+--------+
                                        >PP    |        |  <PP
                                    ,----------|  idle  |----------.
                                    |          |        |          |
                                    v          +--------+          v
                             +----------+          |           +----------+
                             |          |          | <H        |          |
                         ,---| reserved |          |           | reserved |---.
                         |   | (local)  |          |           | (remote) |   |
                         |   +----------+          |           +----------+   |
                         |      |                  v                   |      |
        +---------+      |      | >H           +--------+           <H |      |      +---------+ 
        |         |      |      |       <H(S)  |        | >H(S)        |      |      |         |
        | quarter |<---- | ---- | -------------|        |------------- | ---- | ---->| quarter |
        |  closed |      |      |              |        |              |      |      | closed) |
        | (remote)|      |      |       <H(SH) |  open  | >H(SH)       |      |      | (local) |
        +---------+      |      |        <D(S) |        | >D(S)        |      |      +---------+
         |   |  |        |      |           <R |        | >R           |      |        |  |   |
    <C(H)|   |  |>H(S)   |      |    ,---------|        |---------.    |      |   <H(S)|  |   |>C(H) 
         |   |  |        |      |    |         +--------+         |    |      |        |  |   |
         |   |  |        |      |    |                            |    |      |        |  |   |
         |   |  |        |      |    |         +--------+         |    |      |        |  |   |
         |   |  '------- | ---- | -- | ------->|  two   |<------- | -- | ---- | -------'  |   |
         |   |           |      |    |         |quarters|         |    |      |           |   |
         |   |           |      |    |         | closed |         |    |      |           |   |
         |   | >H(SH)    |      |    |         | (local,|         |    |      |     <H(SH)|   |
         |   | >D(S)     |      |    |         | remote)|         |    |      |      <D(S)|   |
         |   | >R        |      |    |         +--------+         |    |      |         <R|   |
         |   |           |      |    |            |  |            |    |      |           |   |
         |   |           |      |    |      <C(H) |  | >C(H)      |    |      |           |   |
         |   |           |      |    |            |  |            |    |      |           |   |
         |   |           |      v    v            |  |            v    v      |           |   |
         |   |           |   +----------+         |  |         +----------+   |           |   |
         `-- | --------- | ->|   half   |<--------'  '-------->|   half   |<- | --------- | --'
             |           |   |  closed  |                      |  closed  |   |           |
             |           |   | (remote) |                      | (local)  |   |           |
             |           |   +----------+                      +----------+   |           |
             |           |        |   |                          |   |        |           |
             |           |        |   |>H(S)                <H(S)|   |        |           |
             |           |        |   |                          |   |        |           |
             |  ,------- | ------ | - | -------------------------'   |        |           |
             |  |        |        |   '----------------------------- | ------ | -------,  |
             |  |        |        |                                  |        |        |  |
             v  v        |        |                                  |        |        v  v
        +---------+      |        |                                  |        |      +---------+
        |  three  |      |        | >H(SH)                    <H(SH) |        |      |  three  |
        | quarter |      |        | >D(S)                      <D(S) |        |      | quarter |
        | closed  |      |        | >R                            <R |        |      |  closed |
        |(remote) |      |        |                                  |        |      | (local) |
        +---------+      |        |            +--------+            |        |      +---------+
             |           |        `----------->|        |<-----------'        |           |
             | <C(H)     `-------------------->| closed |<--------------------'     >C(H) |
             '-------------------------------->|        |<--------------------------------'
                                               +--------+
      
      
<        : receive frame
>        : send frame
H        :  HEADERS frame (with implied CONTINUATIONs)
PP       : PUSH_PROMISE frame (with implied CONTINUATIONs)
D(S)     : DATA frame with END_STREAM flag
H(SH)    : HEADER frame with END_STREAM and END_HEADER flags
H(S)     : HEADER frame with END_STREAM flag
C(H)     : CONTINUATION frame with END_HEADER flag
R        : RST_STREAM frame