A__mic8 / A__digital8 User Guide
Version: 10.0.0/4
10/66
5. The Streaming Ports
5.3
SMPTE 2022-7, Seamless Protection Switching (SPS)
SMPTE 2022-7 is a method of recovering lost data packets when streaming data over an IP network. The
technology is also known as Seamless Protection Switching (SPS). Within a RAVENNA installation, it can be
used to provide main and redundant paths for audio/video streams and PTP synchronization.
Compatible Devices
Lawo devices that support SMPTE 2022-7 are:
·
981/61 RAVENNA IO module - fitted to the Nova73, Nova37, mc
2
36 and mc
2
Micro Core.
·
mc
2
56 MKIII and mc
2
96 Local IO.
·
A__line devices: A__mic8, A__digital8, A__madi4, A__stage48, A__stage64, A__stage80.
·
Power Core
RP
(for mc
2
/Nova Remote Production).
·
Radio consoles: ruby / Power Core, crystal / Compact Engine.
·
Virtual radio applications: R3LAY VRX
4
, R3LAY VRX
8
and R3LAY VPB.
SMPTE 2022-7 is supported from mc
2
/Nova Version 5.14.0 and Image Version 10.0.0.x onwards.
Concept
The diagram below illustrates the concept in a standard data network:
A SMPTE 2022-7-enabled transmitter duplicates the input stream and sends it via two different paths to the
destination receiver. The receiver (also SMPTE 2022-7 enabled) combines the streams from both paths and
reconstructs the original stream. If a packet was lost on path 1, the packet is taken from path 2. If path 1 is lost
completely, then the entire stream is taken from path 2, and vice versa. The result is that the receiver can switch
from one path to the other without impacting upon the stream content.
Configuration
To configure SMPTE 2022-7 within a RAVENNA streaming network, will need to create the two separate paths for
each data stream. This means doubling the network's infrastructure and then connecting each sending and
receiving device to both paths. Within Lawo systems, the two paths are usually known as the primary (red) and
secondary (blue) networks.
For the A__mic8 / A__digital8, the two streaming paths can be created by connecting both of the
ETHERNET A
and
ETHERNET B
ports to the network, and using the RAVENNA Web UI to configure main and redundant
streams.
