Server message:
=========================
       BWIDTH q4s://www.example.com Q4S/1.0
       Session-Id: 53655765
       Sequence-Number: 0
       Content-Type: text
       Content-Length: XXXX
       Measurements: l=22, j=7, pl=0.00, bw=200

       ZY0VaT1ZURlZVVmhyUFE9PQ (to complete up to max-content-
                               length UDP payload length)
=========================