Telecommunications is interwoven into the fabric of modern society. We perhaps take it for granted our ability to access online services and communicate electronically with family, friends, and colleagues.
Because of our reliance on telecommunications, any unravelling of the communications webs that serve national and international communities must be avoided. But threats to our ability to communicate take many forms including natural disasters, accidental damage, and malicious actions.

Earlier this year, damage to four subsea cables off the west coast of Africa disrupted internet services across the continent. Cables affected included the West African submarine cable system (WACS). The cause of the disruption is believed to be seismic activity. A year earlier the same cable was damaged with the cause attributed to a subsea landslide.
Just prior to the 2024 WACS disruption, three submarine cables in the Red Sea were damaged, probably by the anchor of a cargo ship sunk by Houthi militants. The Red Sea is a critical telecommunications route, connecting Europe to Africa and Asia via Egypt. The severing of the WACS system at around the same time made finding alternative routes for African traffic more difficult.

In 2023, a gas pipeline and a close-by subsea telecommunications cable stretching between Finland and Estonia were damaged. On the same night, another subsea telecommunications cable connecting Estonia and Sweden had also been damaged.
The cause of these events is clouded by politics and possible subterfuge. At the time a nuclear-powered ship owned by the Russian state was in the area. But to make the situation even murkier a Chinese vessel was tracked accompanying the Russian ship at both locations. Finland has recovered the anchor of the Chinese vessel from near the gas pipeline. Whether the damage to the two cables and pipeline was accidental or malicious may never be ascertained. Both China and Russia deny any involvement.

Because of these threats to International communications, the EU Council has produced a report on the cybersecurity and resilience of Europe’s communications infrastructures and networks. Included in that report is a recommendation that EU member states should investigate the ownership, capacity, resilience, and redundancy of core Internet infrastructure including submarine cables.

PTT’s online courses “Telecommunications systems security” and “Telecommunications infrastructure and administration” discuss how to improve the resilience of the telecommunications systems we all rely on.

Most people on the planet now use some form of communications network as part of their daily lives. We are so accustomed having our phones, computers and many other devices connected to the outside world, when something goes wrong with the network, it can cause a lot of disruption.

When communications networks go wrong, it often creates international news, such as when the telecoms network run by Australian firm Optus went down for almost 12 hours in November 2023. Such outages are rare, but in a connected world, being unable to place phone calls, use the internet, make card payments, use public transport or call the emergency services can be almost disastrous.

Which is why regular network maintenance and fault-finding is an essential task for telecommunications and network engineers. Skilled engineers are able to constantly be aware of potential issues before they arise, work on preventative maintenance and swiftly identify faults and rectify them as they occur.

PTT has two updated online courses covering this topic that are essential for those responsible for the installation and maintenance of telecommunications, local and wide area networks.

The “Telecoms testing and fault finding” course describes how to follow a structured approach to fault finding and maintenance, and the role and significance of the various tests employed on telecommunications networks and broadband connections.

“Network testing and fault-finding” also explains the benefits and methods of following a structured approach to fault-finding and maintenance, and describes the role of the various tests employed on Ethernet/IP networks and their use in fault finding and measuring network performance.

These online courses can either be studied as a standalone course of study by anybody working in the industry or can become part of a structured programme such as an apprenticeship. In the UK, these courses can fulfil certain knowledge objectives in a number of digital apprenticeships, including:
Level 2 Telecoms Field Operative (K9, K10)
Level 3 Information Communications Technician – Network Technician (K3, K9, K25, K28)
Level 3 Information Communications Technician – Digital Communications Technician (K3, K9, K43)
Level 4 Network Engineer (K1, K4, K5, K6, K15, K17)

If you want to discuss this subject with us further, or any training needs, please contact us.

We take it for granted that when we click on a link to visit a web page, we will be directed to the intended web site. But ensuring traffic reaches its intended destination depends on interactions between computers and networks around the world that are operated by many different organisations. And the routing process depends on trust. When network A tells network B that it can provide a route to destination C, network B assumes network A is run by good guys and believes them.

Routes are advertised using border gateway protocol (BGP) messages. In the early days of the Internet, it was a reasonable assumption that those BGP messages could be trusted. But as the Internet has grown, that is no longer the case. Those with bad intent may hijack the BGP system to divert traffic to their servers to harvest information or money. Hijacking BGP routing is analogous to an adversary changing road signs, redirecting traffic under the pretence of leading them to their intended destination.

A BGP weakness was exploited in 2018 to divert traffic destined for a cryptocurrency website to the hijackers’ phishing site on a server in Russia. During the attack, which lasted for two hours, the hijackers stole $150,000 in cryptocurrency. Although the cryptocurrency site relied on Amazon Web Services (AWS), the hijacking was possible without having to attack the AWS or cryptocurrency servers. Instead, the hacker advertised a supposedly more attractive route to the cryptocurrency site to an Ohio-based internet service provider who took the advert on trust and passed it on to others.

Apart from the activities of those with bad intent, human error can also cause significant disruption. In 2021, it was reported that a Vodafone India network mistakenly advertised that it provided routes to thousands of addresses, when it didn’t, causing the internet to flood this network with traffic that was not meant to go through it. This had a major impact on service providers around the world including Google.

There have been many more examples of the disruption caused by incorrect routing in recent years. Various measures to combat the vulnerability of BGP are now available but not all network operators have adopted them.

PTT’s new online course “Exterior IP routing” describes the role and operation of BGP and the security measures that can be taken to protect the global routing system. Its sister course “Interior IP routing” is also available.