Daryl Cornelius, Spirent enterprise director reveals how network testing is quietly supporting the retail sector

Daryl Cornelius, Spirent enterprise director reveals how network testing is quietly supporting the retail sector

Queues for checkout have been getting shorter in a number of the UK’s largest retail outlets, because companies have studied what happens to cause cashpoint transaction delays at peak periods, according to Cornelius of Spirent, a test, measurement and service assurance solutions provider.

He said: “Network test devices such as Spirent’s Avalanche series can be used to generate large volumes of realistic network traffic and monitor the result to pinpoint bottlenecks or contentions in the system, rather than imposing a forklift upgrade of the whole network.

Maximising network investment

“In some cases the solution is to upgrade – not the whole network but just a device or section that was causing the delay – but often it is just a question of ‘tuning’ the network to go faster. What these retailers found was that checkout transactions were not being sufficiently prioritised in their networks – that the cashpoint link to the credit company was having to compete with other vital, but less time critical, traffic such as stock update data.”

According to Cornelius, the solution was simple: “Give cashpoint traffic the top priority on the network and it goes straight to the external link. Result: less delay, shorter queues, happier shoppers, faster sales, bigger profits.

“Network testing is not just a question of piling massive amounts of traffic onto the network, because most real life network traffic comes in bursts of overlayed patterns. A trained and experienced tester can save time and expense by knowing what to look for, however sophisticated test devices can go a long way to creating realistic conditions by sampling everyday traffic and multiplying to simulate real rush traffic.

Understanding transactional traffic

“Every transaction has its own pattern, dictated both by the technology and its protocols and by the human operator. The credit card checkout process is not just a homogeneous burst of data – there is a pause as the device is handed to the customer for the PIN number, a typical pattern of tapping in four numbers and then the OK button, and so on.

“Realistic traffic emulation means not just reproducing the total data quantity but also this time-profile. Each type of traffic on the network – staff emails, website interactions, stock updates etc. – has its own pattern that could conflict with other types. Superimposing realistic traffic profiles is the only truly realistic test. Then the device will deliver a detailed report, identifying weak points in the network, or where to set up further tests to identify the problem.

“Network testing is a low profile activity, done overnight, so staff and customers are not aware that anything has changed – just that the retail experience has improved.

Expanding instore burden

“There are other more direct ways to please customers and increase profits – loyalty cards, special offers, in-store announcements, and redecorating the store. More futuristic solutions include screens on trollies that announce goods suiting your shopping profile as you pass them, and mobile phone marketing linked to location data. Every such solution will have some impact on the company network – at the very least by increasing sales and altering the traffic – while intelligent multimedia trollies could add a massive bandwidth burden.

“In every case the question is the same – are you sure the system can support the solution, and manage the consequences in terms of customer traffic? And in every case the only answer will be to pre-test the system thoroughly under realistic traffic loads and conditions.

“I know this is so, because that is what my company does,” he concluded. “And we already have an impressive array of major retailers on our customer list.”