The need for more international communications capacity driven in part by the growth in access to cloud services including those using artificial intelligence has led to the continued expansion of the mesh of submarine cables that encircle the world.

For example, the new Medusa subsea cable will thread through the Mediterranean connecting Lisbon with countries such as Spain, Morocco, Tunisia, Malta, Libya, Algeria, and Egypt. The cable will contain 24 optical fibre pairs each carrying 20 Terabits per second for a total system capacity of 480 Terabits per second.

Google, meanwhile, has announced its intention to deliver another high capacity transatlantic cable linking the USA with Bermuda, the Azores, and Spain.

PTT’s new online course “Optical line systems” explains the principles of the technologies that enable these high capacity, low latency connections. The course also gives up-to-date information about the capabilities, components and operation of the optical links that provide interconnections for telecommunications and cloud service providers over land as well under the sea.

Just when you were getting used to the benefits of 5G – at least if you are lucky enough to have 5G coverage in your area – steps are being taken for the development of 6G.

3GPP, the body responsible for setting international standards for mobile technology, recently convened a plenary meeting to discuss future developments. The subjects addressed by participants included the development of enhancements to 5G Advanced services and the preparation for a smooth transition to 6G.

There are two schools of thought as to how big a transition there should be. Some network operators are, perhaps understandably, arguing for an evolutionary approach to avoid expensive hardware changes. Instead, they suggest that upgrading existing mobile sites for 6G services should be possible by just software changes.

Others are calling for the European Union to reserve the upper 6 GHz radio band for just 6G services. Operating at these super high radio frequencies (SHF) offers increased download speeds but over a restricted range. However, this would require investment in new radio equipment.

So, when can we expect access to 6G? In the past a new generation of mobile service has been introduced every ten years. 5G services have been available since 2019. Based on past experience, therefore, we have another four years to wait. It also takes on average 20 years from launch for a new generation to becomes predominate over older services. Meanwhile, we can look forward to enhancements to 5G services and an expansion of coverage.

You can keep abreast of mobile technology development by studying PTT online courses including “4G and 5G radio access networks” and “Advanced mobile systems“.

The UK is to become the first country in Europe to ban SIM farms in a measure to assist in the protection of consumers.
SIM farms are electronic devices that are capable of simultaneously using many SIM cards (subscriber identity modules) to send SMS texts or phone calls in large numbers over the telecommunications network.

The aim of the UK government is to clamp down on the sending of scam calls or texts by fraudsters. So-called phishing messages can be used to lure recipients in giving away personal or financial information. Vodafone UK has reported it has blocked more than 73 million suspicious texts in 2024 alone. The proposed legislation will assist is stemming the flow of these messages.

SIM farms can also be used to fraudulently drive traffic to a premium rate telephony service (PRS) run by the criminal. For example, the fraudster may automate very short calls from the SIM farm to victims which will not be picked up in time. Having noticed the “missed call”, people may make a call to the PRS through the SIM farm without realising it is charged at the premium (very high) rate.

In the past, SIM farms containing fraudulently obtained SIM cards were used by criminals to terminate international calls that bypassed the PTSN (public service telephone network) and so avoided high international call charges. The low cost service was advertised to potential users in other countries primarily through the sale of international calling cards. Of course, the widespread use of free VoIP services such as WhatsApp has now made that fraudulent activity redundant. But as always, criminals have moved on by exploiting advances in technology and services for new ways of defrauding the unwary.

PTT’s online course “Telecommunications systems security” explores ways of reducing the vulnerability of telecommunication systems and databases to security breaches and fraudulent misuse.