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+## Pull Protocol (_PULL_)
+
+The ((_pull_ protocol))(((protocol, _pull_))) is one half of a ((pipeline pattern)).
+The other half is the xref:push.adoc[_PUSH_] protocol.
+
+In the pipeline pattern, pushers distribute messages to pullers.
+Each message sent by a pusher will be sent to one of its ready peer pullers, chosen in a round-robin fashion.
+This property makes this pattern useful in ((load-balancing)) scenarios.
+
+#### Socket Operations
+
+The xref:nng_pull_open.adoc[`nng_pull_open`] functions create a puller socket.
+This socket may be used to receive messages, but is unable to send them.
+Attempts to send messages will result in `NNG_ENOTSUP`.
+
+When receiving messages, the _pull_ protocol accepts messages as they arrive from peers.
+If two peers both have a message ready, the order in which messages are handled is undefined.
+
+#### Protocol Versions
+
+Only version 0 of this protocol is supported.footnote:[At the time of writing, no other versions of this protocol have been defined.]
+
+#### Protocol Options
+
+The _PULL_ protocol has no protocol-specific options.
+
+#### Protocol Headers
+
+The _PULL_ protocol has no protocol-specific headers.