Understanding Peer-to-Peer Networks
When all PCs on the network are set up to act as equals, this is called a peer-to-peer network. Every PC shares its files and resources with the other PCs on the network. Communication among PCs is a direct link with no central network controller, such as a server.
As shown in Figure 3.1, the two PCs on this simplified network engage in direct communication, or peer-to-peer. In reality, the network can look as simple as this figure, with the PCs talking directly to each other through one cable. We will look more at the actual physical configuration of the PCs and cables later in this chapter.
Figure 3.1 A basic peer-to-peer network.
A basic peer-to-peer network can also be set up in which a piece of network equipment can facilitate this direct relationship. Remember the discussion in Chapter 2, "Home Network Building Blocks: What Makes Your Network Tick," about the network hub? The hub can, as described before, act as the central station for the direct, peer-to-peer communication between the different PCs on the network, as shown in Figure 3.2.
Figure 3.2 A basic peer-to-peer network using a hub.
At first it might not be apparent why you would want to use a hub in your network if you can connect them directly, NIC to NIC, with one piece of network cabling. We will discuss the benefits of each type of configuration in the second half of this chapter (in "Network Topologies"). For now you should know that it is easier to grow your network when you are using a hub, because you simply add a new connection from the PC to the hub.
Pluses of a Peer-to-Peer Network
The peer-to-peer network is the easiest type of network to set up. It does not require any software other than the operating system already on your PC, and it does not require the more complex configuration of a client/server network.
The following subsections cover all the advantages of a peer-to-peer network.
A peer-to-peer network is so basic that you don't need anything more than your PC's existing software, a couple of NICs, and some cable. In a wireless network, all the hardware you will need is two wireless NICs.
Peer-to-Peer Is Supported in Windows
Because most personal computers in homes today have some form of Windows, it is very easy to set up a home network. Of course, you need to have Windows 95 or a newer edition of Windows, but chances are that you do.
The cost to build a home network using peer-to-peer technology is lower than that for a client/server network because you do not need any special software or computer.
New Technologies for Home Networking Favor Peer-to-Peer
Technologies we will talk about in Part II, "Digital Plumbing: Network Wiring and Hardware Options," such as phoneline, powerline, and wireless networking, are built with the understanding that you will likely build a peer-to-peer network. This isn't to say that you can't build a client/server network with these technologies, but with these "no-new-wires" solutions, a peer-to-peer network is extremely simple.
What's Mine Is Yours
A peer-to-peer network allows each PC on the network to access resources on all the other PCs on the network. That Zip drive on Dad's PC, the laser printer downstairs on Mom's, the PC camera on Billy's PC—they're all part of the network community after you create a peer-to-peer network.
Potential Minuses of a Peer-to-Peer Network
Now that you have seen some of the advantages a peer-to-peer network can offer, you will explore some possible drawbacks peer-to-peer networks can hold. The following are the potential minuses of a peer-to-peer network.
If a PC is on a peer-to-peer network, there is the chance that another PC on the home network will access files that the owner of the PC might not want accessed. Not that this will necessarily happen or that you have something to hide from other users (or do you?), but this is something to think about. However, Windows provides the capability to block access to certain drives, so this shouldn't be a worry for anyone who properly configures her network software.
PCs Down on the Network Can Cause the Network to Go Down
In some instances, a PC might not be working, either because of problems or because it has simply been shut off. In a basic peer-to-peer network that uses direct connections from PC to PC without a hub, this might cause a problem.
In a peer-to-peer network situation in which a hub or switch is not used (such as a phoneline network), it becomes a real possibility that the network can get bogged down when more than one user is using it at the same time.
A peer-to-peer network is great for a home network with a handful of users such as three to five PCs. However, if one day you decide to go into business with Brad, your neighbor, and set up a network in your home, when you start to increase the number of users to 10 or beyond, you might want to consider moving to a client/server network.
Understanding Client/Server Networks
The other network type is a client/server network. As described earlier, client/server networks have more centralized control of the network through the network server.
As shown in Figure 3.3, the communication and services on the network are controlled through the server. The resources, such as Internet service and printer sharing, are controlled through the network server. If you were to set up passwords to get on the network, this would also be controlled through the server.
An important distinction to make here is that this does not mean that all communication needs to go through the server. In a situation in which a hub or network "central station" is used, Client A can communicate directly with Client B. However, the permission that enabled this direct connection was granted by the network "dictator," the server. Figure
3.3 is a conceptual diagram and doesn't show the use of a hub or switch that actually handles network "traffic."
Network traffic is what we call the actual communication over the network. Network gurus like to use this term to describe how "congested" (see where we're going here?) or busy the network is.
Figure 3.3 Central control through a client/server network.
Considering that a client/server network is generally more complicated and expensive than a peer-to-peer network, you're probably asking yourself why you would ever need one. Here are the circumstances in which you might want to consider using a client/server network:
You expect that your network will grow over time and might exceed 10 users.
You have a PC that has a noticeable advantage in processor speed and disk drive (storage) space.
You need to control access to your network.
You want to be able to have greater management and monitoring control over your network.
You want to set up a Web server (a special server that creates Web pages on the Internet).
These are all reasons you should consider using a client/server network over a peer-to-peer network. A client/server network, because of a more robust operating system such as Windows NT or NetWare, allows the network administrator to have better control over who accesses what and allows monitoring of network traffic and usage patterns.
Choosing Between Peer-to-Peer and Client/Server: A Suggestion for Your Sanity
As you can see, you must weigh a few basic considerations when deciding between the two options. But to give you even more value from your investment in this book, I will make a suggestion that should ease your pain considerably:
Unless you feel very strongly that you should have a client/server network based on the answers you had to the previous questions, by all means go with the much easier solution of a peer-to-peer network.
So you might be shocked that I go so far as to suggest what you should use, but don't be. That's my job (and I'm an extremely nice person).
Not convinced? Let me go over a few reasons I believe you should consider a peer-to-peer network unless you are absolutely convinced a client/server is for you:
As I've mentioned repeatedly, peer-to-peer networks are much simpler. They use your basic PC operating system and the newer operating systems, such as Windows ME and XP, have built-in wizards to help you create your home network.
Network operating systems are more complex, and you will have to learn a whole new set of commands to get your client/server network operating to your liking.
Client/server networks are more expensive.
Most home networks have only five or fewer PCs, which is well within the capabilities of a peer-to-peer network.
Most important, in a peer-to-peer network you can share files, share printers, create passwords, and do most of the things you do with a client/server network.
Don't be surprised by that last statement. A peer-to-peer network can take advantage of the resources of different PCs within the network. If one has a larger hard drive, make that one the PC where you store all your large music and video files. If you want to use dad's laser printer in the den, make sure you ask him nicely to allow sharing. For a home network, in almost all instances, you can do all the things you want to do with a peer-to-peer network.
Here's one more reason to consider a peer-to-peer network. As I've mentioned before, new products aimed specifically for home networks are coming to market, and many of these are beginning to fulfill functions that a server might have done in the past.
For example, home routers or residential gateways are available today to provide basic security against hackers and allow for Internet sharing, two functions that could have been administered by a server in the past. Media servers and network storage drives are available that allow you to store large multimedia files such as movies and music in a "media tank." Some of these products are even designed to plug right into your stereo system or TV so that they won't look like a PC sitting awkwardly in your living room.
Because I feel so strongly that a peer-to-peer network is a great fit for a home network, the rest of this book focuses mainly on explaining how to set up and use a peer-to-peer home network.