-- binary
04 09 # version, type
00 0c # length
12 34 56 78 # xid
00 02 # flags
ff ff # miss_send_len
-- python
ofp.message.set_config(
    xid=0x12345678,
    flags=ofp.OFPC_FRAG_REASM,
    miss_send_len=0xffff)