Access limited EMM distribution lists

• US 8,166,113 B2
• Filed: 08/02/2006
• Issued: 04/24/2012
• Est. Priority Date: 08/02/2006
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Costea, Mihai, Ryvkin, Konstantin, Pearson, Malcolm E., Williams, Roy
• Primary Examiner(s): Backer, Firmin
• Assistant Examiner(s): Emdadi, Keyvan
• Application Number:
  US11/461,984
• Publication Number:
  US 20080034042A1
• Time in Patent Office: 2,092 Days
• Field of Search: 709/206, 709/220, 709/225, 709/237, 709/245
• US Class Current: 709/206
• CPC Class Codes: H04L 51/212 using filtering or selective blocking

Abstract

An electronic mail message (EMM) addressed to a distribution list of an enterprise is received at a server of the enterprise from a sending address outside of the enterprise. If the distribution list has no external addresses, then the EMM is blocked from being delivered to the distribution list. In an embodiment, if the distribution list has an external address and the sending address is identified in a safe sender list corresponding to the distribution list, then the EMM is delivered to the distribution list. In an embodiment, if the distribution list has an external address, the sending address is not in a safe sender list corresponding to the distribution list, and the content of the message is approved, then the EMM is delivered to the distribution list.

Claims

1. A method of processing electronic mail messages addressed to a particular distribution list of an enterprise from a sending address external to the enterprise wherein the particular distribution list is one of a plurality of distribution lists associated with the enterprise, said particular distribution list comprising a list of electronic mail message addresses, said plurality of distribution lists including internal distribution lists having only internal addresses and external distribution lists having internal and external addresses, said method comprising:

storing a plurality of safe sender lists, each stored safe sender list corresponding to one and only one of the external distribution lists of the enterprise and each external distribution list corresponding to one and only one of the stored plurality of safe sender lists, wherein for each particular external distribution list, its corresponding safe sender list identifies particular external addresses which are authorized to send electronic mail messages to the particular external distribution list;

receiving at a server of the enterprise an electronic mail message addressed to one of the particular distribution lists, said received electronic mail message sent from a specific external sending address;

first determining whether the particular distribution list addressed by the received electronic mail message is an internal distribution list or an external distribution list;

in response to first determining, if the particular distribution list is an external distribution list, then second determining whether the specific external sending address is one of the particular external addresses of the safe sender list corresponding to the particular distribution list; and

selectively forwarding the received electronic mail message to the addresses of the one of the particular distribution lists as a function of the first determining whether the particular distribution list is internal or external and as a function of the second determining whether the specific external sending address is on the safe sender list of the particular distribution list, wherein said selectively forwarding further comprises;

blocking the received electronic mail message from being delivered to the addresses of the particular distribution list if the first determining determines that the particular distribution list is an internal distribution list;

delivering the received electronic mail message to the addresses of the particular distribution list if the first determining determines that particular distribution list is an external distribution list and if the second determining determines that the specific external sending address is identified in the safe sender list corresponding to the particular distribution list;

hiding the addresses of members of the particular distribution list and the corresponding safe sender list as a function of the delivering, by preventing disclosure of addresses of the members of the particular distribution list and the corresponding safe sender list, said hiding comprising displaying a nickname for the members of the particular distribution list and the corresponding safe sender list instead of the addresses of the members; and

blocking the received electronic mail message to the addresses of the particular distribution list if the first determining determines that particular distribution list is an external distribution list and if the second determining determines that the specific external sending address is not identified in the safe sender list corresponding to the particular distribution list further comprising;

adding or removing a particular address from the particular distribution list by and responsive to said adding or removing, and without any further input, adding or removing the particular address from the safe sender list corresponding to the particular distribution list.

2. The method of claim 1 further comprising content filtering the received electronic mail message if the particular distribution list is an external distribution list and the sending address is not identified in the safe sender list corresponding to the particular distribution list.

3. The method of claim 1 wherein said blocking comprises at least one of the following:

providing no status message or notice to an external server associated with the sending address;

generating a status message at the server of the enterprise and providing said status message to said sending address;

generating a notice at the server of the enterprise, providing said notice to a server associated with the sending address, generating a status message at the server associated with the sending address in response to the received notice, and providing said status message to said sending address; and

notifying an administrator associated with the enterprise of the blocked electronic mail message.

4. The method of claim 1 further comprising authenticating the sending address and blocking the electronic mail message from being delivered to the particular distribution list if the sending address is not authenticated.

5. The method of claim 1 wherein the particular distribution list is created by a user other than an administrator at a user computer and subsequently copied to the server.

6. A system for processing an electronic mail message received by an enterprise addressed to a particular distribution list of the enterprise from a sending address external to the enterprise wherein the particular distribution list is one of a plurality of distribution lists of the enterprise, said particular distribution list comprising a list of electronic mail message addresses, said plurality of distribution lists including internal distribution lists having only internal addresses and external distribution lists having internal and external addresses, said system comprising:

a server of the enterprise for receiving the electronic mail message addressed to the particular distribution list, said received electronic mail message sent from a specific sending address external to the enterprise;

a plurality of safe sender lists stored on the server, each stored safe sender list corresponding to one and only one of the external distribution lists of the enterprise, wherein each external distribution list corresponding to one and only one of the stored plurality of safe sender lists, wherein for each external distribution list, its corresponding safe sender list identifies external addresses which are authorized to send electronic mail messages to the corresponding external distribution list; and

wherein the server executes instructions for;

first determining whether the particular distribution list addressed by the received electronic mail message is an internal distribution list or an external distribution list;

in response to first determining, if the particular distribution list is an external distribution list, then second determining whether the specific external sending address is one of the particular external addresses of the safe sender list corresponding to the particular distribution list; and

selectively forwarding the received electronic mail message to the addresses of the particular distribution list as a function of the first determining whether the particular distribution list is internal or external and as a function of the second determining whether the specific external sending address is on the safe sender list corresponding to the particular distribution list, wherein said selectively forwarding further comprises;

blocking the received electronic mail message from being delivered to the addresses of the particular distribution list if the first determining determines that the particular distribution list is an internal distribution list;

delivering the received electronic mail message to the addresses of the particular distribution list if the first determining determines that the particular distribution list is an external distribution list and if the second determining determines that the sending address is identified in the safe sender list corresponding to the particular distribution list;

in response to the delivering, hiding the addresses of members of the particular distribution list and the corresponding safe sender list by preventing disclosure of addresses of the members of the particular distribution list and the corresponding safe sender list, said hiding comprising displaying a nickname for the members of the particular distribution list and the corresponding safe sender list instead of the addresses of the members; and

blocking the received electronic mail message from the addresses of the particular distribution list if the first determining determines that the particular distribution list is an external distribution list and the second determining determines that the specific external sending address is not identified in the safe sender list corresponding to the particular distribution list further comprising;

adding or removing a particular address from the particular distribution list by and responsive to said adding or removing, and without any further input, adding or removing the particular address from the safe sender list corresponding to the particular distribution list.

7. The system of claim 6 wherein the server further content filters the received electronic mail message if the particular distribution list is an external distribution list and the sending address is not identified in the safe sender list corresponding to the particular distribution list.

8. The system of claim 6 wherein if the server blocks the electronic mail message from the particular distribution list, then at least one of the following:

the server of the enterprise does not return a status message or notice to an external server associated with the sending address;

the server of the enterprise generates a status message and provides said status message to said sending address;

the server of the enterprise generates a notice, provides said notice to a server associated with the sending address, the server associated with the sending address generates a status message in response to the received notice, and the server associated with the sending address provides said status message to said sending address; and

the server of the enterprise notifies an administrator associated with the enterprise of the blocked electronic mail message.

9. The system of claim 6 wherein the server authenticates the sending address and blocks the electronic mail message from being delivered to the particular distribution list if the sending address is not authenticated.

10. The system of claim 6 wherein the particular distribution list is created by a user other than an administrator at a user computer and subsequently copied to the server.

11. The system of claim 6 wherein:

addresses are added to or removed from the particular distribution list by a user other than an administrator; and

addresses are added to or removed from the safe sender list corresponding to the particular distribution list by a user other than an administrator.

12. A method of creating or maintaining a plurality of safe sender lists, each safe sender list corresponding to one and only one external distribution list of a plurality of external distribution lists of an enterprise and each external distribution list corresponding to one and only one safe sender list, each of said external distribution lists comprising a list of electronic mail message addresses including addresses internal to the enterprise and addresses external to the enterprise, wherein each safe sender list identifies addresses external to the enterprise which are authorized to send electronic mail messages to the external distribution list corresponding to the safe sender list, said method comprising:

receiving an electronic mail message addressed to a particular distribution list of the enterprise, said received electronic mail message sent from a specific sending address external to the enterprise, said electronic mail message including a plurality of addresses in addition the particular external distribution list;

first determining whether the particular distribution list addressed by the received electronic mail message is an internal distribution list or an external distribution list;

in response to first determining, if the particular distribution list is an external distribution list, then second determining whether the specific external sending address is one of the particular external addresses of the safe sender list corresponding to the particular distribution list;

blocking the received electronic mail message from being delivered to the addresses of the particular distribution list if the first determining determines that the particular distribution list is an internal distribution list;

delivering the received electronic mail message to the particular distribution list if the first determining determines that the particular distribution list is an external distribution list and if the second determining determines that the sending address is identified in the safe sender list corresponding to the particular distribution list, wherein said delivering comprises at least one of the following;

comparing the plurality of addresses of the received electronic mail message to at least one of a global authoritative address list of the enterprise and a domain list of the enterprise to identify addresses of the received plurality of addresses which are external to the enterprise, and hiding only the addresses of members of the particular distribution list and the corresponding safe sender list to prevent disclosing addresses of the members, said hiding comprising displaying a nickname for the distribution list instead of the addresses of the members; and

copying the identified external addresses to the safe sender list corresponding to the particular distribution list; and

blocking the received electronic mail message from the particular distribution list if the first determining determines that the particular distribution list is an external distribution list and the second determining determines that the specific external sending address is not identified in the safe sender list corresponding to the particular distribution list.

13. The method of claim 12 further comprising adding or removing an address from the safe sender list in response to the received electronic mail message.

14. The method of claim 13 further comprising further comprising determining whether the received electronic mail message is from a user who created the received distribution list and adding or removing an address from the safe sender list only if the sender of the received electronic mail message is determined to be the user who created the received distribution list.