"I go into stores and I peer at their terminals. I did it in passport control the other-day and had a telling off," he chuckles.
Khan is certainly familiar with passport checks, with Specsavers' central operations being based on Guernsey, where the company was founded by husband-and-wife optometrists Doug and Mary Perkins 24 years ago. Specsavers is the island's largest private employer, employing 650 people out of a population of 60,000, and despite some limitations of island life, there are no plans to move IT operations or the global datacentre wholly to the UK.
"There are challenges. Guernsey is an island, so it has a finite work pool. Telecommunications links are finite too, although with the Vanco network we're able to get much more bandwidth.
"Getting on and off the island can be difficult, the fog comes in, flights are cancelled and you can be locked in for an extra day or two. The ferries can't run in bad weather either. There's no pattern to it."
Khan's central IT team is split between two bases. Thirty members of staff on Guernsey run the datacentre and provide IT support for the headquarters. Across the channel in Southampton, 120 people make up the global support team, providing business analysis and retail expertise to develop the software for each country.
In addition, each territory has a small IT unit of 10-20 people comprising a service desk team with business analysis skills and its own datacentre, which is linked back to the central systems on Guernsey. The common software and hardware components of Specsavers-in-a-Box mean that any upgrades can be pushed out of the UK hub and made live worldwide in one go.
The central datacentre itself has a combination of Fujitsu and Sun servers. There are no Fujitsu engineers on site, but the company is tied to a conventional SLA. A monitoring arrangement means Fujitsu can watch the servers and alert Khan's team to any problems. Specsavers' own staff can make minor hardware repairs, but anything more serious and Fujitsu engineers have to cross the Channel.