Data Network Redundancy
Redundancy
NOTE :
Both outputs of a pair are active at the same time, therefore the use of primary and secondary ports is meaningless in
this configuration.
The four Ethernet data ports operate as two redundant pairs. Data 1 and 2 (Ge1 with Ge2), and Data 3 and 4 (Ge3 with Ge4).
When an output transport stream is defined, it is assigned by the user to one or other data output pairs.
Both ports are independent of each other i.e. the IP address, MAC address, subnet mask and default gateway can have different
settings. Both ports are active at the same time and transmit the same data. If both ports are configured to be on the same subnet,
only one port will respond to ICMP messages.
The data ports can raise an alarm during abnormal operational conditions, (see Looking After the Unit > Troubleshooting > Handling
Alarms >
Alarms - Data Port
).
IP Encapsulation of MPEG Transport Streams
This topic describes how an MPEG-2 transport stream is carried over an IP link.
Between one and seven MPEG transport stream packets are carried in a UDP packet. The UDP packet may optionally also contain an
Real Time Protocol (RTP) header, which adds additional information such as a sequence number and a timestamp, which can help in
the detection of packet loss across a network.
The UDP header is 8 bytes long, and the RTP header is 12 bytes long.
The network layer protocol is IPV4, which adds a 20 byte header to every packet.
The physical link layer is then Ethernet at either 100 Mbps or 1000 Mbps.
Configuring an Output Transport Stream
Overview
1 to 7 MPEG Transport Stream Packets
RTP Header (optional)
UDP (User Datagram Protocol)
IP (Internet Protocol)
Ethernet (IEEE 802)
© Ericsson AB 2011. All rights reserved
© Ericsson AB 2011. All rights reserved
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