The traffic inspection required to operate systems that breach net neutrality principles and prioritise some content over other content could violate privacy and data protection rights, he said.
Peter Hustinx said that EU telecoms regulators should monitor whether ISPs are complying with EU data protection and privacy laws when managing communications across their network. Net neutrality is the principle that an ISP will deliver all content requested by a customer equally, not allowing content producers which pay it to have preferential access to its subscribers.
Hustinx called on the European Commission to establish an expert group, comprised of regulators and privacy watchdogs, which would "develop guidance" on applying the principles of data protection and privacy to net neutrality "in order to ensure solid and harmonised approaches and the same playing field" across the EU.
He said the guidance was necessary because of "the relative novelty of the possibility of massive, real-time inspection of communications" by ISPs in delivering services. Findings of the group and regulators could determine whether further EU regulation of net neutrality is needed, Hustinx said.
ISPs sometimes block or slow down users' access to some content during busy periods on their networks, but can also benefit from this kind of "traffic management" by charging content providers who are willing to pay for preferential access to their subscribers or by charging users more for fewer restrictions. To decide which content to "throttle" or block access to ISPs sometimes inspect personal data contained in communications. Hustinx said that this activity can be legitimate providing it complies with EU law.
"The concept of net neutrality builds on the view that information on the internet should be transmitted impartially, without regard to content, destination or source," Hustinx said in a statement. "By looking into users' internet communications, ISPs may breach the existing rules on the confidentiality of communications, which is a fundamental right that must be carefully preserved. A serious policy debate on net neutrality must make sure that users' confidentiality of communications is effectively protected."
EU rules around net neutrality have not been explicitly written into EU-wide Directives, but recent changes to the Framework for Electronic Communications Directive set out certain requirements for national regulators to promote the concept.
Under the Directive EU member states must ensure that national regulatory authorities "take all reasonable measures" proportionate to "promote the interests of the citizens of the European Union by ... promoting the ability of end-users to access and distribute information or run applications and services of their choice".
Other rules set out in the Universal Services Directive force ISPs to maintain a minimum quality of service and provide transparent information to customers about the services they provide. The Body of European Regulators of Electronic Communications, which is made up of representatives of telecoms regulators in the 27 EU countries, recently said that ISPs must provide consumers with accessible, understandable, meaningful, comparable and accurate information in order to allow them to make "informed choices" about services.
In a formal opinion (20-page / 193KB PDF) Hustinx explained that some of the practices employed by ISPs to manage traffic on their networks may be contrary to EU data protection and privacy laws. He said that ISPs may breach the laws when accessing users' personal data, such as account details, to determine how to manage their communications traffic.
"ISPs' increasing reliance on monitoring and inspection techniques impinges upon the neutrality of the Internet and the confidentiality of communications," Hustinx said. "This raises serious issues relating to the protection of users’ privacy and personal data."
Under the EU's Privacy and Electronic Communications Directive ISPs can process personal data "for the purpose of the transmission of a communication" subject to some conditions. The Directive states that providers are prohibited from "listening, tapping, storage or other kinds of interception or surveillance of communications" without consent from users concerned, other than when obliged to do, such as for national security purposes.
Under the Directive providers also must "take appropriate technical and organisational measures to safeguard security of its services".
Under the EU's Data Protection Directive organisations must ensure that they process personal data fairly and lawfully, and that it is collected for "specified, explicit and legitimate purposes" that are "adequate, relevant and not excessive in relation to the purposes". Organisations must also ensure that any personal information they keep is "kept in a form which permits identification of data subjects for no longer than is necessary for the purposes for which the data were collected or for which they are further processed," the Data Protection Directive states.
Hustinx said that regulatory guidance was needed and that it should determine "the inspection practices that are legitimate to ensure the smooth flow of traffic which may not require users' consent, such as, for example, the fight against spam," Hustinx said in a formal opinion.
"In addition to the intrusiveness of the monitoring applied, aspects such as, for example, the level of disturbance to the smooth flow of traffic that would otherwise occur, are relevant," he said.
The guidance should also explain to ISPs "which inspection techniques can be carried out for security purposes, which may not require users' consent" and explain "when monitoring requires individual's consent, notably the consent of all the users concerned, and the permissible technical parameters to ensure that the inspection technique does not entail processing of data that is not proportionate vis-à-vis its intended purposes," Hustinx said.
Further guidance "regarding the application of the necessary data protection safeguards" may also be needed, the EDPS said in his opinion.
Hustinx said that ISPs may need users' freely given, explicit, informed consent to conduct some inspection of their personal data when conducting some traffic management on their services, such as "to monitor and filter the communications of individuals for the purposes of limiting (or allowing) access to certain applications and services such as [file-sharing] and VoIP". This consent can only be considered to be given if users take "affirmative action" to give it, Hustinx said.
"Consent must be free, explicit and informed. It should be indicated through an affirmative action." Hustinx said in his opinion.
"These requirements put strong emphasis on the need to step up the efforts to ensure that individuals are properly informed, in a way that is direct, understandable and specific so that they can assess the effects of the practices and ultimately make an informed decision," he said. "Given the complexity of these techniques, giving meaningful prior information to users is one of the main challenges to obtain valid consent. Besides, there should be no detrimental consequences (including financial costs) towards users who do not consent to any monitoring."
ISPs must also consider whether it is proportionate to view personal information for the purposes of traffic management, Hustinx said.
"The proportionality principle plays a crucial role when ISPs engage in traffic management policies, whatever the legal ground for processing and the purpose: delivering the service, avoiding congestion or providing targeted subscriptions with or without access to certain services and applications," Hustinx said.
"This principle limits ISPs ability to engage in monitoring of the content of individual's communications that entail processing of excessive information or accruing benefits for ISPs only. What can logistically be performed by ISPs will depend on the level of intrusion of the techniques, the results required (for which they may accrue benefits) and the specific privacy and data protection safeguards applied. Prior to deploying inspection techniques, ISPs must engage in an assessment of whether these comply with the proportionality principle," he said.