What is yenc?
Yencoding is a slightly more efficient way to post binary files. This encoding is very popular in some newsgroups because it allows smaller posts and quicker downloads. Some newsreaders come ready to Ydecode postings, but some (e.g.: Outlook Express) require a second step to decode the attached file. For more information (and free download of the Yenc encoder/decoder) visit www.yenc.org. A web search on for Yenc will give over 25,000 links, so there is a lot of information available about this subject.
If you encountered yEnc messages on the newsgroups you may have been disappointed because Outlook Express has no yEnc decoder. This article explains how to decode yEnc in Outlook Express and why is it so popular. yEnc is relatively new encoding method (announced in 2001) used for encoding binary files on the Usenet (also called newsgroups) into a format the Usenet server is capable of sending and receiving. Originally, the newsgroups were not designed to handle binary data at all. First news readers could only handle textual posts. As the time passed the Usenet evolved and more and more binary posts (such as pictures, programs, music and videos) began to appear in the newsgroups. People posted them in so called binaries groups. The problem with servers that could only accept textual content has been partially solved by creating encoding methods that could convert any 8-bit binary file into a 6-bit or 7-bit text encoded file that could fit into printable range of the ASCII character set
yEnc is simply another form of encoding for binary files on UseNet or email. It is inherently much more efficient than the older methods such as UUE, MIME, BinHex, or Quoted Printable- saving approximately 40% of the bandwidth required to transmit and receive the files, and also needing 40% less storage space on UseNet servers! It also offers better error detection than the older methods. Read this for some
(Page 2 of 5 ) News and Mail transfer require that a binary attachment is “encoded” before it is sent. And they are “decoded” after they have been received. Normally all this is done by your newsreader (or mail-program). You dont see it. Most dont even know it. The encoding is necessary because the special methods for the transfer of news & mail protocols require it. A message with a binary which is not encoded is corrupted during transmission – or transmission is denied at all. Transport of messages by News and Mail was restricted to US-ASCII characters when the protocols were written (20 years ago). These services have been created to transport only plain US-text. Special characters (control-characters, symbols, non-US-characters) were forbidden – and used for special purposes. But because people wanted to send also binary attachments by News and Mail some ‘tricks’ were implemented: The binary was changed to “allowed US-ASCII-characters” before transmission (encoding) – and back to a
