The best thing about wireless LANs is that they are extremely easy to build compared to their wired counterparts. However, wireless LANs require far better understanding of the technologies involved and careful planning to provide a flawless, high−performance, and secure operation.
An unplanned wireless LAN could result in severe problems due to bad performance and security issues. In order to plan a secure wireless LAN, you must have a good understanding of the following:
- Basic networking concepts.
Except for the physical transmission characteristics of wireless LANs, wireless LANs are almost identical to wired LANs. All the basic networking concepts that apply to one also apply to the other. Therefore, it is important to understand basic networking concepts.
- Wireless LAN technologies, basic equipment, and standards.
Wireless LANs are based on relatively new technologies when compared to wired LANs, which have been around for a while and are well understood.
The technologies involved in wireless LANs are constantly evolving, resulting in newer equipment and standards. When selecting wireless LAN equipment, it is important that all available technologies are evaluated to ensure the best possible performing LAN that fits your needs and budget.
- Security issues with wireless LANs.
When deploying a secure wireless LAN, security primitives of the technologies must be well understood.
- Whether wireless LANs are right for you.
You might be able to answer this question by reading previous tutorials, or you may be able to better answer this question when you have finished planning your wireless LAN.
Documenting the planning stages is one of the most important tasks when planning a LAN deployment. Documenting the planning steps ensures that you follow a guideline.
Unfortunately, this step is often skipped when networks are planned, resulting in the realization, perhaps too late, that key factors or important tasks and objectives have been overlooked.
We suggest that you take notes and document your planning process as you follow each step in this tutorial. Let's start planning for a wireless LAN. There are seven basic steps involved in planning a secure wireless LAN.
Step 1: Understanding Your Wireless LAN Needs
The primary and foremost step when planning a wireless LAN is to understand your own wireless LAN needs. This ensures that you have accounted for most LAN services that you desire to use in a wireless LAN.
It also helps you select the type of wireless LAN that satisfies your needs. In Step 1, we help you identify the services you want from a wireless LAN, and help you plan for the type of wireless LAN that might best fit your needs.
Identifying the computer programs and applications that you will be running on the computers accessing the wireless LAN is of critical importance as it helps you decide whether wireless LANs satisfy your primary needs or not.
Understanding your LAN requirements is of even more importance where a wireless LAN is aimed to replace an existing wired LAN. In this scenario, if the desired services are not considered in the planning phase, the resulting wireless LAN could lack the basic features that were available in the wired LAN.
We suggest that you inventory and identify all the software applications that need to access data and resources on the network. Special attention should be given to applications that use streaming audio and video as well as client applications accessing large amounts of data.
- File and Application Servers
Most LANs are used for sharing files among users. These files reside on the large−capacity hard disks on computers, which can be standalone file servers or workstations, and are connected to the network.
In addition to file−sharing services, network−based application programs must be considered. These application programs could be email servers, accounting software, or a Web server.
Considering file and application servers is important because if wireless LAN hardware or software will not properly support the computers that provide these services, the entire wireless LAN could easily become useless.
- Print Servers
The ability to share printers is another big use of LANs. If a printing feature is to be supported on the wireless LAN, ensure that it is accounted for when planning for wireless LANs. When setting up the wireless LAN, you will have to decide how to connect printers to the wireless LAN
- The Internet Access
Internet access has become one of the prime uses of LANs. LANs normally share a high−speed connection among users. You should consider how you want to share the Internet connection among users of a wireless LAN.
Depending on the deployment scenario, desired connection bandwidth must be considered in order to provide a high−bandwidth solution to the users of wireless LANs.
- Miscellaneous Network Appliances
All other devices that are to be attached to a network must be considered when defining the services you need from a wireless LAN. Such devices could include a modem pool, tape backup, or site−security systems.
- Select Suitable Type of Wireless LAN
Selecting the type of wireless LAN you need depends on a number of factors, including: the number of intended wireless LAN connections, the deployment scenario (for example, home use, SoHo, enterprise, or WISP), security, and the external connectivity desired.
- Peer−to−Peer or Ad−Hoc Wireless LAN
Peer−to−peer wireless LANs consist of two or more computers, generally without any type of server (for example, file server or mail server). Instead the computers communicate directly with each other.
Such wireless LANs have limited use and are only deployed in small LAN settings like home or SoHo environments.
- Standalone Wireless LAN
Standalone wireless LANs consist of one or more computers and may include a file server and other shared network resources. These LANs are considered relatively secure as they are normally not connected to the Internet or any external network.
Such networks are generally used in SoHo, retail businesses, and manufacturing environments.
- Wireless LAN as a Replacement for a Wired LAN
Many organizations are replacing their wired LANs with wireless LANs. Creating a wireless LAN in place of a wired LAN provides mobility to the users and makes future LAN upgrades a little easier.
For example, to upgrade a wired LAN, you often have to replace the physical wiring, whereas wireless LANs do not have this requirement. To upgrade wireless LAN technology, only wireless LAN equipment and software need to be upgraded and the new LAN becomes operational.
Total replacement of a wired LAN with a wireless LAN is a big task and should be carried out with great caution. Conduct a small pilot first before rolling out the full−blown wireless LAN.
- Wireless LAN as an Extension to a Wired LAN
A good idea when deploying a wireless LAN is to first deploy it as an extension to an existing wired LAN. This means that you leave the wired LAN intact and add a wireless LAN as a supplementary network to the original LAN.
This allows a smooth division of the existing LAN, in which the computer systems that are required to be on the wired LAN stay on the wired LAN and those needing wireless connectivity are upgraded with the wireless LAN equipment.
It is, however, important to remember that the wireless LAN technology available today operates at slower speeds than its counterparts, the wired LANs.
Therefore, it is often a good idea to deploy a wireless LAN as an extension to a wired LAN, where all computers and devices requiring high network bandwidth are connected to the wired LAN and the workstations or peripherals that require lower bandwidth are connected using the wireless equipment.
Once you understand your needs for wireless LANs, you are ready to plan the scope of rollout and set up the requirements and expectations for the LAN you are willing to deploy.
Step 2: Planning the Scope of Rollout
As the second step, you should define the rollout scope of the wireless LAN you are planning to deploy. You should decide whether you want to deploy the entire wireless LAN at once or begin by first doing a pilot and then progressively roll out the actual wireless LAN.
The incremental rollouts help you better understand your needs and allow you to choose the right technologies. We suggest that you first plan a pilot then roll out a full−blown wireless LAN.
If you are replacing a wired LAN with a wireless LAN, you might want to try first using wireless LAN in conjunction with the wired LAN and then replace the actual wired LAN to avoid any negative surprises.
