Hubs and Routers And Switches, Oh My! Hooking it All Together!
In this article I am going to talk about some of the different ways you can use hubs, switches and routers to hook a number of different computers together and connect them to the Internet. I am also going to inflict upon you a glossary of some of the popular networking/internet related terms and acronyms, to help you get a handle on what it is those geeks are actually talking about, or to help you sound like a geek at cocktail parties.
Glossary of Networking Terms
802.11x(a,b, g, and n
) IEEE 802.11x (add your letter where the x goes) is a set of standards for implementing wireless networks, proposed by the Institute of Electrical and Electronic Engineers
. Any wireless device you use today adheres to one of those 802.11xstandards. The additional letters are amendments to the standards, generally about when a higher speed wireless standard was developed (a is slow, n is fast is pretty much all you need tore member).
An older method of having a remote server assign internet information to your computer Bootp is somewhat more labor-intensive than DHCP, but is/was used by many larger institutions because bootp provides more control over who is allowed to connect to the internet on a large network.
Dynamic Host Configuration Protocol – a way by which a remote server can assign an IP address and other internet information to your computer without you having to manually enter in any information. Most commercial providers use DHCP now to assign IP addresses. To set up your computer for them, you simply tell it to use DHCP, and your provider’s DHCP server does the rest of the work.
Domain Name Servers At one time, in the deep dark distant past, computers connected to the Internet were only assigned IP numbers to identify them. This meant that if you wanted to connect to another computer, you needed to know its IP number. People found that this was very difficult to do, so they came up with Domain Name Servers, which are computers on a network which keep a list of IP numbers and a corresponding list of names that are assigned to those numbers.
A unique, 12 digit ID number assigned to the Ethernet card or adapter inside your computer. In some cases (such as in large institutions like universities), IP addresses are assigned to computers based on their Ethernet address, a process referred to as registering. Also referred to as a NIC (Network Interface Card) address or MAC address (not sure what the MAC part stands for, but it's NOT Macintosh!).
Internet Mail Access Protocol – a newer method of storing email on a mail server. If you are using an IMAP mail server, your email is stored on the server itself, and your email client just goes out and looks in your mailbox. Your mail never leaves the server. This means it works better for checking mail from multiple locations, and your mail is pretty safe if YOUR computer crashes, but your mailbox can fill up pretty quickly and if your email server crashes you can lose your mail. IMAP mail clients are a bit more complex to set up. All newer email programs support MAP.
Internet Protocol number, a unique number assigned to each computer connected to the Internet. Usually consists of four sets of three digit numbers, separated by dots (periods), i.e. 192.168.231.111. Some of these sets of numbers are reserved for special purposes. One of these is the192.168.xxx.xxx IP number range, which is reserved for private networks like you would find in a house or small business.
In the beginning of the Internet, we used the 12 digit IP number like described above, thinking that we would have enough possible numbers so that each device connected too the Internet could have a unique number. We were wrong. IP V.6
is a HUGE project to try to “renumber” the Internet so we don’t run out of numbers.
Internet Service Provider – The group or company that provides your connection to the Internet.
Local Area Network – a network contained within one room, one building or a small number of buildings.
Network Address Translation - NAT is a tool used inside routers to translate a number of different IP addresses on the INSIDE of your home network to ONE address outside your router (the IP address that identifies your entire home network on the internet). ISPs provide routers that use NAT in order to increase the security of your home network. Your router should contain what's called a NAT table, which can be used to map specific addresses within your network to that single address OUTSIDE your router, so that computers outside your network can access that machine.
POP (Def. 1)
Post Office Protocol – an older method of storing email on a mail server. POP-based email clients physically move your email from the mail server to your local hard drive when you check your mail, meaning that if you check your mail at home with a POP client, then try to check it on a different computer at work, you will not see any of the mail that you downloaded at home when you check your mail at work (unless you specifically tell your email client NOT to delete the mail from the server when it checks, but that can lead to an overfull email account or confusion between what mail is where). Some Service Providers only support POP mail on their servers, likely because it reduces the amount of mail on their servers and thereby their responsibility in the event of a server failure. POP mail clients are fairly easy to set up and run.
POP (Def. 2)
The sound your blood vessels make when you come back from a trip to South America and realize that you were checking your email on someone else’s computer there and you set it to use POP mail and all 3000 of your old email messages are on that computer, in South America.
The IP address of a router on your network. Your computer needs to know this in order to be able to talk to the router so the router can point it to the Internet. Sometimes known as the Default Gateway on PCs
Routers can be either pieces of hardware or a computer running special software. A Router is piece of hardware that creates two separate networks, and allows network or internet traffic to be sent and received (routed) between the two networks.
Service Set Identifier - An SSID is a 32 character long unique identifier assigned to your wireless access point, used for helping direct wireless traffic to the correct wireless access point. It differs from the name you assign to your wireless network IF you have a large, multi-access-point network. In that case, the SSID will direct the wireless traffic to the CORRECT access point in the larger network.
Simple Mail Transfer Protocol server – a fancy name for the computer your ISP uses to send mail. This is a piece of information that your email client will need, particularly if your email account is on an email server NOT managed by your ISP.
Another number used for identifying where a computer is located on a network. Most folks WON'T have to worry about Subnet Mask numbers in their homes, as most home networks are not large enough to have different "subnets".
Transmission Control Protocol/Internet Protocol, basically the language used by the Internet to enable computers to talk to each other
Wide Area Network – a network that spans relatively large geographical area.
Wired Equivalent Privacy, this was one of the first password protection setups for wireless access points. However, it was not particularly secure, and has been superseded in most cases by WPA and WPA2
Wi-Fi Protected Access - This is a newer way to password protect your access to your wireless network, it is more secure than WEP, but not supported by older wireless access points
A box provided by your Cable Company to give you access to the internet. The internet information is sent down the same wire as your Cable TV signal, the Cable Modem separates the TV signal from the internet information.
(DSL = Digital Subscriber Line). A box provided by your telephone Company to give you access to the internet. The internet information is sent down the same wire as your telephone signal, the DSL Modem separates the telephone signal from the internet information.
What’s the difference between DSL and Cable?
1. DSL has a cooler sounding name. 2. DSL signals are sent directly from the Telephone company to your house via your phone line, Cable signals are sent via the shared cable system. This can mean that your DSL signal is more reliable (you don’t have to share it with anyone who might be hogging the internet in your neighbourhood), BUT you may get higher speeds with a Cable modem (the technology allows for higher speeds).
Some Examples of Networking, Then and Now
Using a crossover cable is the simplest way to hook two machines with 10BaseTEthernet together. It is a specially wired cable that allows the machines to transmit and receive data from one another.
If you do not have a crossover cable, or you have more than two machines, the minimum requirement for hooking Ethernet-capable machines together is to use a hub.
If you intend to expand your network in the future, or connect your hub to another hub, a router or a cable modem, you will want to make sure that the hub you purchase has an uplink port. NOTE: This configuration WILL NOT allow you to use both machines on a high-speed Internet connection at the same time, unless your Internet Service Provider (ISP) has given you two IP addresses (one for each machine).
If you intend to use both your computers on a high-speed internet connection at the same time, without having to obtain a second IP address from your ISP, you will need to purchase a Cable/DSL Router. Essentially, on one side of a router is your home LAN (Local Area Network), on the other side of the router is the WAN (Wide Area Network), which usually comes out of the back of your cable modem or DSL Modem. The router assumes the IP address you were assigned by your ISP, and takes the responsibility for assigning unique IP addresses to the computers on your LAN
This is a less common configuration, used mostly by geeks who have a lot of older hardware that isn’t capable of using 10BaseT Ethernet. A repeater is simply a 10BaseT Ethernet hub that also has a 10Base2 connection on it and will bridge from one to the other.
This is a pretty rare configuration, but is the ultimate in geekness, and is used for hooking together 10BaseT, 10Base2 and LocalTalk computers and hardware. LocalTalk Bridge is a piece of software available from Apple (I don’t know for how much money) that will bridge from an Ethernet port to a LocalTalk port. It is useful if you have an older, AppleTalk-only printer that you want to use on your network, but means you have to have the computer that is running the bridging software turned on whenever you want to print to that printer. An alternative is to buy a localtalk to Ethernet adapter, like the Asante EtherPrint adapter (about $90). Note, that if you are using any localtalk bridging to connect older, Appletalk-only computers (i.e. Mac Plus or Mac SE), these machines will not be able to connect to the internet, because most of this bridging technology does not support TCP/IP (unless you are a real geek and know how to configure and run AppleTalk over MacIP. You gotta be an old Mac geek to know that one).
This is a typical setup for a home network today. Your ISP provides you with a Cable/DSL modem, and you provide a wireless router so that you can have a wireless network in your home.
Many ISPs are moving to a setup like this, however, where THEY provide the customer with a box that does everything. The customer gets a Cable/DSL Wireless Router, which gives them a router, a firewall, usually four Ethernet ports and a wireless access point and a DSL or Cable Modem all in one package.
So, while this has hopefully been somewhat informative, it PROBABLY doesn't help you with what you have to DO to make your networking hardware do what it is you want it to DO. So, what's the next step? Well, your first step should be to check the internet (possibly from a friend's house, if you're REALLY having a problem!) to see if your particular hardware vendor has their owner's manual posted online. So, for example, MY Internet Service Provider uses a brand of hardware called 2Wire Gateway for all of their in-home wireless router/DSL modems (I found this out by looking at the label on the flashing, blinking box installed in my basement). So I went looking to see if there was a configuration manual.... And here it is!