DekTec DTC-300 StreamXpress - Manual (Page 64)

DTC-300-SP – StreamXpress
USER MANUAL
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Broadcast address depends on the subnet and is typically the last address in a subnet.
255.255.255.255 is also a local broadcast address.
#2 IP address messaging:
This field display the status of the IP address entered. In order to playout the stream, the IP address
entered needs to be valid.
The following displays are possible:
-Address is valid (Display of the address will be blue). Streaming is possible
-Validation IP address (Display of the address will be yellow). The StreamXpress is requesting the
switch to verify if the unicast IP address is found in the network. Streaming during that time is not
possible.
-IP address not found (Display of the address will be orange). The StreamXpress indicates that the
switch responded that the destination IP address is not on the network. Streaming is not possible.
-Link is down (Display of the address will be red). The StreamXpress indicates that the Ethernet link is
down. Streaming is not possible.
#3 Port :
This field allow the selection of the destination UDP port number. The UDP port number range from
0 to 65535. Note most of the common used ports are below 1000 (Like FTP-Port 21 or HTTP-Port
80). It is advised to use port greater than 1000 to avoid potential confusion with other applications.
NOTE: Knowing the port number is required for the receiving end of the unicast or multicast.
#4 TTL :
This field allows setting the TTL (Time to Live value) in the Ethernet header.
TTL is an 8-bit field. The maximum TTL value is 255. The time-to-live value can be thought of as an
upper bound on the time that an IP datagram can exist in an Internet system. The TTL field is set by
the sender of the datagram, and reduced by every router on the route to its destination. If the TTL
field reaches zero before the datagram arrives at its destination, then the datagram is discarded.
The purpose of the TTL field is to avoid a situation in which an undeliverable datagram keeps
circulating on an Internet system. In theory, under IPv4, time to live is measured in seconds,
although every host that passes the datagram must reduce the TTL by at least one unit. In practice,
the TTL field is reduced by one on every hop.
#5 RTP/UDP :
This field allow the selection of UDP only or UDP/RTP packets. The RTP (real Time protocol) header is
an extension of the UDP header and allows adjusting of the network in order to improve the quality
of service delivery of media.
The RTP adds mostly 2 elements to the UDP header. A UDP packet counter and a time stamp. The
StreamXpress does increase the RTP counter for every packet sent and includes a packet time stamp.
NOTE: RTP is required for the use of FEC.