Simen Frostad, Chairman of Bridge Technologies
‘If only I had known then what I know now’. Surely everyone thinks this at least once in their lifetime. For most of us, it’s probably many times more than once.
Events are usually more understandable in hindsight, with perspective and a fuller consideration of the situation than might have been possible in the heat of the action. Decisions taken under pressure, when the imperative is to take immediate action, and when the consequences are not completely clear, are sometimes not the best.
Historians can give an authoritative account of causes and effects only because they have this distance and perspective, and the time to gather in and weigh all the sources. Politicians operate in the present, and seem to think only in the short term, but there are rare exceptions: Mao Tse Tung was asked in the 1960s whether the French Revolution had been a good thing or a bad thing. ‘It’s too early to tell,’ he said.
What historians would surely love to do if they had the means would be to replay the events they are interested in, walking through them and viewing them from every angle, seeing connections and causations that might have been obscure at the time. Until someone invents a time machine – and a very sophisticated one at that – that will remain an impossibility, but something pretty similar now exists for anyone looking back in time to find out what happened to a digital media service when there was an outage.
The VBC Timeline technology developed by Bridge Technologies allows engineering teams to sit down after the dust has settled in the aftermath of an ‘acute’ event such as a service failure, and play through a timeline of all the data gathered by the entire monitoring system over the days, weeks and months before the event, seeing all the data displayed like the tracks in a non-linear editing system for movies or music.
Each monitoring parameter is visible on its individual track, and users can scrub through the data at any point in the recorded archive, opening and collapsing groups of tracks, and zooming in to observe fine detail on all the visible tracks. The timeline shows content thumbnails, alarm markers and all the metrics and status displays familiar from the monitoring system’s real-time graphical displays, making visual navigation through the data simple and intuitive. The ability to observe and play through data recorded over a period of several months or years allows users to see recurring patterns that may be invisible over a shorter timescale. By zooming out of the timeline to view longer periods of time, unsuspected correlations can be identified and examined in progressively greater detail by zooming in to a short timeframe.
Engineers can search through the chain of events that led up to service failures, and generate reports for remedial action or the fulfilment of regulatory SLA obligations. The Archive Server and Timeline capability also simplifies detailed and comprehensive reporting for regulatory verification of closed caption conformance, loudness, SCTE35 signalling, RF trending and other parameters.
The data recording is provided by a specially-developed Archive Server in a simple connect-and-forget form, with each Archive Server module able to retain years of recorded data for multiple services. When connected to the Bridge Technologies VBC controller and configured through a minimal setup routine, the Archive Server automatically activates the VBC Timeline and its historical analysis capability.
One of the most important consequences of this technology is that when users can move back and forth through a graphical representation of the historical data, they can see all the connections between complex data types, and track the way different types of data interact and indicate behaviours that are unexpected. When you can do this, it’s much easier to examine an event and arrive at a clear understanding of what really happened and what the causes were – especially if the causes have roots that are only apparent when a lengthy slice of data is available to view. As a result, engineers without a very high level of detailed knowledge can quickly get to the bottom of a problem, because the complexity of the data is visualised in a form that makes its meaning simple to comprehend.
Why is it useful for digital media service engineers to have the ability to look back and re-examine events after some time has elapsed? Precisely because in the heat of the moment, the emphasis is on solving the problem immediately, and there isn’t time to understand what really caused it. The sticking-plaster solution engineers may come up with to get a service back up might buy a little breathing space, but it doesn’t necessarily address the root cause of the failure. In fact the root cause may be almost inaccessible when engineers only have a small slice of recent data to work with. Human nature being what it is, the temptation might be to think that since it’s fixed (however temporarily), it ain’t broke. And that’s really a recipe for the next outage.
So 20/20 hindsight is now available for digital media engineers, and better service quality will be the outcome. Historians and the rest of us will have to struggle on, trying to understand causes and effects without the benefit of our own ‘time machine’.
Published by Broadcast Beat on page 215