427-0089-00-12 Version 100
July 2016
41
3
Advanced Configuration
By default, the video streams from the camera
are sent using unicast packets rather than
multicast. This means a given packet of IP Video
will be sent separately to each client that has that
video stream open. Therefore each additional
client will cause the bandwidth to increase and
cause more overhead on the system in
comparison to multicast.
With Multicast enabled, new fields are shown,
Destination Network IP address and Destination
Port, as well as TTL (time-to-live). If more than
one camera is providing multicast streams on the
network, be sure to configure each stream with a
unique multicast Destination Network IP address
and Destination Port combination.
The time-to-live field controls the ability of IP packets to traverse network or router boundaries. A
value of 1 restricts the stream to the same subnet. Values greater than 1 allow ever increasing
access between networks.
With Multicast enabled, video packets are shared by streaming clients, so additional clients do not
cause bandwidth to increase as dramatically. If the video streams are used by more than one client/
location, it may be wise to use multicast for more efficient bandwidth usage.
There are some challenges with streaming video over an IP network, when compared to other
traditional IP applications which are less time-critical, such as email and web browsing. In particular,
there are requirements which must be fulfilled to ensure satisfactory video quality in professional
security environments. There are many parameters and factors related to network infrastructure,
protocols, codecs, and so on that can affect the quality and bit rate of a video stream when it is
established between the camera and a client.
The video streaming is done using a protocol generally referred to as Real-time Transport Protocol
(RTP), but there are actually many protocols involved, including Real-Time Transport Control
Protocol (RTCP) and Real Time Streaming Protocol (RTSP). In the background, a “negotiation” takes
place to establish a session between the client (such as FLIR Latitude, or a third party VMS or video
player) and the camera. The ports which form a session are negotiated using a protocol such as
RTSP. A client typically requests a video stream using its preferred settings, and the camera can
respond with its preferred settings. As a result, many of the details are established dynamically, which
may run contrary to network security requirements.
In some networks, the RTP/RTSP traffic is carried (tunneled) over Hypertext Transfer Protocol
(HTTP) as that may allow the traffic to cross network boundaries and firewalls. While this method
involves more overhead due to encapsulation, it may be necessary for clients to access the video
streams when HTTP proxies are used.
RTSP is originated and received on even port numbers and the associated RTCP communication
uses the next higher odd port number; the default RTSP Port is 554.
The default value for the stream from VIDEO - 0 is ch0. For example, the complete connection string
is: rtsp://192.168.250.63/ch0. This stream name can be used to open a video stream with a third-
party video player. By default the video stream uses the IP address of the camera.
