Abstract: A system is provided for enabling a source MTA to communicate with a target MTA via an SMTP proxy using SMTP commands for transmitting email messages in a networked environment. An email message may be received by a source mail transport agent (MTA) and the source MTA may route the incoming email message to a target MTA via an SMTP proxy. The SMTP proxy may serve as an intermediary proxy server for enabling the source MTA to communicate with an external and internal target MTA. The SMTP proxy may connect to a target MTA via a connection command, and the SMTP proxy may implement custom SMTP commands to communicate additional information about the source MTA to the target MTA. The system may additionally enable the SMTP proxy to perform actions designated by the SMTP commands and to communicate the result of the SMTP proxy's actions back to the source MTA.

Abstract: Architecture that enables data handling according to types of social relationships. A social graph is used to categorize the types of the social relationships of the tagged messaging users. The social graph can include social relationship categories for friends, family, coworkers, and blocked individuals of the recipient, for example. The social graph can also include metadata related to the tagged users. The metadata defines the social relationship of the tagged users to the recipient. Delivery of messages to the recipient from the tagged messaging users is managed based on the social graph. Delivery management can include blocking messages, allowing the messages through, or delivering the messages with high or low priority, for example. Email messages can be delivered to respective email locations based on the social graph. User information can be imported and/or mined from external sources to augment the social graph.

Abstract: A system is provided for enabling a source MTA to communicate with a target MTA via an SMTP proxy using SMTP commands for transmitting email messages in a networked environment. An email message may be received by a source mail transport agent (MTA) and the source MTA may route the incoming email message to a target MTA via an SMTP proxy. The SMTP proxy may serve as an intermediary proxy server for enabling the source MTA to communicate with an external and internal target MTA. The SMTP proxy may connect to a target MTA via a connection command, and the SMTP proxy may implement custom SMTP commands to communicate additional information about the source MTA to the target MTA. The system may additionally enable the SMTP proxy to perform actions designated by the SMTP commands and to communicate the result of the SMTP proxy's actions back to the source MTA.

Abstract: Architecture for enabling messages to be routed between network servers based on message requirements related to version, capabilities, and features, for example. The message requirements designate delivery over a transport path compatible with the message requirements. The message requirements can include a particular version or other features related to different software applications that require compatibility in message handling. Routing information is maintained related to a transport server or other network transport entity compatible with the message requirements and through which the message can be routed. The message is routed to the compatible transport server for delivery to the destination while avoiding delivery to transport servers incompatible with the message requirements.

Abstract: Architecture that enables data handling according to types of social relationships. A social graph is used to categorize the types of the social relationships of the tagged messaging users. The social graph can include social relationship categories for friends, family, coworkers, and blocked individuals of the recipient, for example. The social graph can also include metadata related to the tagged users. The metadata defines the social relationship of the tagged users to the recipient. Delivery of messages to the recipient from the tagged messaging users is managed based on the social graph. Delivery management can include blocking messages, allowing the messages through, or delivering the messages with high or low priority, for example. Email messages can be delivered to respective email locations based on the social graph. User information can be imported and/or mined from external sources to augment the social graph.