need is a high quality crimper, good cutters and small screw driver. You are set.
Anyway. As I said, I think it's well written and probably quite suitable for people who don't know anything about networks (except it seems to assume people know the osi model). I'll go see if the other chapters are equaly basic.
5 MBps = 40 Mbps... so it's not that weird. xD
Heya Reynod,
We had access to 10 copies of it for a contest that ran with the first few pieces of the book, but those were given away already.
I agree that it's a great idea to reward the most active forum users, though. I'll get together with Joe and see if there's anything we can do there!
Have a great weekend,
Chris
I feel a bit stupid now I missed it.
It would be great if you could do something again though.
I did PM Don Saturday to ask him.
Cheers
There is no "amount" it does have a shield.
it was first thought that shielding the cable from external interference was the best way to reduce interference and provide for greater transmission speeds. However, it was discovered that twisting the pairs of wires is a more effective way to prevent interference
No. Shielding is better. But the trick on twisting is that we are talking about "differential" signals. If not, twisting would be useless. Twisting to cables cancel each others emissions and emissions from other places to the cable are canceled too.
10GBE pros say you should not wire UTP but only STP.
Need cable lengths longer than the lengths you can buy preassembled
Never buy preassembled cables. Can't assemble cable as I said before on mono-filament cable.
One filament wires can't be twisted or take turns or >90 degrees. There's a big chance they can break. Can't wire thru a pipes with the RJ45 plug on it.
Use Jacks. Buy machine assembled/tested multi-filament patch cords from the jack to the computer/router/printer/switch, whatever.
First off, as a disclaimer, I didn't bother reading the wireless section. Stuff has been changing too rapidly the past few years to even bother, and it is ultimately so simple nowadays that you shouldn't even have to bother with the wireles options. What I did see of wireless information (such as range) was horribly inaccurate. In my experience with most indoor environments, you'll be lucky if you get a *reliable* signal at a fraction of the 150 feet he mentions.
Simple advice for wireless: Buy a dual-radio N-capable wireless router and then decide if you're going to use N-capable internal wireless cards or USB dongles for any devices you have that do not include integrated wireless. Be warned that in my experience, many wireless routers designed for home use work fine for wireless devices accessing the internet, but when attempting to transfer data between a wired and wireless device, the router will act as a bottleneck, often running at speeds lower than what standard (10 Mbps) ethernet will provide. If you plan on hooking up a device such as a home server or NAS device to your home wireless router, be careful what you pick and either fork out the money for a higher-end SOHO/SMB device or read your reviews thoroughly and ensure that you're getting exactly that device (down to the revision number even, sometimes).
This article clutters the users mind with unnecessary information and technical details which to knowledgeable persons will already be apparent, and recognized as often incorrect; and for the unknowegeable reader - incorrect and irrelevant but taken as true. To rattle off a few
-switches and hubs, while sharing some features (they're small, blockish and have multiple ports) are also different at an operational level - switches are OSI layer 2 devices, while hubs are electrical devices operating at OSI layer 1.
-Packets do not get where they need to go because of MAC addresses; frames get where they need to go thanks to MAC addresses while packets are at OSI layer 3 and utilize IP addresses for routing.
-If you want to see your MAC address via ipconfig, use ipconfig/all. ipconfig on its own will not provide you with this information.
If I wanted to take a closer read or go through it again, I'm sure I could pull out atleast as many errors as I listed above, but I've gotten enough of my steam out about someone publishing yet more outdated and erroneous technical info or advice in the realm of networking and IT. Please, if you're going to write a tech article, do it with a purpose, stay true to it, make sure you have your stuff down pat, and damn well update it if you're going to re-publish it.
No one cares about coaxial ethernet anymore, unless you're over the hill or working in some industrial environment with networked machinery, in which case I hope you're not getting your expertise from this article.
PS. I'd still like to say thanks to Tom's Hardware and that they're an invaluable resource - not just for their reviews and articles, but for the user community they have generated as well. But with that said - is it just me, or is Tom's IT site just one big stream of advertisements in the guise of articles, news stories, and white papers?