Dealing with extremes

The highs and lows of broadcast networks

Microbursts are the stealth destroyers of good network health. In this article we explore why microbursts are a problem, and how they can be effectively managed.

The rocky path ahead
Keen hikers will know that when you gaze across the horizon at the beginning of your walk, what you see initially is never what you get when you’re out on the trail. What appeared from a distance to be a few gentle ascents and descents in reality turns out to be an endless series of undulations, with some of the biggest peaks hiding just out of sight. Planning when to eat your energy bar becomes a much more complex consideration.

The same applies in the broadcast world. What appears to be a well-performing, within-range readout of network performance can in fact disguise a multitude of sins, all of which have the potential to significantly disrupt audience experience. The frustration engineers feel when they stare at a blank preview screen whilst their technical readouts suggest everything is A-OK must be seen to be believed.

The law of averages
The reason for this contradictory occurrence has to do with what is measured in broadcast networks, and how it is displayed. Traditional network traffic measurement instruments often rely on average metrics over a second to assess network performance. This results in a ‘smoothed-out’ curve that comfortably sits within set parameters.

In reality though, a network could be subject to ‘microbursts’, a phenomenon in which data packets are transmitted in rapid, oversized bursts. Although these constitute only momentary fluctuations, they have the potential to overflow the buffers of the network stack, undermining broadcast quality. Thus, a per-second readout of network performance may indicate that – on average – everything is operating within parameters, when in reality the broadcast is subject to jitter and dropped packets. Indeed, a network showing an average rate of 4 gigabits per second may experience microsecond-level peaks reaching as high as 25 gigabits.

Examining the nitty gritty
After 20 years developing an almost-unrivalled knowledge of IP broadcast and packet behaviour, the significance of this problem was readily apparent to us at Bridge. And yet very few on the market seemed to be addressing it. For this reason, we developed our Microbitrate monitoring technology. By addressing this issue at the microsecond level, Bridge Technologies’ Microbitrate feature helps engineers to pinpoint the exact moments and causes of microbursts, facilitating immediate and effective troubleshooting.

Whilst the core functionality of Bridge Technologies’ Microbitrate analytics has been integrated into the IP probes for over six years, it undergoes continuous evolution with each new version release, providing increasingly intuitive and in-depth visualisations of network traffic peaks and troughs. This helps engineers to address the problems inherent in the traditional ‘average-value’ metrics that other monitoring probes rely on.

Delivering the right level of insight for the job
In many ways, Microbitrate analytics is just an extension of our overall focus on micro-level detail. Bridge probes are designed to understand network performance across every imaginable metric, at incredible levels of detail. The specificity and level of insight that can be gained on network performance is quite remarkable.

But our guiding mantra has long been ‘making the complex simple’. It’s crucial that this level of detail is accessible; tailored to both the user and the job at hand. Intuitive, flexible presentation is as important for broadcast tool design as the underpinning technology that supports it.

This was a key consideration for us as we have evolved our Microbitrate analytics. We grant users the ability to customise the time increments at which measurement is undertaken, so that they can view performance on the micro- and macro-level, adjusting it to the task and level of insight needed.

When it comes down to it, thinking big often requires thinking small. IP has transformative potential for the whole broadcast industry, but harnessing its power involves taming its micro-complexities. Bridge’s Microbitrate analytics technology does exactly that.