Usenet NZB

Historia

Usenet is a worldwide distributed discussion system available on computers. It was developed from the general-purpose Unix-to-Unix Copy (UUCP) dial-up network architecture. Tom Truscott and Jim Ellis conceived the idea in 1979, and it was established in 1980. Users read and post messages (called articles or posts, and collectively termed news) to one or more categories, known as newsgroups. Usenet resembles a bulletin board system (BBS) in many respects and is the precursor to Internet forums that are widely used today. Discussions are threaded, as with web forums and BBSs, though posts are stored on the server sequentially. The name comes from the term users network. A major difference between a BBS or web forum and Usenet is the absence of a central server and dedicated administrator. Usenet is distributed among a large, constantly changing conglomeration of servers that store and forward messages to one another via news feeds. Individual users may read messages from and post messages to a local server, which may be operated by anyone. Usenet is significantly different from modern P2P services; most P2P users distributing content are typically immediately identifiable to all other users by their network address, but the origin information for a Usenet posting can be completely obscured and unobtainable once it has propagated past the original server. NZB is an XML-based file format for retrieving posts from NNTP (Usenet) servers. The format was conceived by the developers of the Newzbin.com Usenet Index. NZB is effective when used with search-capable websites. These websites create NZB files out of what is needed to be downloaded. Using this concept, headers would not be downloaded hence the NZB method is quicker and more bandwidth-efficient than traditional methods. Each Usenet message has a unique identifier called the Message-ID. When a large file is posted to a Usenet newsgroup, it is usually divided into multiple messages (called segments or parts) each having its own Message-ID. An NZB-capable Usenet client will read all needed Message-IDs from the NZB file, download them and decode the messages back into a binary file (usually using yEnc or Uuencode)