> password-protecting the internet connection, provided that those users are required to reveal their identity in order to obtain the required password and may not therefore act anonymously
The whole question by the way was not settled by the court but referred back to lower instances and is not something that will have to be answered uniformly across the EU. The court merely found that such a law would be allowed under EU rules.
If the requirement is just to have the user reveal their personal identity before using the network, and nothing is said about keeping that info afterwards, then something like this would be possible: ask the user for their personal info, handle them a hash that would work as a password to reconnect to the network within a short time window, and past this time forget said hash and the user info.
Could this work? (IANAL.)