48 lines
2.0 KiB
ReStructuredText
48 lines
2.0 KiB
ReStructuredText
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Frequently Asked Questions
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API/Design
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==========
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*Why have a separate engine for server and client? Surely traffic
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could be differentiated as much as it needs to be internally in one
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engine?*
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The traffic *cannot* be differentiated for gQUIC versions Q046 and Q050.
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This is because in these versions, the server never includes a connection
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ID into the packets it sends to the client. To have more than one
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connection, then, the client must open a socket per connection: otherwise,
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the engine would not be able to dispatch incoming packets to correct
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connections.
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To aid development, there is a :macro:`LSQUIC_FORCED_TCID0_VERSIONS` that
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specifies the list of versions with 0-sized connections. (If you, for
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example, want to turn them off.)
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Once gQUIC becomes deprecated in the future, there will remain no technical
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reason why a single engine instance could not be used both for client and
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server connections. It will be just work. For example, the single
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engine settings :type:`lsquic_engine_settings` will have to be separated
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into client and server settings, as the two usually do need to have
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separate settings.
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Example Programs
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================
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*http_client does not work with www.google.com, www.facebook.com, etc.*
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Check the version. By defaut, ``http_client`` will use the latest supported
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version (at the time of this writing, "h3-31"), while the server may be using
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an older version, such as "h3-29". Adding ``-o version=h3-29`` to the
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command line may well solve your issue.
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There is an `outstanding bug`_ where lsquic client does not perform version
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negotiation correctly for HTTP/3. We do not expect this to be fixed, because
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a) this version negotiation mechanism is likely to become defunct when QUIC v1
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is released and b) version negotiation is not necessary for an HTTP/3 client,
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because the other side's version is communicated to it via the ``Alt-Svc`` HTTP
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header.
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.. _`outstanding bug`: https://github.com/litespeedtech/lsquic/issues/180
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