Overall fixed wireless considerations

Fixed wireless technologies are always dependent on one aspect above all others - signal. Signal is the content being sent via wireless communication, such as text, voice, video, or data.

The 3 key principles of any signal are:

Signal strength

How powerful it is sent and received. The more powerful, the further distance it can reach or its ability to penetrate through obstacles can be.

Signal quality

How clear the signal is once received. Signals can face interference from external influences, such as other radio sources, environmental factors etc.

Reliability

How constant the signal is. Is there something that blocks the signal for periods of time? Environmental conditions such as weather or physical factors such as traffic or even trees swaying could reduce the signal or even block it completely. With any wireless solution it is common to have an agreement for a minimum and maximum throughput, but it can be expected that the data rate will fluctuate between these two. 

When deploying or implementing fixed wireless technologies you should consider the following points in order to maximise the chance of receiving a reliable connection:

Antennae

The key components of any successful fixed wireless implementation are the antennae. Antennae can be omni-directional (transmitting, and receiving the signal in all directions, such as radio antenna) or uni-directional (designed to transmit or receive in a specific direction such as microwave antenna). 

Generally, antennae that are fixed to any building should be as high as reasonably possible in order to clear any obstructions and reduce interference from objects whilst remaining accessible for maintenance. Cabling to the antenna for both power and data needs careful planning and should include provisions for redundancy, for example dual/diverse cabling. 

Critical to the deployment of any fixed wireless solution will be surveys of the locations of the antennae as well as radio interference. A survey should be undertaken by the installer to provide a clear view on the suitability and nature of an installation and the expected performance.

If the antenna is outside, it will be subject to weather conditions. Wind loading and ice build-up are of particular concern. Antennae can have countermeasures to protect against ice build-up including additional ice guards or internal heating elements that turn on when a temperature drop is detected. Wind loading can be assessed as part of the survey and specific recommendations given. 

Weather conditions can have significant impact on data rates and signal quality. Rain and snow are of particular concern. 

Wildlife, particularly birds are attracted to external antennae for nesting/roosting. In addition, their activities can lead to corrosion of exposed metal components. Not only could they impact signal quality but can cause issues with neighbours over detritus and noise. In some exceptional cases, specialist bird scarers, or passive protection (netting, spikes) may be suggested. 

Permissions installing external antennae (or internally where alterations are required) may need written permission from building owners or managers and external bodies, such as councils for planning permission, listed building consents etc. Legal advice may be required before proceeding with an installation.

Line of sight

Some fixed wireless solutions (but not all cellular does not require it) require a clear and unobstructed 'line of sight' between the site’s antenna and connecting antenna. Anything that could block this line-of-sight, including structures or buildings, hills and other topographical features, could result in interference leading to poor or no signal. 

Security

Any fixed wireless implementation will bring its own security considerations that must be assessed locally.

Common security considerations

As the signal could be picked up by anyone then additional countermeasures such as encryption and enhanced authentication should always be used. The most common way to achieve this is by setting up a 'site-to-site' Virtual Private Network (VPN). A simple example of this is where a firewall at the remote site connects to another firewall in the datacentre to create an encrypted 'tunnel' through which the data passes.

Denial of service via physical disruption (disrupting the network link) is a greater risk than with fixed line connectivity. If the antennae require line of sight to operate then anything that obstructs this may block or weaken the signal. Also, as the most effective antennae are mounted outside, there is also a risk of them being stolen or vandalised.

Review the Data Security and Protection (DSPT) Toolkit. This is an online self-assessment tool that allows organisations to measure their performance against the National Data Guardian’s 10 data security standards. As data security standards evolve, the requirements of the DSPT are reviewed and updated to ensure they are aligned with current best practice.

Refer to Cyber Essentials. This is an effective, government backed baseline scheme that will help you to protect your organisation, whatever its size, against a whole range of the most common cyber-attacks.

Potential for additional costs should be taken into consideration when procuring fixed wireless connectivity, particularly if it is likely to be a unique or limited deployment. Maintenance, management, licencing, training, support, and integration costs should be well understood prior to deployment.

Where possible it is always good practice to ensure that any contractual arrangements for different forms of connectivity at sites are co-terminus. In the event of a site closure or change of network supplier this will help avoid additional costs and complexity.

The cost and availability of replacement equipment and ability to upgrade equipment should be taken into consideration, particularly for items of equipment that are mounted outside and have increased risk of damage as a result.

In some circumstances managing another connectivity supplier in addition to your mobile and fixed line operators will be necessary, particularly for some services that are sold direct by operators.

Service Level Agreement (SLAs) should be understood and recorded in any service management system, particularly for unique or limited installations (in comparison to the rest of the estate). It is also helpful if the personnel on site understand the expectations around the service and any SLA’s.