(Guide) How to improve your home wifi performance

Introduction

It’s not hard to find wireless router in any residence nowadays. With widespread broadband internet, it’s now more convenient than ever to have internet access everywhere inside a household. However, with the common usage of wireless router as well as the lack of knowledge when such device is used, it creates problems that affect many users. Problems such as signal interference, poor wireless reception, slow network speed, frequent network drop out etc. are not uncommon. As such, this post focuses on addressing the issues that lead to poor network performance. It will then give recommendations on how to make home networks faster, by either make sensible changes to router setup, or give useful guides for any user who want to upgrade/buy new routers.

Note: This post serves as a summary (therefore make a lot of references) to many articles from www.smallnetbuilder.com . SmallNetBuilder is a great website where you can find many thorough reviews of networking equipment as well as guides and tips on networking related subject. Do check them out :)


Some background

Wireless channel basic

Most modern wireless network are based on IEEE 802.11 standards, marketed under the more famous Wi-Fi name. In most regions in the world, there are 13 wireless channels available in the 2.4 GHz band (there are 5GHz band as well, but I won't go into much detail in this post). Each channel is separated by 5MHz from the nearest channel and the often agreed width of each channel is 20MHz.

 
Wireless channels on 2.4GHz band

Wireless channels on 2.4GHz band

 

As seen from the figure above, due to the way each channel in the 2.4GHz channel ‘spread’, only channel 1, 6 and 11 are non-overlapping.

With the implementation of 802.11n standard in 2009, routers and devices can expand channel width to 40MHz, doubling the channel width (from 20 MHz) and providing double the data rate. Currently, devices using 802.11n standard are extremely common and are widely used. Meanwhile device using newer 802.11ac standard is on the rise in term of popularity.

Different from theory, the energy transmitted is not simply contained within a single 20MHz band as stated above. It looks more like this for each channel.

 
Simplified frequency spectrum of wireless channels

Simplified frequency spectrum of wireless channels

 

This figure above illustrate how transmitted power of each channel is 30dB below the maximum power at +/-11MHz away and 50dB below at +/-22MHz away from the centre frequency.

The 802.11 standards also states that all Wi-Fi devices must use "positive acknowledgement” protocol, in the sense that each data packet that is sent must be explicitly notified back to the sender by the receiver. The sender will try sending repeatedly the same packet if such notification is not returned. When a timeout limit is reached, the sender will stop and drop connection.


Co-channel and overlapping channel

When two networks are on the same channel i.e. co-channel, each network will accordingly wait in turn for the other network’s data to pass. However, when two networks are on overlapping channels, the signal in each network will appear as interference on the other network, which will lead to severely degraded performance.


How electromagnetic radiation propagates

As a basic for electromagnetic radiation propagation, signal ‘quality’ and strength decreases inversely proportional to the square of the distance between the receiver and transmitter. Additionally, walls, floors, and furniture can block or reduce signal’s strength and quality that passed through them and can be considered as obstacle.

The antennas used on wireless networking devices are crucial in determining how the signal propagates. A lot of wireless networking devices come with omni-directional antennas, which propagates signal in all directions. On the other hand, many routers that come with external antennas do have some 'directional' in term of how the signal travel through space.


Other interference sources and their impact

Beside interference from other wireless networks from overlapping channels, other devices that operate on similar frequency bands can interfere with wireless networks signal as well. Following are some of the more problematic devices that are commonly used: Cordless phones, microwaves and any Bluetooth devices.

The interference caused by these devices varies from minimal, that only cause minor slowdown in performance, to creating complete havoc in Wi-Fi networks. An paper was published in 2008 title ‘The Effect of Interference on General WLAN traffic’ has shown that Bluetooth headset can slow down your network performance by almost 20%, while microwave can reduce the speed by more than 62%. Worse than that, interfering wireless network can cause 89% reduction in performance and the worst come when a cordless phone is used, which can cut off your wireless network completely.


Common issues

This post will only discuss about the two most common problems regarding wireless networking in common household. This include slow performance and small area of coverage.


Slow network performance due incorrect setup

The issue of wrong channel setup is extremely common in residence area. Following is a screenshot from a channel analysis conducted in a condominium where every single flat has their own wifi network.

 
An incorrectly configured wireless space

An incorrectly configured wireless space

 
 

As can be seen from the image above, there are many wireless networks that run on different channels that is not centred on channel 1, 6 or 11. A few channels are even spanning 40 MHz of channel width.

When two channels are located right next to each other (for example one on channel 1, another on channel 2), they would overlap as shown below.

 
Two overlapping channels

Two overlapping channels

 

The above figure is showing the amount of signal get overlapped (shaded area) when 2 channels are set to 2 nearby channels. Since there are so much interference, communication of both channel will severely degrade. This is different from the case shown next.

 
THREE non-overlapping channels

THREE non-overlapping channels

 

It can be easily seen that the amount of overlapped power from channel 11 to channel 6 in the figure above is much less than the previous example.

In general, only channels 1, 6 and 11 are considered non-overlapping channel in the 2.4GHz band only. This is because even though in theory they do overlap, but the effect of such overlap is negligible.

And now is the problem, not all routers are pre-configured by the manufacturer to be used in 20 MHz mode on channel 1, 6 or 11. Moreover, most users who say they ‘know’ how to configure and overdrive their routers are not aware of this channel interference problems. Most think that it’s the best to set their router to operate on an ‘empty’ channel. As such, these actions always result to congested wireless space that can be easily observed in any residence area.


Low coverage

It’s quite common to find that the location of router in a household is not optimised. Most of the time, the router position strongly depends on the position of outlet of the broadband cable in the house. It’s also not hard to spot routers that are placed at the corner of the house, under table or even hidden behind furniture etc.


Possible solutions

For slow wireless network

Many Windows users mistakenly use the value displayed in ‘Wireless Network Connection Status’ to be the actual speed of the connected network. However, this is not the case. In fact, this number only reflect the link rate that is currently being used, it don’t reflect in anyway the actual throughput of the network. As such, don’t use such method to determine network’s actual speed.

To determine the actual throughput, the 'easiest' way is to transfer some large file (like movies) from another computer to your computer over the internal network. This method will give you a rough idea of how fast/slow your device's wireless performance over the wireless/wired network.

You can analyse wireless environment around you using MetaGeek’s insider program or other similar programs to show all networks in range, channel overlap and each channel strength. User can use this program to walk around the house to determine weak spot in term of network coverage. By using this program, user can choose which channel (1, 6 or 11 only) to set their network. The better channels are those that don’t have strong presence of other networks on the same channel as well as little interference from nearby channel. Again, only channel 1, 6 or 11 should be selected.

 
A properly configured wireless network space (BTW: NTUWL is the name of a wireless network)

A properly configured wireless network space (BTW: NTUWL is the name of a wireless network)

 
 

Regarding security settings of your router, just use WPA2 with AES security protocol. Any other type of encryption or protocol such as WEP or WPA/WPA2/TKIP will reduce wireless network performance and make your network less safe. A long password for your network is recommended as well. Try to use more than 10 characters of different type (lower and upper case alphabet, number) if possible.


For low network coverage

The easiest method to improve network coverage is to locate wireless router to the place where you need wireless coverage the most. Or to make thing even simpler, the best place to locate a router in a house is at the centre of the house itself. However, sometimes this cannot be done since it is heavily dependent on the location of broadband outlet in a household.

To address this problem, we can either relocate the position of the broadband outlet, or setup the router (to its best position in the house) away from the modem (in which modem’s location cannot be changed easily). To connect the router to the modem, Ethernet cable RJ45 can be used, or power line networking products can also be used.

Once the general location are chosen, the following guidelines will help with the exact position where you should put your router:

  1. Higher is better than lower.
  2. Never put inside any object.
  3. Away from large metal objects.

Besides relocating the router to a better position, many users think that improvements can be made to the router itself. These are a few common, but not really helpful methods to do so:

  1. Boosting transmit power and upgrading antennas
  2. Upgrading router

As strange as it may show, boosting transmit power and upgrading antennas are the least effective. As stated in the background section of this post, these 2 upgrades will only improve the router side of the problem. Since the devices that are connected to the router remain the same in term of transmitting power, not much to none improvement in term of coverage can be observed.


As for buying new gear, there are a few guidelines that you should follow:

Follow, don’t lead

It’s has been observed that newest routers with all the advertised newest technologies don’t usually improve network performance and coverage that much or at all. Partially one of the reason is that the products have not been through thorough testings and updates, firmware ran by these newest routers are usually not optimised and contains several bugs. Moreover, once again user need to keep in mind that it’s not always about the router, it’s also about the devices that connect to the router. They need to have compatible clients that can utilise all those newest technologies for its advantages. By upgrading the router alone without upgrading their clients, performance improvement is not always guaranteed.


Understand what you are buying

By understand what you are buying, your chances of being disappointed on your investment is much reduced. Moreover, with more knowledge on the device, you can make smarter decision on which router to buy, or even if you need to buy a new router or not.


Your budget

Always buy the best router that you can get within your budget. Don’t go for too cheap routers that are too good to be true though.

In my opinion, I would recommend the following routers to anyone who need a upgrade.


Choose best router types

As mentioned, router that use 802.11ac standard is on the rise and this is what you should go for at the moment. The technology is matured enough and is becoming well spread in term of implementation in laptops and mobile devices.


Conclusion

Wireless network and router have made tremendous impacts on our life. To not take thing for granted and to make your existing network performance faster, just take note of the following tips:

  • Determine and understand network problems before starting configuring it.
  • Use channel 1, 6 or 11 on the 2.4 GHz band ONLY.
  • Cordless phones, microwaves, and other 2.4 GHz devices can cause interference.
  • Use WPA2/AES encryption protocol is better both in term of security and performance.
  • Location, location, location of your router is very important. It’s a good advice to locate it at the centre of the house.
  • When all of the above methods doesn’t give you satisfy results, consider upgrading your router, preferably one that use 802.11ac standards. However, don’t buy the most expensive routers being sold out there.
  • Upgrade client wireless’ devices if possible. 

There are a lot more way to improve a wireless network performance, but those will require a lot more understanding and expertise to be carried out. I hope this post will help you improving your home network. Give us your feedback and I will see you in the next post of TFO.

 

OTHER REFERENCES

Farpoint Group. (2008, January 31). The Effects of Interference on General WLAN Traffic. From http://www.cisco.com/c/dam/en/us/solutions/collateral/enterprise-networks/rfsolutions/net_implementation_white_paper0900aecd805eb8a5.pdf