Like many companies, car rental firm Avis Europe is facing the prospect of migrating from Windows XP to Windows 7. Avis runs distributed IT operations, which means it has quite a broad range of applications, a number of which are browser-based.
Microsoft is stopping development of Internet Explorer 6. Support for Windows XP and IE6 will end on 14 April 2014, driving all enterprises to migrate to Windows 7.
Given the 2014 time bomb on XP support, David Beshaw, head of IT operations at Avis Europe, did not want to be stuck on an unsupported operating system. But IE6 will not run directly on Windows 7, so to upgrade the operating system (OS), he needed a way to support the legacy applications and websites that Avis uses to operate its business.
“We encountered some applications which do not work on later versions of IE,” he says. “We did not want to expend development effort to rework these applications. Changing from one browser to another offers no perceived benefit from a business perspective.”
While IT benefits from improvement in security, the business only sees the cost of the upgrade, which is something he wanted to avoid. “There is a lot of focus to get maximum value out of IT. We want to concentrate our efforts on changes in the business rather than keeping the lights on,” said Beshaw.
When users first started building web applications, no one imagined that the browser would be less compatible than the operating system as HTML was supposed to make applications compatible. “We did not foresee that browsers would change quicker than the operating system. It is hard to say how many applications run in the browser, but around 10% of our applications are not compatible with IE7/8.”
Avis considered swapping browsers, to use either Firefox or Chrome, but IE6 still offers the controls corporates need, such as the ability to manage patches outside the supplier’s patch cycle.
Given that not all applications were incompatible, Beshaw had a choice: “Either we fix the applications, stay with XP or implement a compatibility product.”
Reworking incompatible applications was not an option. “In terms of cost analysis, we were talking about weeks of redevelopment time,” he says. “For even a simple application, you would lose man-weeks of development effort.”
Desktop virtualisation was an option, but virtualising IE6 is not the most efficient use of virtualisation.
Beshaw says Avis is moving towards virtualisation, but it is a long-term project. He wants to move off IE6, rather than risk fragmenting the user base by attempting to keep IE6 running on some users’ XP machines, while others migrate to IE7/8 and Windows 7.
Avis has had some experience of virtual desktop infrastructure (VDI). “We have already invested months of effort looking at the VDI market,” says Beshaw. “We had a lot of problems a few years ago as an early adopter on a small project. We now have a fairly large virtualised server [farm], but not much VDI.”
Avis selected Browsium’s UniBrows compatibility product to keep its IE6 applications running in Windows 7. “Browsium allows us to move to Windows 7 without going to a far bigger project to go into virtualisation,” says Beshaw.
The software runs on the PC client and determines whether an application requires the IE6 browser engine. From a user perspective, the application runs in an IE8/9 tab, but renders using the 32-bit IE6 engine rather than IE8/9. UniBrows loads relevant IE6 ActiveX controls, such as specific versions of Adobe Flash or the Java Runtime Engine.
Avis deploys IE8 and UniBrows. “The user sees an IE8 browser. We then configure centrally sites that are IE6-only, and UniBrows will recognise it’s IE6 and will do the emulation,” Beshaw says.
Avis Europe runs more than 4,000 Windows XP PCs across Europe. “We are starting to put in Windows 7, regardless of our virtualisation project. UniBrows will help us along this route as an interim step.”
As an added benefit, Beshaw says UniBrows has a test mode, which developers at Avis can use to check that their code works on different versions of IE.
This was first published in November 2011