+
+# An example of IPv4 multicast input. Cubemap will subscribe to the given group
+# and wait for data sent by any sender to the given port.
+# pacing_rate_kbit=<number of kilobit/sec> will ask the kernel to hard-limit
+# the TCP transfer rate, including retransmits, to the given speed. (This is a
+# no-op if you do not use the sch_fq packet scheduler, which is not the default
+# but can be set in Linux 3.13 and newer using tc.) This is extremely
+# useful for reducing packet loss and thus including throughput, since it means
+# that packets arrive smoothly instead of in tight bursts, which will often
+# overload underbuffered routers and cause drops (imagine receiving a 100 kB
+# keyframe at 10gig speeds, and then having to meter it out over 5 Mbit ADSL).
+# The rate should be a bit higher than your stream bitrate to allow for retransmits.