Network Testing and Auditing

Network testing and auditing are essential to understanding the reliability, security, and overall performance of an existing network before making upgrades or introducing additional equipment. This process should include a review of routers, firewalls, switches, wireless controllers, and other core network devices to establish whether they are still supported, capable of meeting current demands, and suitable for future expansion. It is also important to determine whether these devices can be managed remotely, allowing engineers to monitor performance, diagnose faults, apply configuration changes, and respond to issues without needing to attend the site physically. Firmware and security updates should be reviewed to ensure devices continue to receive essential patches and remain appropriately supported, helping organisations maintain security and meet relevant compliance requirements, including those associated with payment card environments such as PCI DSS where applicable.

 

Network segmentation is another critical area to assess. Using VLANs, firewall rules, and appropriate access controls can separate business-critical systems, payment terminals, CCTV, staff devices, and guest Wi-Fi traffic. For example, guest wireless networks should be configured to prevent guests from communicating with one another or accessing internal network hardware and business systems, while still allowing controlled access to the internet. Simply creating separate VLANs is not enough on its own; routing, firewall policies, and client isolation must also be configured and tested to ensure the intended separation is enforced.

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A review of the physical network infrastructure is equally important, particularly the backbone cabling that connects network cabinets, switches, floors, and separate buildings. Older copper and fibre cabling may impose limitations on the speeds that can be achieved, and existing links should be assessed to determine whether they can support increased bandwidth demands as more users, access points, CCTV cameras, and other devices are added. Testing should identify potential faults, damaged cables, poor connections, link-speed limitations, and bottlenecks that could affect the performance of the wider network. Resilience and disaster recovery should also be examined to establish what backup connectivity is available if a cable or network link fails, whether failover is automatic, and whether the backup can provide sufficient capacity to keep essential services operating. For example, having two spare fibre cores available within the same cable between two buildings does not necessarily provide meaningful physical resilience. Although those spare cores may allow a failed fibre pair to be replaced if the fault is limited to the fibres in use, damage to the cable itself, such as accidental excavation or a cable cut, could disable all the cores simultaneously. A more resilient solution may involve a second fibre connection routed through a completely different physical path, ideally entering the buildings through separate routes and using appropriately independent infrastructure. This can significantly reduce the risk of a single physical incident disrupting both connections, however, true resilience also depends on the independence of the wider infrastructure, including ducts, building entry points, provider equipment, switches, power supplies, and upstream network routes. By reviewing and testing the network as a complete system, organisations can identify weaknesses before they cause outages, improve security and performance, and ensure the infrastructure is capable of supporting current requirements and future growth.