Peer-to-Peer Technology for Faster Larger File Transfers

Early Internet and P2P Technology

The early Internet was predominantly a peer to peer system.  It was a network populated with academics and researchers, and computers connected to this network were largely equal in that each contributed as much information as they received. Transferring large files fast was not a consideration during this early stage of peer to peer connection. 
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As the Internet matured, the client - server model came to dominate, especially with the advent of http and the World Wide Web.  In this system, roles were separated with consumers as “clients” connecting to “servers” somewhere on the network that would distribute content and data.  Serving a massive audience required a vast number of these servers. It was during this time that large file transfer became an inherent issue for this model. 
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As demand grows in this model, performance declines and fragility increases.  The same number of servers must not only transfer large files faster but must meet the needs of a larger number of clients.  Sharing the growing load naturally degrades the performance available to each client.  Additionally, such systems are inherently fragile.  With a single source of content at the servers, you introduce single points of failure that can result in complete downtime for an application. 
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Thus, technologies like Content Delivery Networks (CDNs) emerged to aggregate and multiplex server capacity across many sources of content to help with fast large file sharing.  An unpredictable burst of demand could be more easily shared and building capacity closer to clients improves performance.  Such innovations made the early client - server model a little more robust, but at considerable cost to large filing sharing.
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Yet despite the inefficiency, the client server model remains predominant today.  Examples of the client - server model in common use include most web content, search engines, cloud computing applications and even common tools like FTP and rsync.

Peer to Peer is the Fastest Way to Transfer Files

Peer to Peer Large File Transfer in Action

Using a specific example, this section examines how peer to peer is always faster for large file transfers than any client-server architecture. To explain the technology in a simple way, we’ll make the following assumptions. The file we want to transfer with a P2P connection has five blocks. Each computer has a connection channel capable of sending one block per cycle.

We have a Sender that needs to send data to four devices A, B, C, and D (the Receivers).

• Stage 1 - Splitting the file:
  

  The Sender splits the file into independent pieces, and creates a meta-information data block that describes the pieces . In our example, the file consists of 5 pieces.We will mark each piece as colored dot: Red, Green, Yellow, Blue & Black.
  

  

• Stage 2 - Receiving the file:
  

  The Receivers request the file meta-information. When Receivers get the meta-information, they know the file in question contains five pieces, and at the moment only the Sender has them.
  

• Stage 3- Reading the file:

  Each cycle, the Receivers randomly select one piece from the file and start downloading it.  This continues until every Receiver has every piece of the file.