LOOPC软件工作室

Web File Distribution Protocol (WFDP v 1.0)

Team:        LOOPC Software Studio
Copyright:    http://www.loopc.com

Version:        1.0

Create Date:        2009/09/24
Last Update:        2009/09/27

What is WFDP?

WFDP (Web File Distribution Protocol) is a file distribution protocol that uploads or downloads large files through many different URLs of websites. The core technology principle is that the publisher splits the specified large file into many sub-files, and then publishes all the sub-files to any URLs address, in the meantime; the publisher needs generate the suffix “wfdp” file which contains basic description of the large file and the URL of each sub-file, offset of each sub-file, size of each sub-file and so on. You can download and get all the sub-files and merge them to the original large file from Internet if the receiver software or the third software supports this WFDP protocol.   


The functions of WFDP

Faster Distribution
The traditional upload and download for web file is working in one server, in this case, the server will consume huge system resources and the speed obviously becomes very slow in this time if many people upload or download the same file together at the same time. However, If we are Using WFDP, the sub-files can be distributed to different servers and make them provide the uploading and downloading services at one time, so that reducing the pressure on each server, achieving load balancing, and greatly increased the speed of uploading and downloading。

Free Share
The purpose of Internet is that interconnect networks and share information, actually the vast Internet own huge free space, but the large part of which is not used enough. As ordinary Internet users, generally they have not their own servers, and there is always a variety of restrictions on the free space, so if you want collection, sharing large files there is no good alternative program. However, the WFDP sub-files can be packaged into any existing files, such as images, sounds, video, etc. and the sub-file size is very small, so that if using the WFDP, it can take full advantage a lot of idle resources of the Internet and makes everyone freely access or share large files each other at high speed.

WFDP Definition of Structure

1 WFDP file usually uses “Wfdp” as the file name suffix, the content is based on UTF-8 encoded XML strings used to record the file name, file size, Hash value of file, last modification date, publisher and the sub-file offset, sub-file size, Hash value of sub-file, sub-file URL, and this “wfdp” file can be used as an ordinary text editor to view and edit.

summary：
NetFile
FileName                        //the original file name
FileSize                        // the original file size
  HashCode                        //the MD5 of the original file
  LastModifyTime                  //the last update date of the original file
  Description?                    //the description information of the original file, can be null
  Publisher?                      //the publisher of the original file，can be null
  SubFiles
      SubFile+
        Offset                    //the offset value of the sub-file from the original file
        Size                      //the size of the sub-file
        HashCode                  //the MD5 of the sub-file
        URL                      //the URL of the sub-file

syntax：
<!ELEMENT NetFile (FileName,FileSize,HashCode,LastModifyTime,Description?,Publisher?,SubFiles)> 
<!ELEMENT SubFiles (SubFile+)>
<!ELEMENT SubFile (Offset,Size,HashCode,URL)>

example：
<?xml version="1.0"?>
<NetFile xmlns : xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns : xsd="http://www.w3.org/2001/XMLSchema">
  <FileName> wfdp demo.rmvb</FileName>
  <FileSize>1073741824</FileSize>
  <HashCode>e96ace772f9649d78ab8322edeec4ac2</HashCode>
<LastModifyTime>2009-09-22T15:26:58.578125+08:00</LastModifyTime>
<Description> WFDP (Web File Distribution Protocol) is a file distribution protocol that uploads or downloads large files through many different URLs of websites...</Description>
  <Publisher>HeDaode</Publisher>
  <SubFiles>
    <SubFile>
      <Offset>0</Offset>
      <Size>1048576</Size>
      <HashCode>16ea9da7bfba4f0eb302b4b62b53dec9</HashCode>
      <URL>http://loopc.com/netfiles/ wfdp demo /0.part</URL>
    </SubFile>
    <SubFile>
      <Offset>1048576</Offset>
      <Size>1048576</Size>
      <HashCode>782e35905ea144118163baacbb1200b3</HashCode>
      <URL>http://famingkuang.com/netfiles/ wfdp demo /1.part</URL>
</SubFile>       
………..
    <SubFile>
      <Offset>1072693248</Offset>
      <Size>1048576</Size>
      <HashCode>9346810ff88344a4bd7a4309d40524f5</HashCode>
      <URL>http://famingkuang.cn/netfiles/ wfdp demo /1023.part</URL>
    </SubFile>
  </SubFiles>
</NetFile>