NCast PR-HD - Manual (Page 39)

NCast Presentation Recorder Reference Manual
The Maximum Transmission Unit (MTU) is the maximum length of a packet and is normally set to 1500. For
some special circuits (satellite links, others) the maximum size may need to be adjusted downward to avoid
packet fragmentation, which leads to inefficiencies and possible packet loss.
5.7.2. Enable Video Bandwidth Smoothing
If enabled, the encoder smooths the stream transmission and sends packets at the prescribed target bit rate
(this is the default setting). This will increase network jitter and latency. If disabled, the encoder uses burst
transmission by sending all packets immediately after encoding. This will significantly decrease network jitter
and latency, but, depending on network connection, it can cause packet loss and bottlenecks. If burst
network transmission is acceptable, it is possible to disable this option to get extra low video latency. This is
a video encoder option - it doesn't affect the decoder.
5.7.3. Set Max Audio Frames in Packet
Sets how many AAC frames can be sent in one packet. The default value is 8. The valid range is from 1 to
10. Lower values result in lower network jitter and lower latency, but higher network overhead (each packet
contains additional headers). Set to 1 to achieve extra low audio latency. This is an audio encoder option - it
doesn't affect the decoder.
5.7.4. Set TTL
The time-to-live defines the number of router hops that will be valid for a packet. When the number of hops is
exceeded, the packet is discarded. The minimum value for this field is 1, and a value of 127 or greater
should be used for global transmission.
In some multicast networks TTL defines the “scope” or boundary conditions for containment of the multicast
traffic flow. The following table lists commonly accepted values of TTL used in this manner.
TTL Scope
0 Restricted to the same host. Won't be output by any interface.
1 Restricted to the same subnet. Won't be forwarded by a router.
<32 Restricted to the same site, organization or department.
<64 Restricted to the same region.
<128 Restricted to the same continent.
<255 Unrestricted in scope. Global.
TTL scopes, however, have fallen into disfavor, and current practice recommends use of administratively
scoped addresses for containment of multicast traffic flows.
5.8. E
DIT
C
HANNEL
– RTMP S
TREAMING
5.8.1. Set RTMP Server Address
This Channel Type enables use of the RTMP (Flash Streaming) protocol for live broadcast to a streaming
server or CDN. Enter the name of the server or its IP address followed by the name of the application
instance used for this broadcast.
NCast Corporation Revision 2.2
Page 39