Abstract: Disclosed are systems and methods that facilitate securing communication channels used in a challenge-response system to mitigate spammer intrusion or deception. The systems and methods make use of unique IDs that can be added to outbound messages originating from a sender, a recipient, and a third-party server. The IDs can be correlated according to the relevant parties. Thus, for example, a sender can add a signed ID to an outgoing message. A challenge sent back to the sender for that particular message can echo the same ID or a new ID derived from the original ID to allow a sender to verify that the challenge corresponds to an actual message. The IDs can include cookies as well to facilitate correlation of messages and to facilitate the retrieval of messages once a sender is determined to be legitimate.

Abstract: The present invention provides a unique system and method that facilitates incrementally updating spam filters in near real time or real time. Incremental updates can be generated in part by difference learning. Difference learning involves training a new spam filter based on new data and then looking for the differences between the new spam filter and the existing spam filter. Differences can be determined at least in part by comparing the absolute values of parameter changes (weight changes of a feature between the two filters). Other factors such as frequency of parameters can be employed as well. In addition, available updates with respect to particular features or messages can be looked up using one or more lookup tables or databases. When incremental and/or feature-specific updates are available, they can be downloaded such as by a client for example. Incremental updates can be automatically provided or can be provided by request according to client or server preferences.

Abstract: Screened participant classes are established that enable a communication participant notification continuum which may be utilized to facilitate appropriate notification of a particular computer facilitated communication participant's legal status and/or subject matter sensitivities to computer facilitated communication service providers and/or other communication participants. For example, a level of participant class screening may be adjusted depending on a level of trust and/or communication history with a particular communication participant. Screened participant classes may be associated with particular communication devices and/or communication device users. Once notified with a set of screened participant classes, the notified communication participant may adjust subject matter that is communicated to the notifying communication participant based on the set of screened participant classes.