Home Networking: Routers

Add Your Comments

Routers

Several companies are now producing hardware specifically meant for connecting a LAN to a WAN – a home network to the Internet. Such a device usually looks like a hub and can be had for $140-$200 US (mailorder) from manufacturers such as Linksys, Netgear, Lucent Technologies, Adtran, Dlink, and SMC. More pricey models are available from a lot of network companies, and even Cisco is getting in on the action.

These devices usually include a bunch of cool things that will help make life easier and I’ll discuss them right now…

Built-in switches – A lot of these devices sport a multi-port switch, usually four ports. (Linksys offers both a one-port and four-port model) These switches are usually 10/100, meaning that they work nicely whether your network uses Ethernet (10baseT) or Fast Ethernet (100baseTX). Switches are more intelligent than hubs, routing packets to and from specific ports instead of echoing all data to all ports at once, which makes a switch a good bit faster since packet collisions are much less frequent.

DHCP Server – DHCP stands for Dynamic Host Configuration Protocol. What makes DHCP nice is that it simplifies the networking setup on each computer on the network. All you do is set up the DHCP server on the router, and tell each computer to gets its configuration information from the router. The router’s DHCP server will assign IP addresses and set up each computer’s networking correctly by itself. However, if you need to have specific IP addresses assigned to specific machines, most routers allows you to turn off the DHCP server and run a fixed-IP network. I’ll discuss both approaches later on.

NAT – NAT stands for Native Address Translation. This is a packet-routing technology that can allow multiple computers to share a single connection to the Internet. It works very nicely and allows the easy inclusion of the next feature – a firewall. It also means that you can have any number of computers share a single IP address, which is great for cable modem and DSL users. Better still, NAT allows multiple-port tasks such as Internet games, where other Internet sharing methods such as traditional proxy servers have a hard time with applications that use multiple ports.

Hardware firewall – In this era of always-on broadband connections to the Internet, security is not just a good idea, it’s a requirement. A hardware firewall allows tight control over what data enters and leaves your network, as well as who gets to enter and exit your network.

While there’s no such thing as being totally hack-proof, a hardware-based firewall is a major step in the right direction. Along with a software firewall on each computer behind the hardware firewall, you’re about as hack-proof as a home network can get.

Some home-networking routers include other features, such as COM ports for external modems (as a fallback plan in case the broadband connection dies), print servers (to permit sharing one printer across the network), firmware upgrade capability (so the router’s firmware can be easily upgraded), remote administration, access control, VPN/PPoE/PPTP support, and so on.

The upsides of using a router are:

No need to use a computer as the Internet connection server – Traditionally, one computer will serve as the “gateway.” (No, I’m not referring to the cow-motif computer company… in this context a “gateway” is a device, in this case a computer, that acts as the connection point from network to Internet.) This one computer often has to have two NICs if the Internet connection is broadband – one to connect to the network, the other to the cable modem or DSL router. Or, if using dialup, the modem will be the connection method and the NIC connects that computer to the network. Using a router eliminates the need to do this and correspondingly eliminates a number of problems associated with using a computer as a gateway. (Just reboot that computer when someone is using another computer on the network to access the Internet and you’ll see what I mean.)

A number of computers can share one IP address transparently – Most cable modem providers don’t like the notion of sharing Internet connections across multiple computers since the bandwidth – the total speed that data can be sent or received across the Internet connection – is shared among many users. If you’re not sharing the Internet connection, somehow you’ll need an Internet IP address for each computer and cable modem providers charge extra for each additional IP. Using a router eliminates the extra monthly costs for additional IP addresses by permitting up to x number of computers (often 253) to share the one connection.

Operating-system independent operation – A router generally doesn’t care what operating systems are at work on the network. Using a computer as the gateway often involves having to use a software package to make that computer act as a gateway and these are often OS-specific. If you’re using a mixture of Linux and Windows systems on your network, a router will make your life a LOT easier.

There are downsides to everything. The cons of using a router are:

Cost – SMC’s Barricade router costs $140-$160, Linksys’ EtherFast router with a 4-port switch costs $160-$180, Netgear’s RT314 router costs $150-170. (All prices are estimates US mailorder prices, not including shipping, as listed on PriceWatch as of 12 October 2000.) Routers are not cheap.

Complexity – Setting up a router can be a bit more involved than setting up a hub, since you have to set up the router’s NAT and any features it has that you intend to use. The networking on each computer can be simple (if you’re using the router’s DHCP server) or a bit more complex (if you’re not using the DHCP server) and often if the network is already up and running needs no changes at all. (In that case, one would configure the router to work with the existing network instead of setting the network up to connect to the router.)

However, setting up a router is often EASIER than setting up an Internet connection sharing without one!

In the previous sections of this article, Daniel discussed his experiences as a networking newcomer with the Netgear EN104 4-port hub and using a computer as a proxy server. In this section I’ll discuss using a router to make life a bit easier.

The router I’ll be working with is SMC’s Barricade SMC7004BR router. So my screenshots and instructions will be for that product.

However, there are a lot of similarities among home-networking routers, so you should be able to figure out your equipment if you don’t have a Barricade. Visit http://www.smc.com/smc/common/7004.html for more info on the Barricade.

I also use a cable modem and @Home’s service to connect, so my notes will be with that in mind. Again, you’ll need to adjust for your specific circumstances.

The Barricade has a 4-port 10/100 switch, NAT for Internet connection sharing, hardware firewall, DHCP server for easier setup, a print server, a COM port for a modem, and supports practically any protocol that works over the Internet. And at $139 (mail-order) it’s cheap, which I especially like. 😉

I purchased mine via mail-order. When it arrived, I unpacked it to find the router itself (a little black box), a power cube and power cable (the cube is one of those intelligent deals that work on US or European house lines), an intallation/manual CD, two 6-foot network cables, and a single page quick installation guide.

The installation guide doesn’t tell you much and the manual is on the CD as both an Adobe Acrobat PDF file and a Microsoft Word document. (The viewers for these are also on the CD.) That left me glad I know how to work with networking hardware already, so I knew what to do for the most part before I opened the box.

Next: Router Installation

Email Odd One


Here’s what I did…

I plugged the power cable into the power cube, and plugged its lead into the power jack on the router after making sure it was OFF. (You don’t want to power up the router while hooking it up the first time.)

I then plugged the cable modem into the WAN jack on the back and plugged each computer into the switch.

Finally, I decided not to try the print server yet so I left the printer connection on the router unused. Since I don’t use a modem for my Internet connection the router’s COM port remained unused as well.

I flipped the switch and the router started itself up, performing a few self-tests. The router then started to flash it’s “I’m on, I’m happy” light and I knew it was time to set up the router.

I wanted to use the DHCP server and all my computers were already set up for that, so all I needed to do was reboot each computer.

On starting, Windows would ask the route for network configuration data and would set itself up.

I logged onto the network and tried to access a web page. Nothing! Oops, need to set up the router. So, I checked the quick-installation guide on that single piece of paper and got the router’s website URL. Yes, the router has its own mini-website and from there you can configure its settings! The default for the SMC Barricade is http://192.168.123.254/ although you can change it. So I plugged that URL into the web browser and poof, got the configuration screen.

Barricade Config

(NOTE: I blurred out some of the specifics on my setup, such as IP address, DNS nameservers, etc. Your specifics will vary.)

In order to prevent bad things from happening, routers usually make you log in to make changes to their configurations, and the Barricade is no different.

I used the default login (which should be changed immediately!) and the router presented me with a number of options. The first thing I did was click the Toolbox menu option and change the password. (No, I won’t tell you what I changed it to. :-p)

With that done, it was time to set up the DHCP server. So I clicked the Primary Setup menu item.

Barricade Primary

The router defaults to thinking it will be using the IP range 192.168.123.x. The router itself always uses x.x.x.254, which in this case meant that the router was 192.168.123.254.

I prefer using 192.168.0.x just for simplicity’s sake, so I changed the LAN IP Address to 192.168.0.254, so that the router would use 192.168.0.x for the DHCP server when I set that up later on.

This meant that the router was now accessible by http://192.168.0.254/

Since I use @Home’s cable modem service, I had to set up the DHCP server to connect to their DHCP server so the router would itself be asking for configuration information. So I set the router to get its IP address dynamically (read: ask @Home’s DHCP server to assign its IP address) and entered the hostname @Home issued me (often similar to CX123456-A) in the Host Name box.

Since the Barricade has the option to automatically renew DHCP leases (which basically means that the router will re-acquire an IP address when the DHCP server revokes it after a certain length of time)

I added the check in the appropriate box. I then clicked the Save button to save the changes.

Now it’s time to set up the router’s DHCP server so my network computers are all set up automatically. I clicked the DHCP Server menu item.

Barricade DHCP

The DHCP server is enabled by default on the Barricade, and it was assigning IPs 100-199 to my network computers. So the first computer to log in that day would be 192.168.0.100, the next would be 192.168.0.101, and so on.

The Barricade allows up to 253 computers to share one connection, so I changed the IP Pool Starting Address to 1 and the IP Pool Ending Address to 253 (the router itself is 254).

So now my first connected computer would be 192.168.0.1. (Side note: You cannot use zero as a starting IP value, and you cannot use 254 as that’s the one the router will use.)

Since @Home uses a specific domain name, often city.state.home.com, I plugged that into the Domain Name box. I then clicked Save to save the changes.

All done, time to reboot the router so the changes would take effect. I clicked the Toolbox menu item again and then clicked the Reboot button to make the magic happen.

I then tried to reach a website and was greeted by a nice sight – the Overclockers.com website loading as if the cable modem were plugged directly into my computer! Success!

That was basically all I needed to do to get the Barricade set up. Took all of five minutes from opening the box to accessing the first webpage through the router.

Fixed IP Addresses

I do a LOT of tasks that require having a known IP address on each computer. DHCP assigns IPs as they are needed, so the IP address could change each time the computer connects to the network.

This would not be good for me, so I knew I had to set up my network to use fixed IP addresses for each computer and turn the Barricade’s DHCP server off. This is a bit trickier since it requires reconfiguring the computers themselves. However, it’s a fairly straightforward process…

What you’ll need to do first if you’re going to set up a fixed-IP network is decide which computer will use what IP address, and give each computer its own unique name. (“Unique” as in not duplicated on your network by any two computers.) For example, on my two-computer network my computers are named Hunk-O-Junk (“hunkojunk”) and Piece-O-Crap (“pieceocrap”). I want Hunk-O-Junk on 192.168.0.1 and Piece-O-Crap on 192.168.0.2. So, I started by setting up Hunk-O-Junk as follows:

First things first – Turn off the DHCP server on the router. I accessed the router’s configuration website, logged in, and disabled the DHCP server. Then I rebooted the router and proceeded to the set-up-the-computers phase.

I right-clicked Network Neighborhood and then clicked Properties to open the Network applet. (This can also be done from My Computer > Control Panel > Network.)

Since I’m not using a domain controller, I clicked the Identification tab and entered a name for the workgroup I’d be using into the Workgroup box. All the computers on the network must have the same workgroup name or they won’t “see” each other in Network Neighborhood. The Computer Name box received the computer’s name, as all uppercase and with no punctuation or spaces. I entered some text to describe the computer into the Computer Description box. While all computers have to have matching workgroups, their names must not match, so note what you’re doing so you don’t duplicate a name.

I then clicked the Configuration tab and scrolled down the list to find the TCP/IP entry that pointed to my Netgear NIC. A quick double-click of that entry and I got the TCP/IP properties for my NIC. This window always starts with the IP Address tab active, so I made the IP address change to produce this:

Hunkojunk

Note the subnet mask, which indicates that Hunk-O-Junk will only “see” computers with IP addresses of 192.168.0.x.

I clicked the WINS Configuration tab and disabled WINS Resolution as it isn’t needed.

However, I DO need to define the gateway, so I clicked the Gateway tab and added 192.168.0.254, the router’s IP address, to the list of installed gateways.

Now the computer would know to route all Internet traffic through whatever was on 192.168.0.254, which in this case was the Barricade router.

Next, I clicked on the DNS Configuration tab. Things in here are important when you’re not using a DHCP server to set the networking up automatically, as wrong entries in here mean your Internet connection will not work!

I enabled DNS by clicking that option. I typed the computer’s name (which must have no spaces or punctuation and be all lowercase, so it looks like ”hunkojunk” without the quotes) into the Host box.

I then added the DNS server IP addresses supplied by @Home into the DNS Server Search Order list, one at a time. I left the Domain box and Domain Suffix Search Order list empty.

This way Hunk-O-Junk would know where to look to resolve domain names to IP addresses (such as resolving Overclockers.com to 208.249.124.215.)

Once that was done I OKed my way back out and rebooted when asked.

I did the same thing to Piece-O-Crap, with the exception of using the other IP address and “pieceocrap” for the host name. Again, the same workgroup was used and that computer was rebooted. When all computers were back on the network, I opened up Network Neighborhood, and lo and behold…

Nethood

We have a winner! Both computers were accessible to each other and had access to the Internet!

I opened a MS-DOS prompt and typed ping 192.168.0.2 from Hunk-O-Junk and got four ping replies, each less than ONE millisecond later. Gotta love switches!

Nethood

All is well. I have full network capability, full Internet access for all computers on my network, and hardware firewall protection for my network.

Not bad for five minutes’ work and about $200 in hardware (the Barricade router, two Netgear FA310TX NICs, and a 50-foot Ethernet cable to tie the two computes to each other.)

As I add computers, all I need to do is set them up the same way with a unique IP address and name and plug them into the router.

Life is good. J

Email Odd One


Leave a Reply

Your email address will not be published. Required fields are marked *