Not All- & w=expected +---+   +---+w = Not expected
 ~~~~~~~~~~~~~~~~~~~~~ |   |   |   |~~~~~~~~~~~~~~~~
 Set lcl_bm(FCN)       |   v   v   |discard
                      ++===+===+===+=+      
+---------------------+     Rcv      +--->* ABORT
|  +------------------+   Window     |
|  |                  +=====+==+=====+  
|  |       All-0 & w=expect |  ^ w =next & not-All
|  |     ~~~~~~~~~~~~~~~~~~ |  |~~~~~~~~~~~~~~~~~~~~~
|  |    set lcl_bm(FCN)     |  |expected = next window
|  |      send lcl_bm       |  |Clear lcl_bm
|  |                        |  |    
|  | w=expected & not-All   |  |
|  | ~~~~~~~~~~~~~~~~~~     |  |
|  |     set lcl_bm(FCN)+-+ |  | +--+ w=next & All-0
|  |     if lcl_bm full | | |  | |  | ~~~~~~~~~~~~~~~
|  |     send lcl_bm    | | |  | |  | expected = nxt wnd
|  |                    v | v  | |  | Clear lcl_bm
|  |w=expected& All-1 +=+=+=+==+=++ | set lcl_bm(FCN)
|  |  ~~~~~~~~~~~  +->+    Wait   +<+ send lcl_bm
|  |    discard    +--|    Next   |   
|  | All-0  +---------+  Window   +--->* ABORT  
|  | ~~~~~  +-------->+========+=++        
|  | snd lcl_bm  All-1 & w=next| |  All-1 & w=nxt
|  |                & RCS wrong| |  & RCS right
|  |          ~~~~~~~~~~~~~~~~~| | ~~~~~~~~~~~~~~~~~~
|  |            set lcl_bm(FCN)| |set lcl_bm(FCN)
|  |                send lcl_bm| |send lcl_bm
|  |                           | +----------------------+
|  |All-1 & w=expected         |                        |
|  |& RCS wrong                v   +---+ w=expected &   |
|  |~~~~~~~~~~~~~~~~~~~~  +====+=====+ | RCS wrong      |
|  |set lcl_bm(FCN)       |          +<+ ~~~~~~~~~~~~~~ |
|  |send lcl_bm           | Wait End |   set lcl_bm(FCN)|
|  +--------------------->+          +--->* ABORT       |
|                         +===+====+=+-+ All-1&RCS wrong|
|                             |    ^   | ~~~~~~~~~~~~~~~|
|      w=expected & RCS right |    +---+   send lcl_bm  |
|      ~~~~~~~~~~~~~~~~~~~~~~ |                         |
|       set lcl_bm(FCN)       | +-+ Not All-1           |
|        send lcl_bm          | | | ~~~~~~~~~           |
|                             | | |  discard            |
|All-1&w=expected & RCS right | | |                     |
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~ v | v +----+All-1         |
|set lcl_bm(FCN)            +=+=+=+=+==+ |~~~~~~~~~     |
|send lcl_bm                |          +<+Send lcl_bm   |
+-------------------------->+    END   |                |
                            +==========+<---------------+

       --->* ABORT

       In any state
          on receiving a SCHC ACK REQ
             Send a SCHC ACK for the current window