Vodafone is being investigated over its ‘Vodafone Passes’ bundle, which allows customers to stream music or video without affecting their monthly data allowance, while Three is being investigated around whether it should be allowed to restrict tethering and prevent its customers using mobile phone SIM cards in their tablet devices.

Net neutrality is bound by the Regulation on Open Internet Access (ROIA), which is intended to stop providers from prioritising one service over another, or blocking them entirely.

Throughout the industry, mobile operators such as Three, Virgin Mobile, and EE have been striking deals with the likes of Netflix, Twitter, Apple, Spotify and many other content providers, in order to meet consumer demand and bolster revenue streams. Generally, these deals, known as ‘zero-rated’ services, allow consumers to use such services without eating into their capped data plans.

However, the question is: ‘Do these deals therefore imply certain privileges for certain services over others?’ Traffic management for the mutual benefit of all consumers is of course acceptable and, indeed, desirable, particularly when it comes to roaming overseas. But shaping traffic for commercial reasons is not under the ROIA.

EU net neutrality regulations do not prohibit the zero rating of services, and does not result in any throttling or prioritisation of services, but the argument is that such deals could incentivise consumers to use one service over another.

Arguably, In Vodafone’s defence, it stated that it was “very disappointed with Ofcom's decision to target Vodafone Passes," according to the Financial Times. The operator noted that it had been in regular contact with Ofcom over adherence to net neutrality legislation.

However, it did say that, while it does not throttle services for customers when roaming, it may ‘optimise’ these services by, for example, reducing the quality of the stream.

The results of the investigation, and a wider report on net neutrality compliance in the UK, are expected from Ofcom in June, and it will be interesting to see its findings, which could have a significant impact on how operators bundle their deals and offer streaming services in future. If found guilty, Vodafone and Three could be fined up to 10 per cent of their annual earnings. Watch this space.