Protocols » History » Revision 22
Revision 21 (Greg Burri, 05/26/2012 12:48 AM) → Revision 22/26 (Greg Burri, 05/26/2012 01:01 AM)
h1. Protocols
* [[Protocol core-core]]
* [[Protocol core-GUI]]
There is two main protocols, one between cores and one between GUI and core. Both are using "protocol buffers":http://code.google.com/p/protobuf/ for describing the exchanged messages.
Each data sent over the network (using TCP or UDP) are formatted like this :
<pre>
<messageType:uint32><size:uint32><senderId:20*uint8><serializedMessage>
</pre>
Where :
* _messageType_ is a number which determine the message type, more information in the proto files.
* _size_ is the size of the following serialized message. It may be zero for an empty message.
* _senderId_ is the sender id.
* _serializedMessage_ is the data serialized by protocol buffer.
The first three items is the header and is exactly 28 bytes long.
h2. Links to resource (DRAFT)
h3. Proposal 1
Links can be shared across peers. It locates a remote resource like folder or file from a specific peer. It can contain chunk hashes, thus the source peer doesn't need to be online to download a file or a folder.
_dl://[<peer name>][:<file id>][:<shared id>/<folder>/<file>]_
* <peer name> : Not required and not used to locate the resource, just an information for the user.
* <file id> : its the n first group of nibble of the m first chunk where _n * m = 40 nibbles_ (20 octets).
** 20,87cace382f7371cd3fab3cb0a53b93b7cd9719f6 : 20 chunks of 2 nibbles.
** 8,05649bcbf065e0d032ada540d4a749d98db055cf : 8 chunks of 5 nibbles.
* <shared id> : Contains only the beginning of the hash.
h4. Examples
* _dl://20,87cace382f7371cd3fab3cb0a53b93b7cd9719f6_
* _dl://pierre:20,87cace382f7371cd3fab3cb0a53b93b7cd9719f6_
* _dl://pierre:20,87cace382f7371cd3fab3cb0a53b93b7cd9719f6:dac4f75c/my%20movies/LOLCat.avi_
* _dl://pierre:dac4f75c/my%20movies/LOLCat.avi_
* _dl://pierre:dac4f75c/my%20movies_
h3. Proposal 2
This version is much simpler, it doesn't identify the file and contains only the path to the ressource.
_dl://<peer name>(<peer ID>)<path>_
_<path>_ always starts with a slash. It can be a folder or a file.
h4. Examples
* _dl://pierre(d51f479)/my%20movies/LOLCat.avi_
h3. Proposal 3
Folders: _dl://[<peer name>]:[<peer id>]:(<shared id>|<shared name>)[/<path>]_
Files: _dl://<file id>:<file name>
<file id> is a hash built from all the chunk hashes. A new field must be added to the IMAlive message to ask if someone know a particular file ID, is someone know the file ID then he replies with a ChunksOwned message (rename the message?) with a field named file_state.
h4. Examples
* _dl://Pierre::a%20shared%20folder/my%20movies/_
* _dl://Pierre:7c0215d7f758bce8d00ffc467be7d5f5f7c9f929:a%20shared%20folder/my%20movies/_
* _dl://Pierre:7c0215d7f758bce8d00ffc467be7d5f5f7c9f929:68181cd1c7495122493b74170f76700ac30c81d1/my%20movies/_
* _dl://ea627f2d65c12a78aa5c0c154ba7e187d3fefe80:my%20movies/LOLCat.avi