Abstract: A client device receives, from a user, a request to connect to a medium. The client device sends a request to a server to inquire whether a sufficient amount of credits is stored in an account for the user. The client device then receives a response to the inquiry. If the user account contains at least one credit, a connection is established between the client device and the medium. The server receives, from a controlling terminal, account information for the user, and a list of activities for reporting by the user. This information is stored in the user account. Credits are also stored in the user account. A report related to a performance of an activity part of the list of activities is received from the client device of the user. In response to receiving the report, the number of credits is incremented in the user account.

Abstract: An access node limits access of a user to a medium such as an Internet resource of a television program. The access node comprises upstream and downstream interfaces, a memory and a processor. The upstream interface is connectable to an Internet service provider. The downstream interface is connectable to a client device. The memory stores a user account for a user of the client device. The processor detects, via the downstream interface, an access from the user of the client device, in response to detecting the access, causes the client device to display a challenge, receives, via the downstream interface, a challenge response from the client device, and if the challenge response is a correct response, adds to the user account, a credit for connection of the client device to the medium. The access node may be part of a system including a server.

Abstract: An access node limits access of a user to a medium such as an Internet resource of a television program. The access node comprises upstream and downstream interfaces, a memory and a processor. The upstream interface is connectable to an Internet service provider. The downstream interface is connectable to a client device. The memory stores a user account for a user of the client device. The processor detects, via the downstream interface, an access from the user of the client device, in response to detecting the access, causes the client device to display a challenge, receives, via the downstream interface, a challenge response from the client device, and if the challenge response is a correct response, adds to the user account, a credit for connection of the client device to the medium. The access node may be part of a system including a server.