Under a monopolistic or concessionary regime there remains the problem of preventing access of players to unauthorized gambling sites.

The Italian solution requires the AAMS to provide Italian ISPs with a blacklist of names of sites to block (associating the names in the server of the DNS of the ISP to an IP of the AAMS). This solution, however, is ineffective because it is can be bypassed in a legal fashion by any user by changing one’s DNS (by using, for example OpenDNS).

A more effective solution is to act at the IP level using techniques similar to those of the firewalls (always with the cooperation of the ISP), but the problems of the international legality of such actions of this type are potentially manifold and in any case, gambling sites can circumvent the problem via a continuous changes in IP.

In the U.S. (where there is no possibility of obtaining licences or permits for on-line gambling) it is prohibited for banks to make payments (and receive winnings) with on-line gambling sites, but even this method seems to be surmountable.

This situation of a lack of effective controls is the main problem of monopoly or concession schemes governing on-line gambling.