Abstract: A video on demand system includes a head-end coupled through a proxy server to plural client terminals. The proxy server performs (or cooperates with another component in performing) various functions, including user interface definition, security, system administration (e.g. channel management, load distribution, and failover), and protocol translation.

Abstract: A video on demand system includes a head-end coupled through a proxy server to plural client terminals. The proxy server performs (or cooperates with another component in performing) various functions, including user interface definition, security, system administration (e.g. channel management, load distribution, and failover), and protocol translation.

Abstract: Systems and methods for controlling the ability of scripts to access objects defined at the client. The client stores an access control data structure having multiple entries. Each entry is associated with one or more objects for which access is to be controlled. The entries include a source identifier field containing one or more URLs and a permission identifier field containing data defining a permission. When the client receives a script from a script source, such as a web site, the client begins execution of the script until the script requests access to an object. The client identifies a relevant entry of the access control data structure, which is an entry that is associated with the requested object and lists the URL of the script source in the source identifier field. The client applies the permission defined by the permission identifier of the relevant entry to the request, thereby granting or denying access to the script.

Abstract: Systems and methods for controlling the ability of scripts to access objects defined at the client. The client stores an access control data structure having multiple entries. Each entry is associated with one or more objects for which access is to be controlled. The entries include a source identifier field containing one or more URLs and a permission identifier field containing data defining a permission. When the client receives a script from a script source, such as a web site, the client begins execution of the script until the script requests access to an object. The client identifies a relevant entry of the access control data structure, which is an entry that is associated with the requested object and lists the URL of the script source in the source identifier field. The client applies the permission defined by the permission identifier of the relevant entry to the request, thereby granting or denying access to the script.

Abstract: Systems and methods for controlling the ability of scripts to access objects defined at the client. The client stores an access control data structure having multiple entries. Each entry is associated with one or more objects for which access is to be controlled. The entries include a source identifier field containing one or more URLs and a permission identifier field containing data defining a permission. When the client receives a script from a script source, such as a web site, the client begins execution of the script until the script requests access to an object. The client identifies a relevant entry of the access control data structure, which is an entry that is associated with the requested object and lists the URL of the script source in the source identifier field. The client applies the permission defined by the permission identifier of the relevant entry to the request, thereby granting or denying access to the script.

Abstract: Methods for using a conditional access system to modify access control information maintained at a set-top box or another client system. The access control information regulates the availability of information or entertainment services at the client or controls the ability of scripts executed at the client to access objects defined at the client. The conditional access system can be a conventional conditional access, such as those used by cable television providers, that has been adapted to modify the access control information. The access control information includes multiple entries, each being referenced by a token identifier. The conditional access system transmits a command and an accompanying token to the client to instruct the client how to modify the access control information. The entry that is to be modified is identified by comparing the token with the token identifiers.