How to Install and Configure a Wireless Network

How To Set Up A Wireless Network

• Determine network requirements;
• Conduct site survey;
  • Go to the install site.
  • Bring test wireless access points.
• Use wireless analysis software to determine antenna placement;
  • Use in conjunction with building blue prints.
  • Receives radio signals.
  • Visual the different rages each wireless access point (WAP) will cover
• Determine dead spots/WAP limits
• Select antenna type

WAP Placement

• Needs to be in a spot that can provide coverage to a large area. You want it high in a room, free from obstruction;
• Placement is critical, especially with WAP2
• Overlapping WAPs have the same SSID
• Set up WAP to have a 10% overlap of each of their ranges
• When we have wireless access points that over lap, we dont want their channel bands to overlap, if channels overlap, you have connectivity issues. You want to use channels 1/6/11
• Sometimes we want to reduce the gain of an antenna in order to reduce the overlap or broadcast area

What are the Different Wireless Antenna Types

• Play a strong role in setting up WAP
• Provide different signal patterns and gain.  Gain is the amount of power put out by the antenna to push out a signal.   An unlimited power source does not mean limited gain.  Wireless coverage is limited by reaches of the frequency we are using, not just the power coming to the WAP.
• Different antenna types help focus the wireless waves.

Omnidirectional Antenna

• Broadcast signal is equal in all directions;
• Used in small offices/home;
• Often only one WAP; and
• The key is that it should be in a high central location so the signal spreads.

Unidirectional Antennas

• Point signals in a single direction;
• Useful to cover an angle of an office;
• Useful for connecting two wireless access points together;
• Allow us to push our wireless signal further as the signal is concentrated and interference is less of an issues; and,
• Not good in a home or small office environment.

Understanding Wireless Interference and Frequencies

Because wireless networks communicate via radio waves, it is important to understand the different frequencies and how they are susceptible interference, especially if they are on the same bands as other nearby radio frequency/electromagnetic energy emitting devices that deform our waves such as:

• Microwaves
• Cordless phones
• Baby Monitors
• Other Wifi Networks

Interference can be mitigated by changing frequency or upping the gain on your antennas.

• 2.4 GHz band is crowded; lots of devices run in this band and cause interference.
• 5.0 GHz is less crowded

Frequencies

2 Major bands
A frequency is a electromagnetic radio wave. Hertz is the number of waves per second, the higher the number, the more waves per second. As wave encounter object, those that have a lower frequency (2.4GHz) and spread further apart pass through obstacles with greater ease than higher frequency (5GHz) waves, so they travel further.
We call these waves bands, because each band has channels (sub frequencies) within them. When we go into our access settings for the WAP, we can select channels that have less traffic, so say for example channel 6, which is actually 2.473 GHz

The 2.4 GHz Band

The 2.4GHz band has a longer range than 5 GHz and 14 channels total, but not all are available for use for two reasons:

• Regulation – The available channels vary depending on where you are in the world. In the United States channels 12, 13 and 14 are not allowed for Wi-Fi; 14 is used for government/military purposes and the others are used by TV and satellite services. In the rest of the world, channels 1 through 13 are generally usable, and in a few places channel 14 is available.
• Channel overlap – Neighboring channels overlap, so they aren’t all usable at the same time as each channel has a width of .22 GHz (as seen in the image below). You always need at least a 2 channel gap on either side. Channel 1 overlaps with 2 and 3, channel 6 over laps with 4,5,7,8 and channel 11 overlaps with 9,10,12,13. If you look at the image below, you will see the gaps between the channels. Routers auto-negotiate the channels they are using, but if we pull our our wireless analysis software, we can manually over ride these channel settings. If you are getting some interference, you can move onto the channel that is interfering with you as a way to reduce the interference

Regardless of regulations, the best channels to use for 2.4GHz band equipment are channels 1, 6, and 11 as it minimize interference caused by partially overlapping Wi-Fi signals:

2.4GHz Channel Interference

You can use any Wi-Fi channels, as long as they are 5 channels apart but may not be ideal, as channels 1 and 2 would be left unused, and in many places in the world channel 13 is not available.

The 5GHz Band

• This band can transmit more data per radio wave;
• Is more expensive than 2.4GHz;
• As this band spans from 5 GHz to 6 GHz, it provides for more channels than the 2.4GHz band. Some of the channels are restricted as the channels can interfere with radar channels, so it is best for it to auto negotiate; and,
• Cover less distance than 2.4 GHZ

What Are The Different Wireless Standards?

Wireless networking gear is cursed with an array of choices and abbreviations.  First released in 1997 and governed by the IEEE 802.11 standard which initially supported a paltry maximum network bandwidth 2 Mbps, too slow for most applications., Wi-Fi standards have continually evolved, resulting in faster speeds, further coverage and…. news name to identify the standards; these new standards were known by their amendment (802.11b, 802.11g, etc.).  The most important thing to remember here is that both the WAP and the wireless NIC have to be working on the same standard for the network to work.  Being an unregulated frequency, 2.4 GHz wifi devices can have interference from microwave ovens, cordless phones, and other appliances using the same range. which can be minimized by installing 802.11b devices an adequate distance from other appliances.

In what was described by some as an outbreak of common sense or blinding flash of the obvious, 2018 saw the Wi-Fi Alliance took steps to make Wi-Fi standards names easier to identify and understand.  Wi-Fi 4 is 802.11n, Wi-Fi 5 represents 802.11ac and 802.11ax becomes Wi-Fi 6.

How does Wireless Compatibility Work

Compatibility is determined by the NIC and the WAP; they need to support compatible standards and will run at the lowest speed allowed. 

How do I find out my NIC wireless standard? 

On a Windows machine, run the command “netsh wlan show drivers” and what you will see is a listing for “Radio Types Supported” that outline the drivers for the interface card.

If we just want to support a single standard, all the NIC’s being used must be on that standard.

802.11b Wireless Standard

IEEE expanded on the original 802.11 standard in July 1999, creating the 802.11b specification. 802.11b supports bandwidth up to 11 Mbps, comparable to traditional Ethernet and had a range up to 150 feet.   The 802.11a amendment to the standard was released at the same time as 802.11b and introduced OFDM (orthogonal frequency division multiplexing) a more complex technique for generating the wireless signal. 

802.11b uses the same radio signaling frequency  as the original 802.11 standard. Vendors often prefer using these frequencies to lower their production costs and the signal range is good and not easily obstructed. The downside is that it has the slowest maximum speed.

802.11a Wireless Standard

While 802.11b was in development, IEEE extended the 802.11 standard to 802.11a. As 802.11b  popularity grew faster than 802.11a, many believde that 802.11a was created after 802.11b, but the reality was it was created the same time. Due to its higher cost 802.11a, usually found on business networks while 802.11b  serves the home market.  802.11a offered a few advantages over 802.11b:

• Less prone to interference as it operated on the less crowded 5 GHz frequency band;
• A bandwidth than 802.11b, with a theoretical max of 54 Mbps.

As a trade off,  an 802.11a access point transmitter may cover less than 1/4 the area of a comparable 802.11b/g unit and have more difficulty penetrating walls and other obstructions.

You don’t see many consumer 802.11a devices or routers, as 802.11b devices were cheaper and became more popular in the consumer market and 802.11a was mainly used in business applications.

As 802.11a and 802.11b utilize different frequencies, the two technologies are incompatible with each other.  Vendors who offer hybrid 802.11a/b network gear, simply implement the two standards in parallel, as the connected devices must use either one or the other.

802.11g Wireless Standard

In 2002/3, a new standard, 802.11g hit the market, attempting to combine the best of both 802.11a and 802.11b.  802.11g used the same OFDM technology introduced with 802.11a and supported a maximum theoretical rate of 54 Mbps.The pros of 802.11g are fast maximum speed and signal range is good as it runs on 2.4 GHz.  The cons of 802.11g are that devices costs more than 802.11b and appliances may interfere on the unregulated signal frequency

802.11g:

• Supports bandwidth up to 54 Mbps;
• Uses the 2.4 GHz frequency for greater range.
• Is backwards compatible with 802.11b, meaning that 802.11g access points will work with 802.11b wireless network adapters and vice versa.  The caveat being that in order to run faster, both need to be able to push out data at 54 Mbps, or you get throttled down to 11 Mbsp.

802.11n Wireless Standard

Ratified in 2009, 802.11n (also sometimes known as “Wireless N”) was designed to improve on 802.11g’s:

• Speed by using channel bonding, reaching up to 300 Mbps and up to 450 Mbps when using three antennae;  Channel bonding, used only by 802.11n allows 2 wireless channels to be bonded in a single band spanning 8 channels.
• Bandwidth by utilizing multiple wireless signals and antennas (called MIMO technology) instead of one.
• Compatibility with 802.11 a/b/g by using 2.4 and 5 GHz

802.11n uses MIMO (Multiple Input Multiple Output), which allows multiple transmitters/receivers to operate simultaneously at one or both ends (one antenna exclusively sends data, the other just receives it) of the link to a single device, providing a significant increase in data without needing a higher bandwidth or transmit power.  The cons of 802.11n are that it costs more than 802.11g and the use of multiple signals may greatly interfere with nearby 802.11b/g based networks.  Routers that only support 802.11n are no longer manufactured.

802.11ac Wireless Standard

802.11ac, also referred to as WiFi 5, is the newest generation of Wi-Fi signaling in widespread use, offering speeds ranging from 433 Mbps up to several Gigabits per second.  802.11ac:

• Utilizes dual band wireless technology;
• Supports simultaneous connections on both the 2.4 GHz and 5 GHz Wi-Fi bands;
• Offers backward compatibility to 802.11b/g/n and bandwidth rated up to 1300 Mbps on the 5 GHz band plus up to 450 Mbps on 2.4 GHz;
• Dual bands mean increased cost; still prone to interference on the 2.4GHz frequency;
• Supports up to eight spatial streams (compared with 802.11n’s four streams);
• Doubled the channel width up to 80 MHz;
• Uses beamforming, where the antennae basically transmit the radio signals directed at a specific device; and
• Uses multi-user MIMO (MU-MIMO).  In comparison to MIMO, which directs multiple streams to a single client, MU-MIMO simultaneously directs spatial streams to multiple devices. While not increasing the speed to any single client, MU-MIMO increases the overall data throughput of the entire network.

Wi-Fi 6 (802.11ax)
The newest generation Wi-Fi standard is Wi-Fi 6 and offers improvements similar to 5G.

• Avoids traffic congestion in public spaces;
• Offers higher data rates and capacity to 9.6 Gbps;
• Offers better 2.4 GHz and 5 GHz spectrum support;
• Offers increase in multi-user, multiple input, multiple output (MU-MIMO) from 4 x 4 to 8 x 8; and,
• Wi-Fi 6 allows one router to handle more antennas which means one router can connect to more devices.

SSID

• Service Set ID.  We can have multiple routers with the same SSID;
• Identify wireless name;
• To improve security, turn off SSID broadcast.   This means SSID’s must be added manually; and,
• Change from default.