Optimized routing for proxy use

A computing device for routing an email message to a recipient mailbox server over a network environment, comprising:

• a memory storing instructions;
• a processor coupled to the memory, the processor executing an email routing application, wherein the email routing application is configured to:
• transmit an email message to a proxy transport server;
• identify a store-and-forward (SAF) transport server associated with one or more recipient mailbox servers designated by the email message by applying one or more selection parameters for enabling the proxy transport server to select among a plurality of candidate SAF transport servers for routing the email message to, wherein:
• if any of the candidate SAF transport servers are located in a site where the proxy transport server is located, a local site selection parameter is applied;
• and
• if any of the candidate SAF transport servers are located in a remote site where the proxy transport server is not located, a remote site selection parameter is applied;
• transmit the email message from the proxy transport server to the identified SAF transport server;
• persist the email message at the SAF transport server before acknowledging the email message's receipt to the proxy transport server;
• transmit the email message to one or more recipients associated with the identified SAF transport server directly from the identified SAF transport server;
• identify another SAF transport server associated with one or more other recipient mailbox servers designated by the email message;
• and
• transmit the email message from the identified SAF transport server to the other identified SAF transport server for delivery to the one or more other recipients.

A computer-readable memory device with instructions stored thereon for routing an email message to a recipient mailbox server over a network environment, the instructions comprising:

• identifying a proxy transport server associated with a received email message using a domain name service (DNS);
• transmitting the email message to a proxy transport server;
• identifying one or more candidate store-and-forward (SAF) transport servers belonging to one or more server groups where one or more identified recipient mailbox servers are located by applying one or more selection parameters for enabling the proxy transport server to select one of the candidate SAF transport servers for routing the email message to, wherein applying one or more selection parameters further comprises:
• if any of the candidate SAF transport servers are located in a site where the proxy transport server is located, applying a local site selection parameter;
• and
• if any of the candidate SAF transport servers are located in a remote site where the proxy transport server is not located, applying a remote site selection parameter;
• categorizing the one or more candidate SAF transport servers into groups according to a site they belong to, wherein the site comprises one of:
• a local site and a remote site;
• ordering the one or more candidate SAF transport servers in the groups based on selecting a local site server first followed by remote site servers in an alternating order relative to remote sites associated with the remote site servers;
• transmitting the email message from the proxy transport server to one of the identified candidate SAF transport servers;
• transmitting the email message to one or more recipients associated with the SAF transport server receiving the email message;
• identifying another candidate SAF transport server associated with one or more other recipient mailbox servers designated by the email message;
• and
• transmitting the email message from the SAF transport server receiving the email message to the other identified candidate SAF transport server for delivery to the one or more other recipients.