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10bd32030SDmitri TikhonovLSQUIC Documentation
20bd32030SDmitri Tikhonov====================
30bd32030SDmitri Tikhonov
40bd32030SDmitri TikhonovThis is the documentation for LSQUIC_ |release|, last updated |today|.
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60bd32030SDmitri TikhonovLiteSpeed QUIC (LSQUIC) Library is an open-source implementation of QUIC
70bd32030SDmitri Tikhonovand HTTP/3 functionality for servers and clients.  LSQUIC is:
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90bd32030SDmitri Tikhonov- fast;
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110bd32030SDmitri Tikhonov- flexible; and
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130bd32030SDmitri Tikhonov- production-ready.
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150bd32030SDmitri TikhonovMost of the code in this distribution has been  used in our own products
160bd32030SDmitri Tikhonov-- `LiteSpeed Web Server`_, `LiteSpeed Web ADC`_, and OpenLiteSpeed_ --
170bd32030SDmitri Tikhonovsince 2017.
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1936fcb9aaSDmitri TikhonovCurrently supported QUIC versions are Q043, Q046, Q050, ID-27, ID-28,
20b62ec17fSDmitri TikhonovID-29, ID-30, and ID-31.
210bd32030SDmitri TikhonovSupport for newer versions will be added soon after they are released.
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230bd32030SDmitri TikhonovLSQUIC is licensed under the `MIT License`_; see LICENSE in the source
240bd32030SDmitri Tikhonovdistribution for details.
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2636fcb9aaSDmitri TikhonovFeatures
2736fcb9aaSDmitri Tikhonov--------
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2936fcb9aaSDmitri TikhonovLSQUIC supports nearly all QUIC and HTTP/3 features, including
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3136fcb9aaSDmitri Tikhonov- DPLPMTUD
3236fcb9aaSDmitri Tikhonov- ECN
3336fcb9aaSDmitri Tikhonov- Spin bits (allowing network observer to calculate a connection's RTT)
3436fcb9aaSDmitri Tikhonov- Path migration
3536fcb9aaSDmitri Tikhonov- NAT rebinding
3636fcb9aaSDmitri Tikhonov- Push promises
3736fcb9aaSDmitri Tikhonov- TLS Key updates
3836fcb9aaSDmitri Tikhonov- Extensions:
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40b1a7c3f9SDmitri Tikhonov - :ref:`apiref-datagrams`
4136fcb9aaSDmitri Tikhonov - Loss bits extension (allowing network observer to locate source of packet loss)
4236fcb9aaSDmitri Tikhonov - Timestamps extension (allowing for one-way delay calculation, improving performance of some congestion controllers)
4336fcb9aaSDmitri Tikhonov - Delayed ACKs (this reduces number of ACK frames sent and processed, improving throughput)
4436fcb9aaSDmitri Tikhonov - QUIC grease bit to reduce ossification opportunities
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4636fcb9aaSDmitri TikhonovArchitecture
4736fcb9aaSDmitri Tikhonov------------
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4936fcb9aaSDmitri TikhonovThe LSQUIC library does not use sockets to receive and send packets; that is handled by the user-supplied callbacks.  The library also does not mandate the use of any particular event loop.  Instead, it has functions to help the user schedule events.  (Thus, using an event loop is not even strictly necessary.)  The various callbacks and settings are supplied to the engine constructor.
5036fcb9aaSDmitri TikhonovLSQUIC keeps QUIC connections in several data structures in order to process them efficiently.  Connections that need processing are kept in two priority queues: one holds connections that are ready to be processed (or "ticked") and the other orders connections by their next timer value.  As a result, no connection is processed needlessly.
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520bd32030SDmitri Tikhonov.. _LSQUIC: https://github.com/litespeedtech/lsquic
530bd32030SDmitri Tikhonov.. _`MIT License`: http://www.opensource.org/licenses/mit-license.php
540bd32030SDmitri Tikhonov.. _`LiteSpeed Web Server`: https://www.litespeedtech.com/products/litespeed-web-server/
550bd32030SDmitri Tikhonov.. _`LiteSpeed Web ADC`: https://www.litespeedtech.com/products/litespeed-web-adc/
560bd32030SDmitri Tikhonov.. _OpenLiteSpeed: https://openlitespeed.org/
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580bd32030SDmitri TikhonovContents
590bd32030SDmitri Tikhonov--------
600bd32030SDmitri Tikhonov
610bd32030SDmitri Tikhonov.. toctree::
620bd32030SDmitri Tikhonov   :maxdepth: 2
630bd32030SDmitri Tikhonov
640bd32030SDmitri Tikhonov   gettingstarted
65afe3d363SDmitri Tikhonov   tutorial
660bd32030SDmitri Tikhonov   apiref
67afe3d363SDmitri Tikhonov   internals
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690bd32030SDmitri TikhonovIndices and tables
700bd32030SDmitri Tikhonov==================
710bd32030SDmitri Tikhonov
720bd32030SDmitri Tikhonov* :ref:`genindex`
730bd32030SDmitri Tikhonov* :ref:`search`
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