Specifies in bytes the size of receive buffers for the specified line,
 thereby controlling the maximum size of NSP message segments that can
 be received from or forwarded to an adjacent node which has accepted
 the line buffer size.  Use a value in the range 1 to 65,535.  For
 broadcast lines, a default value of 1498 bytes is provided.  For all
 other types of lines, the default is the executor BUFFER SIZE value
 (as specified in the SET EXECUTOR command).  This parameter does not
 apply to X25 lines.