History database structure for Usenet

A method for operating a history database for a server, comprising the steps of:

• (a) receiving a unique identifier at the server;
• (b) hashing said unique identifier into at least a first hash value and a second hash value;
• (c) mapping said first hash value into a storage location within a value database, wherein said storage location contains at least a record pointer to a linked list of records, said records comprised of at least the following:
• (i) a first hash field;
• (ii) a second hash field;
• (iii) a payload field;
• and
• (iv) a linking pointer;
• and
• (d) searching said linked list of records for a match of said second hash value.

A system for communicating Usenet articles, comprising:

• code for receiving an offer to download a Usenet article, wherein said offer comprises a unique identifier of said Usenet article;
• code for hashing said unique identifier to a hash memory identifier of a memory location that stores a pointer to a first record of a linked list that maintains a history of selected previously downloaded Usenet articles;
• code for searching a lock table to determine whether a previous offer to download said Usenet article is being processed;
• and
• code for searching said linked list utilizing said pointer to determine whether said Usenet article has been download, wherein said code for searching said linked list is operable only when said code for searching said lock table determines that a previous offer to download said Usenet article is not being processed.