Simply Digital

Episode 9: Basic Networking

The topic of computer networking can be somewhat intimidating, but once you understand that basic building blocks of what makes up a network, it’s really quite simple. Armed with the right information, you can troubleshoot a network problem, share your broadband Internet connection, or even create a complete network of your own.

In episode 9, Michael Ashby and Analog Dave talk about the basics of a local area network (LAN). There are a lot of terms and acronyms, but each term is explained in detail and the show notes have plenty of further information.

Show Notes

• We updated our recording equipment, so all future episodes should sound much better.
• As a reminder, we don’t tell Analog Dave what the show topic is going to be so that he can be fresh and act as our “watch dog” for the topic to make sure that we cover all the bases.

1. What Is A Network?
   • Two or more computing devices connected together. More at Wikipedia.
   • These can be computers, pdas, Gameboys
   • The Internet is also a network
   • There have been a wide variety of network types, or protocols, but the most popular network is based on TCP/IP (which stands for Transmission Control Protocol / Internet Protocol).
   • This is the same protocol that is used for the Internet
   • Because of WiFi, or wireless networking, the idea of having a network in the home is becoming more and more popular.
2. What Is A LAN?
   • LAN stands for Local Area Network
   • If you’re setting up a home network, you’re setting up a LAN.
   • If your office has a network, then it too is a LAN, although you might call it a corporate LAN, or corporate network.
   • All a LAN is, is a group of networked computers. It’s a fancier and easier to say term.
3. The Building Blocks Of A LAN
   • What Is Ethernet?
     • It is a standard network cable that is used on most networks. It’s just a cable.
     • You use an Ethernet cable to connect your computer to other LAN devices, such as a hub, or switch.
   • What Is A Hub?
     • A hub is a device that connects multiple network devices together.
     • Depending on how many “ports” you have on the hub, you can connect that many computers. 10 port hub can connect 10 computers together, etc.
   • What Is A Switch?
     • A switch is similar to a hub, except that it’s faster and more secure.
     • A hub is not discreet, but a switch is.
     • If given the choice, we recommend that you purchase a switch over a hub.
   • What Is A Router?
     • A router is a device that connects two networks and routes the data between them.
     • Most often in a home network, a router is used to connect your LAN to the Internet, thereby sharing your Internet connection with all of the computers in your home.
     • Regardless of the type of high speed Internet connection is, a router would connect the same way.
     • Technically, you are sharing your Internet connection with your other computers, which means that one user could use up most of the bandwidth. In other words, the other users would have a slower connection; however; this isn’t something you usually have to worry about. The “bandwidth hog” would have to be doing something very intensive online for the other users to notice a slowdown.
     • For more on routers and firewalls, we recommend that you listen to Episode 2: Firewalls.
   • What Is A Firewall?
     • This is a hardware or software device that protects a LAN from an outside network (typically the Internet)
     • For our purposes, all consumer routers will include a firewall.
     • With today’s consumer routers, they often include switches, wifi, and many other services as well
     • Again, for more on routers and firewalls, we recommend that you listen to Episode 2: Firewalls.
   • What Is A IP Address?
     • Every computer or device that is on a TCP/IP network (LAN or Internet) is given a unique number. This number is called an IP Address, or Internet Protocol Address.
     • The purpose of an IP Address is to ensure that each computer/device can be uniquely identified on the network.
     • Without this numbering system, information could get lost because the network wouldn’t know which computer to send the information to.
     • A LAN IP address can often look like 192.168.1.10
   • What Is A Network Card (NIC)?
     • A Network Card (NIC) is really nothing more than an adapter that connects your computer to a network.
     • A NIC can be wired or wireless.
     • If wired, an Ethernet cable is needed to physically connect your computer/device to the rest of the network.
     • If a wireless NIC is used, then a wireless access point is required on the network that you wish to connect to.
     • Most modern computers have network cards built-in and most laptops also include a wireless nic as well.
4. How Do I Share My Broadband Internet Connection?
   • You need to use a router.
   • The router sits between your computer and your broadband modem.
   • Your Internet Service Provider (ISP) typically supplies you with an IP address for your computer. When you install a router, the router will be assigned this public IP address
   • A pubic IP address is an IP address that can be “seen” on the Internet.
   • Your router has the public IP address and then it assigns all the computers on your local LAN with private IP addresses. This is what secures your network.
   • Your computer has a private IP, meaning that no one on the Internet can see it, and the router acts as a conduit to “go out and get what you need” off of the Internet.
5. What Is The Difference Between A Static And Dynamic IP Address
   • When IP addresses are assigned to a computer, they can be a dynamic IP, or a static IP.
   • A static IP address simply means that it never changes. It is a permanent assignment of a unique IP to a particular computer/device.
   • A dynamic IP is an IP address that is assigned out of a pool of numbers and can change over time.
   • Dynamic IP addresses are the most common and easiest to use.
   • Static IP addresses are good for when you want to connect to a specific device and know that it’ll always be at that address.
     • Perhaps you want to network a printer. In this case you will want the printer to have a static IP so that your computer will always be able to find it and print.
     • Or perhaps you’d like to be able to reach your LAN via the network when you’re away from your home/office. If your ISP assigns your router a dynamic IP address, it makes it harder to reach your network. There are ways around this problem, such as using Dynamic DNS, but a static IP would be an easier solution.
6. Is There A Way To Access My Home LAN When I’m Not At Home?
   • This is a somewhat advanced topic, but if you’re looking for an easy way to access your home PC when you’re away from home, we highly recommend Avvenu. It’s a free service and easy to use.
   • You install a small application on your computer (Windows only as of this recording) that connects you to Avvenu.
   • When you’re away from home, you log into the Avvenu web site with your web browser and you can access the data on your home PC.
   • You can install Avvenu on as many computers as you want and access them all via one web page.
   • It’s important to note that Avvenu only allows you access to the data on your computer, you’re not taking control of your computer remotely. So you’ll be able to grab a Word document, or .mp3, but you’re not opening Microsoft Word on your home computer, or launching your e-mail client.
7. Important Router Tips
   • If you’re installing a router on your network, it’s VERY important that you change the default password for the router.
     • Install your router between your computer and your cable modem.
     • Look in the “Quick Start Guide” that came with your router and see what the default IP address is for your router. It’s usually something like 192.168.1.1
     • In your web browser (Internet Explorer, Firefox, Safari, etc), type in the IP address for your router. This will load the administrator web page for your router.
     • Log in using the default settings that are listed in the “Quick Start Guide”
     • Browse to the area where you can change the password. The default is usually “password”, so change it to something that you can remember.
     • If you want to make sure that your password is as secure as possible, we recommend that you use the “Perfect Passwords” Generator on the GRC.com web site.
   • We recommend that you turn off “Remote Management” on your router.
     • It could be called something other than Remote Management, so check your manual, but this is typically a check box in the control panel of your router.
     • To access the control panel, you just type in the IP address of the router into your web browser (see above for details).
     • Remote Management allows you to access the router control panel from outside your network. This means that you could access it via the Internet
     • It’s not a good idea because if your password is cracked, then anyone could take complete control of your router.
   • We recommend you turn off UPnP (Universal Plug and Play)
     • Unless you know that you specifically need this feature, go ahead and turn it off on the router.
     • You turn off this feature in the router’s control panel. For details on how to access it, see above.
   • Secure Your Wi-Fi
     • This is a topic for a future podcast, but if you use a wireless (aka Wi-Fi) router, be sure to encrypt your wireless signal. This will secure your wireless signal.
     • If you don’t secure your signal, anyone in range with a wireless NIC could access your network.
     • We recommend that you use WPA Encryption.
     • This create an additional password just for your wireless users.
     • You set up your wireless encryption on the router, through the control panel. This is where you choose the type of encryption and what the password is.
     • Then you enter the password each of the wireless computers/devices on your network.
   • Bookmark the address to your router’s control panel, so that you can easily find it in the future.
   • Good rule of thumb: If you’re trying to use an online service, such as video chat, and it’s not working as you expect, chances are good that you have to open a port on your router.
8. Travel Tips
   • Open and free Wi-Fi, such as what you might find at a hotel or coffee shop, is not secure.
   • Connections in a hotel, including wired networks, are rarely secure.
   • Why is this important? Well, if you travel with a laptop and are looking to connect to the Internet, most of what you’re doing is not secure and could be seen by other users.
   • To secure your connection, you need a Virtual Private Network (VPN)
   • We recommend that you use a service like HotSpotVPN to secure all of your traffic - wired or wireless.
   • Also, check with your company, they may have a VPN connection available to it’s employees for free.

For More Information:

• Security Now #27: How LANs Work, Pt. 1
• Security Now #3: How the Internet Works, Part 1

The Bottom Line
Once you know the basic building blocks of a network, it is fairly easy to create one for yourself. In fact it works much like the familiar song Dem Bones song. The NIC connects to a hub or switch, the switch connects to the router and the router connects to the Internet, etc.

If you have more than one computer at home, that’s a great opportunity to create a small home network. Start with a router and work out from there. Today’s routers come with a lot of built-in network components (switch, firewall, wifi access point), so it’s a great place to start. Once you’re comfortable with that piece, you can branch out from there.

Entry Filed under: Podcasts

Digg this Post to del.icio.us Linking blogs