Welcome to Part One of HardwareCentral’s Ultimate Guide to Networking! We’ll start the guide with an introduction to networking, a run-through of networking terms and lingo, and descriptions of networking hardware.
What is a Network?
A network is simply a group of two or more Personal Computers linked together.
What Types of Networks Exist?
Many types of networks exist, but the most common types of networks are Local-Area Networks (LANs), and Wide-Area Networks (WANs). In a LAN, computers are connected together within a “local” area (for example, an office or home). In a WAN, computers are farther apart and are connected via telephone/communication lines, radio waves, or other means of connection.
How are Networks Categorized?
Networks are usually classified using three properties: Topology, Protocol, and Architecture. Topology specifies the geometric arrangement of the network. Common topologies are a bus, ring, and star.
You can check out a figure showing the three common types of network topologies below.
Protocol specifies a common set of rules and signals the computers on the network use to communicate. Most networks use Ethernet, but some networks may use IBM’s Token Ring protocol. We recommend Ethernet for both home and office networking. Architecture refers to one of the two major types of network architecture: Peer-to-peer or client/server. In a Peer-to-Peer networking configuration, there is no server, and computers simply connect with eachother in a workgroup to share files, printers, and Internet access. This is most commonly found in home configurations, and is only practical for workgroups of a dozen or less computers. In a client/server network, there is usually an NT Domain Controller, which all of the computers log on to. This server can provide various services, including centrally routed Internet Access, mail (including e-mail), file sharing, and printer access, as well as ensuring security across the network. This is most commonly found in corporate configurations, where network security is essential.
Now that you have a basic understanding of networks, we’ll learn about the type of network most people will want to setup, a Local-Area Network.
Local-Area Networks
Originally, only medium to large-sized businesses could afford the cost of networking hardware. In the last decade, prices have rapidly dropped as new technology has developed, and it is now possible to grab a basic 4-PC 10Base-T home networking kit for under $150. The affordable price and added convienence of having a LAN has made it commonplace to see networks in many homes and offices. Each PC in a LAN is able to access shared files and devices anywhere on the LAN. This makes the sharing of expensive devices, such as laser printers or large removable storage drives, a cost-effective alternative to purchasing a device for every user.
If you decide to use Ethernet for your LAN (which we recommend you do), you can choose from 10Base-T (10 million bits per second, or 10 Mbps) or 100Base-T (100 million bits per second, or 100 Mbps), which is usually refered to as Fast Ethernet. 10Base-T is used mostly for home and small office networks, because it offers both affordability (around $20-30 for a network card, and $80 for an 8-port hub) and decent performance. For large businesses, a 100Base-T solution may be required if there are a large number of PCs connected to the network, or if large amounts of data is frequently transferred.
There are three different types of cabling for Ethernet networks. Unshielded Twisted Pair (UTP) is the most popular type of cabling, and the one we recommend because of its wide availibility and low price. The other two types are coaxial and Shielded Twisted Pair (STP). STP cable provides more shielding against outside Electromagnetic Interference (EMI) than UTP, but is more expensive. We’ve never had any problems with EMI, so we suggest the cheaper UTP. Coaxial uses much thicker and more expensive cable, and must be run in a ring configuration, from PC to PC, unlike Twisted Pair, which is run directly from each computer to a port on the hub, making wiring more convienent in most cases.
Ethernet networks require a Hub, a hardware device that all PCs on a network are connected to by cabling. The hub manages receiving and transmitting data from networked devices. Hubs come in many different port configurations, but you will probably need a 4, 8, or 12 port hub, depending on the number of PCs you want to connect together. Each port supports a single 10Base-T connection from a PC or peripheral. If you’re using Coaxial cable, you need to find a hub with one Coaxial port and minimal Twisted Pair ports. There are both Manageable Hubs, which allow advanced configuration of Hub properties via a software package, and Standard Hubs, which are cheaper, and usually used for home or small office networks. We recommend purchasing a standard hub, since the extra features included in Manageable Hubs are not useful for a home or small office network. Since you will probably purchase a standard hub, we’ll discuss the three types of standard hubs next.
Standard Hubs
When thinking about what type of Standard Hub you want to purchase, you need to think about what you will be doing with your network in the near future. Will you be adding many more devices to your network? If so, you need to make sure your hub can handle network expansion.
Standalone Hubs
Standalone hubs are single products with a number of ports. Standalone hubs usually include some method of linking them to other standalone hubs for network expansion. Standalone hubs are usually the least expensive type of hub, and are best suited for small, independent workgroups, departments, or offices, typically with fewer than 12 users per LAN.
Stackable Hubs
Stackable hubs work just like standalone hubs, except that several of them can be “stacked” (connected) together, usually by short lengths of cable. When they are connected together, they act like a modular hub, because they can be managed as a single unit. These hubs are ideal if you want to start with a minimal investment, but realize that your LAN will grow.
Modular Hubs
Modular hubs are popular in networks because they are easily expanded and always have a management option. A modular hub is purchased as a chassis, or card cage, with multiple card slots, each of which accepts a communications card, or module. Each module acts like a standalone hub, and usually has 12 twisted pair ports. Modules supporting different types of network cabling, like coaxial or token ring, can also be purchased.
If you are building a home or small office network, you will probably want to purchase a standalone or stackable hub. For a medium to large sized company, a Modular hub will probably fit your needs more efficiently. Next, we’ll take a look at other types of network hardware, like routers, bridges, and switches.
Bridges, Routers, and Switches
Bridges and routers are devices used for linking different LANs or LAN segments together. There are many companies that have LANs at various offices across the world. Routers were originally developed to allow connection of remote LANs across a wide area network (WAN). Bridges can also be used for this purpose. By setting up routers or bridges on two different lans LANs and connecting them together, a user on one LAN can access resources on the other LAN as if they were on the local LAN.
Sample Network Layout With a LAN Switch, Courtesy of Bay NetworksThere are maximums on distances between workstations and hubs, hubs and hubs, and stations connected to a single LAN. You can exceed these maximums by linking two LAN segments (groups of users/devices) together using a Bridge or Router.
Bridges
Bridges are simpler and less expensive then routers. Bridges make a simple do/don’t decision on which packets to send across two segments they connect. Filtering is done based on the destination address of the packet. If a packet’s destination is a station on the same segment where it originated, it is not forwarded. If it is destined for a station on another LAN, it is connected to a different bridge port and forwarded to that port.
Routers
Routers are more complex and more expensive than bridges. They use information within each packet to route it from one LAN to another, and communicate with each other and share information that allows them to determine the best route through a complex network of many LANs.
Switches
Switches are another type of device used to link several LANs and route packets between them. A switch has multiple ports, each of which can support either a single station or an entire Ethernet or Token Ring LAN. With a different LAN connected to each of the ports, it can switch packets between LANs as needed.
Conclusion
This first part of the Ultimate Guide to Networking should have given you an informative overview of networks and networking hardware. In the next two parts, which will be posted next Monday (the 18th), and the Monday after that (the 25th), we’ll cover setting up peer-to-peer and client/server networks using both MacOS and Windows 95/98/NT PCs.