Peer-to-peer networking provides a simple, low-cost method for connecting personal computers in situations where you want to share files and other resources such as a printer. Peer-to-peer networking does not require a server, meaning the added expense of a powerful computer to act as a server and a network operating system for the server is avoided in this approach to creating small networks.
In a peer-to-peer network, the computers on the network function as peers. A peer computer basically acts as both a client and a server computer. Peer computers can access resources on the network, and they can supply resources to other peer computers (the same as a server does on a server-based network).
A peer-to-peer network is also commonly referred to as a workgroup . This is because the term workgroup connotes collaboration without central control, differentiating the peer-to-peer network from the larger-scale server-based network.
The only real requirements for building a peer-to-peer network include installing an operating system on the PCs that supports peer-to-peer networking and then physically connecting the PCs (this means outfitting the computer with a network interface card and then cabling the PCs together; in the case of Macintosh computers, you don't even need the network interface card). Before taking a look at where we are today with peer-to-peer networking and the pros and cons of peer-to-peer networking, let's take a quick look at how peer-to-peer networking has changed over the last decade .
Peer Products Come and Go
Peer-to-peer networking has been around almost as long as the PC. On the IBM PC/clone side of personal computing, the DOS operating system did not provide for peer-to-peer networking. Add-on products were required to provide the functionality for sharing files or printers over a small network. Products such as Artisoft's LANtastic and Novell's NetWare Lite (Novell no longer markets NetWare Lite or a follow-up peer-to-peer product named Personal NetWare) provided workgroup networking in the late '80s and very early '90s.
The fact that you had to actually purchase the peer-to-peer networking software obviously increased the cost of creating a small workgroup. In many offices, where only a few users shared a printer or files, sneakernet (meaning no network at all) was still the low-cost choice.
As mentioned in Chapter 2, Microsoft introduced its own peer product in 1992 in the form of Windows for Workgroups 3.11. Subsequent versions of Windows, including the latest version Windows XP, are all workgroup-ready. As Microsoft Windows became the dominant operating system for PCs, this really signaled the end of the need for additional software to add workgroup functionality to a personal computer.
Peer-to-Peer Networking Today
With Microsoft Windows dominating today's personal computing market (because of availability, usability, and acceptance as standards in the business world), peer-to-peer networking is certainly an easy-to-configure, low-cost avenue for sharing files and printers at home or a small business. Once the computers and printers in the peer-to-peer network have been physically connected, actually setting up the sharing of files and printers is a very straightforward matter (which we discuss in Chapter 6, "Configuring Peer-to-Peer Networks".)
Linux distributions also provide workgroup capabilities with other Linux clients or with Microsoft Windows clients (through the use of SAMBA, which is discussed in Chapter 6). Figure 2.1 shows the Explorer window of a Linux workstation (running Lycoris Desktop) that has been configured to be part of a Windows workgroup.
Figure 2.1. Linux workstations can also be configured to participate in a Windows workgroup.
Pros of Peer-to-Peer Networking
The pros related to peer-to-peer networking revolve around cost and ease of installation. Depending on the operating system you are running on your computers, peer-to-peer networking does not require the purchase of additional software or a computer to act as a dedicated network server. Most operating systems that support peer-to-peer networking also make it very easy for you to configure your computers so that they will communicate in a workgroup.
In a nutshell , here are the overall advantages of peer-to-peer networks:
Even though peer-to-peer networking is cheap and fairly simple to set up and configure, it is not scalable, meaning that around 10 computers at the most can live together in a peer-to-peer situation. What's more, you will still have to outfit the computers with network interface cards and connect them. If you use twisted-pair cabling, you will need a hub. If you go with coaxial cable, you will need T-connectors and terminators. Other connection strategies, such as wireless communication, will require the appropriate hardware.
Cons of Peer-to-Peer Networking
Although peer-to-peer networking appears to be the perfect networking solution in situations where you don't want to go to the trouble to install and configure a network server (or can't afford a server and the network operating system software), it does have a number of limitations. First of all, it is extremely limited as far as the number of computers you can connect together. This type of networking is really reserved for very small installations of 10 computers or less. Many experts recommend that a peer-to-peer network not include more than five peer computers; this limit is recommended because the greater the number of peers accessing information, the greater the performance hit on the peers that are providing that information. Since peer networking distributes resources across the network, having many peer shares (which each potentially require a different password) can make accessing files confusing.
Peer-to-peer networking also does not provide any centralized security on the network. Users don't have to be authenticated by a network server to actually view and potentially use the resources on the network. This is related to how resources are shared in a workgroup.
Each resource that is shared (such as a drive, folder, or printer) can potentially require a different password for access. If a lot of resources are shared across the network, you will have to remember the password for each resource. This type of security is referred to as share-level security ; each drive, folder, or printer that is shared is referred to as a share .
A summary list of peer-to-peer network shortcomings follows :
Peer-to-peer networking definitely needs to operate in an environment of cooperation. If your users can't play well together, you will have problems because the users themselves control the various resources. Peer-to-peer networking is, however, a good way to share resources on home networks and small, single-office business networks. If you simply want to share a printer between a few computers or build a gaming network, peer-to-peer is the way to go.