i2p.www/www.i2p2/pages/ministreaming.html

{% extends "_layout.html" %}
{% block title %}ministreaming{% endblock %}
{% block content %}<p>The ministreaming library is a layer on top of the core 
<a href="i2cp">I2CP</a> that allows reliable, in order, and authenticated streams
of messages to operate across an unreliable, unordered, and unauthenticated 
message layer.  Just like the TCP to IP relationship, this streaming 
functionality has a whole series of tradeoffs and optimizations available, but
rather than embed that functionality into the base I2P code, it has been factored
off into its own library both to keep the TCP-esque complexities seperate and to
allow alternative optimized implemenations.</p>

<p>The current ministreaming library was written by mihi as a part of his 
<a href="i2ptunnel">I2PTunnel</a> application and then factored out and released
under the BSD license.  It is called the "mini"streaming library because it makes
some simplifications in the implementation, while a more robust streaming library
could be further optimized for operation over I2P.  The two main issues with 
the ministreaming library are its use of the traditional TCP two phase 
establishment protocol and the current fixed window size of 1.  The establishment
issue is minor for long lived streams, but for short ones, such as quick HTTP
requests, the impact can be <a href="minwww">significant</a>.  As for the window
size, the ministreaming library doesn't maintain any ID or ordering within the 
messages sent (or include any application level ACK or SACK), so it must wait 
on average twice the time it takes to send a message before sending another.</p>

<p>Even with those issues, the ministreaming library performs quite well in many
situations, and its <a href="http://www.i2p.net/javadoc/net/i2p/client/streaming/package-summary.html">API</a>
is both quite simple and capable of remaining unchanged as different streaming
implementations are introduced.  The library is deployed in its own 
ministreaming.jar, and it is located in CVS under 
<a href="http://dev.i2p.net/cgi-bin/cvsweb.cgi/i2p/apps/ministreaming/">
i2p/apps/ministreaming/</a>.  Developers in Java who would like to use it can
access the API directly, while developers in other languages can use it through
<a href="sam">SAM</a>'s streaming support.</p>{% endblock %}