Abstract: Techniques are described for use with social networks and associated access information, such as access control lists, indicating which users are allowed to access the social networks. The social networks represent relationships between users. The social networks and access control lists may be represented in a graph which is traversed in connection with performing different operations using the social networks.

Abstract: Techniques are described for use with social networks and associated access information, such as access control lists, indicating which users are allowed to access the social networks. The social networks represent relationships between users. The social networks and access control lists may be represented in a graph which is traversed in connection with performing different operations using the social networks.

Abstract: A technique for interconnecting users of different instant messaging services without requiring the users to change their account identifiers. A first user of a primary messaging service can communicate with a second user of a second, federated messaging service, where the first user is associated with a non-managed domain of the primary messaging service. When the first user sends a message to the second user, the primary messaging service decorates or modifies the first user's identifier as the sender so that the message, when received, appears to have come from a managed domain of the primary messaging service rather than from the non-managed domain. When a message from the second user is sent to the first user, the first user's identifier is undecorated in a reverse operation.