Comtech EF Data CMR-5975 Manual - Manual (Page 95)

Digicast Media Router S2 Receiver CMR-5975 (MR-S2) Revision 3
IP Routing Support MN-CMR5975-IOM
B–3
Figure B-1. Multicast Mapping (IP to MAC)
B.3 Section Packing
Section packing is a technique utilized to provide more optimal utilization of the MPEG-2
transport stream (TS) packet structure. When section packing is not used, each TS packet
(containing the MPE section) can carry no more than a single section. This often results in wasted
payload capacity when the sections are less than 184 bytes.
The section packing feature allows more
than a single MPE section to be carried
by an MPEG-2 TS packet, thereby
minimizing wasted payload capacity.
In the case of a large MPE section that
spans multiple MPEG-2 packets, the
ending of an MPE section may occur in
the middle of an MPEG-2 packet. In
this instance, with section packing, a
new MPE section begins immediately
after the first MPE section has finished
without any ‘fill’ (wasted) bytes having
to be inserted before the start of the next
MPEG-2 packet.
Figure B-2. Section Packing