System and method for an electronic mail attachment proxy

• US 8,260,861 B1
• Filed: 08/31/2005
• Issued: 09/04/2012
• Est. Priority Date: 08/31/2005
• Status: Active Grant

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property II LP (AT&T, Inc.)
• Inventors: Bruno, Aurelien, Grisi, Nicolas, Hericourt, Olivier, Le Pennec, Jean-Francois, Giroir, Didier
• Primary Examiner(s): Doan, Duyen
• Application Number:
  US11/218,063
• Time in Patent Office: 2,561 Days
• Field of Search: 709/206, 726/24
• US Class Current: 709/206
• CPC Class Codes: H04L 51/08 Annexed information, e.g. attachments

Abstract

Described is a system and method for receiving an electronic mail including an attachment file and separating the attachment file from the electronic mail. The attachment is then sent to a remote source and the attachment file is replaced with a substitute file including identifying data for retrieving the attachment file from the remote source. The electronic mail with the substitute file is then forwarded to a receiver.

Claims

1. A non-transitory computer readable storage medium storing a set of instructions executable by a processor, the set of instructions being operable to:

receive an electronic mail including an attachment file;

separate the attachment file from the electronic mail when a file size of the attachment file is greater than a predefined size threshold;

determine whether a remote file server has previously received a copy of the attachment file;

send the attachment file to the remote file server, if the remote file server has not previously received a copy of the attachment file, the remote file server being adapted to build a substitute file upon receiving the attachment file, the substitute file including a hash value computed from the attachment file, wherein, when the attachment file does not include prohibited content, the substitute file includes identifying data for retrieving one of the attachment file and the copy of the attachment file from the remote file server and wherein, when the attachment file includes prohibited content, the substitute file does not provide access to the attachment file and includes an indication of the prohibited content;

receive the substitute file from the remote file server;

replace the attachment file with the substitute file;

forward the electronic mail with the substitute file to the receiver;

receive a request from the receiver to obtain the attachment file, the request including the identifying data and the hash file; and

send the attachment file to the receiver in response to the request.

2. The non-transitory computer readable storage medium of claim 1, wherein the remote file server has a distribution list of users authorized to obtain the attachment file.

3. The non-transitory computer readable storage medium of claim 2, wherein the distribution list is provided by an electronic mail server to the remote file server during the substitute file creation.

4. The non-transitory computer readable storage medium of claim 1, wherein the receiver is a plurality of users.

5. A system, comprising:

a processor executing a set of instructions for operating an electronic mail server; and

a memory storing the set of instructions, the set of instructions comprising;

a receiving module to receive an electronic mail including an attachment file;

a separating module to separate the attachment file from the electronic mail when a file size of the attachment file is greater than a predefined size threshold;

a sending module to determine whether a remote file server has previously received a copy of the attachment file and send the attachment file to the remote file server, if the remote file server has not previously received a copy of the attachment file;

a replacement module disposed at the remote file server to build a substitute file and replace the attachment file with the substitute file, the substitute file including a hash value computed from the attachment file, wherein, when the attachment file does not include prohibited content, the substitute file includes identifying data for retrieving the attachment file from the remote file server and wherein, when the remote file server determines that the attachment file does include prohibited content, the substitute file does not provide access to the attachment file and includes an indication of the prohibited content;

a forwarding module to forward the electronic mail with the substitute file to the receiver; and

an attachment serving module receiving a request from the receiver to obtain the attachment file, the request including the identifying data and the hash file, and send the attachment file to the receiver in response to the request.

6. The system of claim 5, wherein the remote file server has a distribution list of users authorized to obtain the attachment file.

7. The system of claim 6, wherein the distribution list is provided by the electronic mail server to the remote source during the substitute file creation.

8. The system of claim 5, wherein the receiver is a plurality of users.

9. A system, comprising:

a network server including a processor and an electronic mail server, wherein the electronic mail server receives an electronic mail including an attachment file and separating the attachment file from the electronic mail when a file size of the attachment file is greater than a predefined size threshold; and

a remote file server receiving the attachment file from the electronic mail server, the remote file server further determining whether it has previously received a copy of the attachment file, the remote file server retaining the attachment file if it has not previously received a copy of the attachment file and discarding the attachment file if it has previously recovered a copy of the attachment file, the remote file server building a substitute file from the attachment file, the substitute file including a hash value computed from the attachment file, wherein, when the attachment file does not include prohibited content, the substitute file includes identifying data for retrieving one of the attachment file and the copy of the attachment file from the remote file server and wherein, when the remote file server determines that the attachment file does include prohibited content, the substitute file does not provide access to the attachment file and includes an indication of the prohibited content,

wherein the electronic mail server replaces the attachment file with the substitute file and forwards the electronic mail with the substitute file to the receiver, and

wherein the remote file server receives a request from the receiver to obtain the attachment file, the request including the identifying data and the hash file, and sends the attachment file to the receiver in response to the request.

10. The system of claim 9, wherein the electronic mail server is one of a receiving mail server and a transmitting mail server.

11. The system of claim 9, wherein the remote source further includes one of a virus checking utility, a file compare utility and a file compression utility.