What Is A WLAN: What Is It & Why Do You Need It?

A wireless local area network (WLAN) is a wireless distribution method for two or more devices. Also sometimes called a local area wireless network (LAWN), WLANs use high-frequency radio waves and often include an access point to the Internet.

A Wireless LAN allows users to move around the coverage area, often a home or small office while maintaining a network connection.

WLANs and Access Points

Every component that connects to a Wireless LAN is considered a station and falls into one of two categories: access points (APs) and clients.

Access points or APs transmit and receive radio frequency signals with devices able to receive transmitted signals; they normally function as routers.
Clients, on the other hand, may include a variety of devices, such as desktop computers, workstations, laptop computers, IP phones, and other cell phones and smartphone devices.

All stations able to communicate with each other are called basic service sets (BSSs), of which there are two types: independent and infrastructure. Independent BSSs (IBSS) exist when two clients communicate without using APs, but cannot connect to any other BSS. Such WLANs are called peer-to-peer or ad-hoc WLANs.

The second BSS is called an infrastructure BSS. It may communicate with other stations but only in other BSSs and it must use APs.

Emergence of WLANs

In the early 1990s, Wireless LANs were very expensive and were only used when wired connections were strategically impossible. However, by the late 1990s, most WLAN solutions and proprietary protocols were replaced by IEEE 802.11 standards in various versions. Wireless LAN prices also began to decrease significantly.

And as technology progressed, WLANs became easier and easier to set up and administrate.

This led to the emergence of the ISP Wireless LAN, where many small local home networks are coordinated by the Internet Service Provider, and not engineered by the end-user on-site. In these types of ISP WLAN setups, the ISP’s modem is the access point and also the router. All that the consumer has to do is plug in the WiFi router, use provided security passwords, and connect home devices to the home Wireless LAN.

One could call this “wireless local area network as a service” (WLANaaS) or refer to a “plug-and-play” or abstracted wireless local area network model. In any case, it is ultimately very convenient for the household.

Although ISPs don’t usually advertise their products as home LANs, that is what they are. Some types of ISP services talk about using the modem as a “gateway” to the Internet, which implies that your WLAN is on the other side of that gateway. Users of home WLANs are more frequently connecting devices such as phones, televisions, computers, and printers to evolved WLAN systems where the ISP will offer some type of dashboard visualization for the WLAN in question.

As the IoT paves the way for advanced connectivity, the WLAN provides that “subnetwork” and the convenience of local Wi-Fi operation.

What is Wi-Fi and how does it work?

Wi-Fi is the wireless LAN technology that uses the IEEE 802.11 standards and nothing else. Through the years, different evolutions of Wi-Fi have emerged, culminating in the new 802.11ax standard.

Each version of the 802.11 standard is written for compatibility with 802.3 Ethernet. This is the most common LAN type because Wi-Fi typically extends the edge of a wired network. Peer-to-peer Wi-Fi is also written into the 802.11 standards, and it frequently works in parallel with full-blown WLAN deployments. A common example is wireless printers.

Wireless access points (WAPs or simply APs) act as Layer 2 bridges between 802.11 and 802.3 standards in enterprise networks. Wireless routers in a home network have an AP built-in under the hood. A client device wirelessly connects to the network through an AP.

Is Wi-Fi a wireless LAN?

Wi-Fi networks are Wireless LANs. But the important nuance is Wi-Fi is not the only type of WLAN.

Wi-Fi is pretty much the only Wireless LAN that services human clients directly, although in-building cellular may qualify as well. Most other WLANs likely service headless client device nodes.

Difference between WLAN and Wi-Fi

Although the terms WLAN and Wi-Fi are used interchangeably, the two wireless technologies differ. Wireless LAN uses radio technology to connect nodes, while Wi-Fi is a type of WLAN.

To tackle the generic Wireless LAN construct, though, we first need to review what the local area network means.

A LAN is generally a network contained within a building or campus, representing a geographical or functional construct usually connected via cabling of various sorts. Add a W to LAN, and it becomes a wireless LAN. Wireless technology either extends the LAN, replaces parts of it, or both.

A Wireless LAN can be built on various wireless technologies, including Wi-Fi, cellular, and Bluetooth, for example.

Wireless LAN architecture

Stations

Stations are components that connect wirelessly to networks. They are either access points or endpoints, each identified with a unique network address.

Basic Service Set (BSS)

A BSS is a group of stations that connects to the network. In ad hoc networks, the group of stations is called an Independent BSS (IBSS). A set of connected BSSs, as in a network with multiple access points, is called an Extended Service Set (ESS).

Distribution system

The distribution system connects access points in an ESS. The connections can be wired or wireless. A wireless distribution system (WDS) can use mesh or its own WDS protocol. Fixed wireless is a specialized form of radio transmission for connecting a geographically distant access point.

Access point

The access point is the base station that serves as a hub to which other stations connect. The “access” is that of the stations to the network, but it may also mean internet access, since many routers double as internet modems. In an ESS, access points may be connected with Ethernet cables or wirelessly.

Bridge

The bridge is used to connect a WLAN to a LAN or to an access point.

Endpoint

The endpoint is any end-user station, such as a computer, mobile device, printer, or Internet of Things (IoT) device.

How to create a Wireless LAN

Those who create networks of any sort for a living know network design needs to enable operational goals. When a WLAN presents the right paradigm to achieve specific goals, a qualified network engineer or architect considers which components and technology work best for a given situation. Wireless technology might be part of a wire-intensive topology, or it might be the dominant technology in play.

Creating a Wireless LAN is an exercise in requirements, product and technology selection, and implementation, which can yield a range of final system topologies.

Here are the primary steps to create a WLAN:

Gather requirements. What problem do you want to solve? What applications do you want to enable?
Identify which client devices will be used and their operational needs. Building sensors have different power, security, and bandwidth requirements than tablet PCs, for example.
Identify the right WLAN products, and evaluate which underlying LAN connections and wiring the network needs.
Design the WLAN layout. Ideally, a wireless professional does this.
Install the WLAN components.
Verify wireless coverage and performance.
Verify the design meets operational requirements.
Identify a system owner responsible for updates, troubleshooting, and lifecycle replacements.

How to configure a WLAN

Here are two ways to configure a Wireless LAN:

Infrastructure

A home or office Wi-Fi network is an example of a WLAN setup in infrastructure mode. The endpoints are all connected and communicate with each other through a base station, which may also provide internet access.

You can set up a basic infrastructure Wireless LAN with just a few parts: a wireless router, which acts as the base station, and endpoints, which can be computers, mobile devices, printers, and other devices. In most cases, the wireless router is also the internet connection.

Ad hoc

In this setup, a WLAN connects endpoints such as computer workstations and mobile devices without the use of a base station. The use of Wi-Fi Direct technology is common for an ad hoc wireless network. An ad hoc Wireless LAN is easy to set up and can provide basic peer-to-peer (P2P) communication.

An ad hoc WLAN requires only two or more endpoints with built-in radio transmissions, such as computers or mobile devices. After adjusting network settings for ad hoc mode, one user initiates the network and becomes visible to the others.

Benefits of WLAN

The use of any wireless technology can empower enterprises in many discrete areas. WLAN, specifically, includes the following advantages:

Client device portability and mobility enable new workflows.
Network engineers can build networks virtually anywhere using the right WLAN technology.
The reduction of physical wires and associated pathways saves network costs.
Moves, adds and changes to the system are generally easier than with wired connections.
Network teams can address short-term, temporary networking needs more easily.

Challenges of WLAN

Trading one technology for another presents both advantages and disadvantages. Despite WLAN’s benefits, network teams have to consider the following realities:

Wireless technologies of every sort are subject to interference on the radio waves in use.
Proper WLAN design and implementation require specific skills.
WLAN networks and client devices can have varying feature sets.
Many proprietary, nonstandards-based technologies are available that can be challenging to support.

How secure is a WLAN?

A Wireless LAN is more vulnerable to breaching than a physical network. With a wired network, a bad actor must gain physical access to an internal network or breach an external firewall. To access a WLAN, a bad actor must simply be within range of the network.

The most basic method of securing a WLAN is to use MAC addresses to disallow unauthorized stations. However, determined adversaries may be able to join networks by spoofing an authorized address.

The most common security method for a WLAN is encryption, including Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA), with WPA2 as the standard authentication method.

How does roaming work on a WLAN?

For any sized network, access points can extend the area of access.

Wi-Fi standards are designed to allow a nonstationary user’s connection to jump from one access point to another, though some users and applications may experience brief dropouts. Even with nonoverlapping access points, it pauses a user’s connection until it makes a connection with the next access point.

Additional access points can be wired or wireless. When access points overlap, you can configure them to help optimize the network by sharing and managing loads.

Which is better: WLAN or Wi-Fi?

On the surface, it might seem silly to ask whether WLAN or Wi-Fi is better, given that Wi-Fi is itself one flavor of WLAN.

But, as ubiquitous as Wi-Fi has become, network teams might find Wi-Fi isn’t always the best choice when they need a WLAN. For general-purpose user access, Wi-Fi continues to be the de facto standard. But, where an increasing number of IoT and headless devices are concerned, teams are likely to choose from better WLAN choices.

References

Cisco

Tech Target

Techopedia