What is yenc?
yEnc is a new encoding protocol that uses 8-bit encoding to reduce the amount of data being sent and received. The traditional UUencode and base64 encodings incur a 30% overhead by converting all binary data into “safe” characters that can be transported over Usenet. At its inception, Usenet had a variety of problems with 8-bit data, resulting from the fact that a large number of disparate subnets had been combined into the “internet”. Some of these subnets could only pass 7-bit data. Some of them used different (non-ASCII) character sets, which sometimes resulted in translation problems. Some of them treated certain characters or sequences as “special”. These days, in TCP/IP, the vast majority of our servers can handle 8-bit data, to a large degree. There are still some “forbidden” cases that can cause odd behaviour. yEnc has made a “good compromise” that allows all but a handful of characters to be represented by an 8-bit value. This handful is encoded by prefixing its value with an
