They're coming. Gleaming all-in-ones, metallic slimline notebooks and hand-size "mini" machines.

For network admins, the Macintosh has always been the purview of advertising agencies, entertainment companies, educators and home computer users. Mac OS X is merely a minor support issue in a Microsoft-dominated organization.

Yet as the consumer market begins to meld with the corporate world even more, and employees expect to use their preferred gadget (and operating system) for work and home life, the Mac could make inroads at large corporations.

The facts reveal a coming resurgence. Apple sold 36 per cent more Macs in the second quarter than the same quarter last year. The company has sold more than 1 million iPhones and 110 million iPods to date. There also just seems to be "something in the air" - or at least the blogosphere - suggesting a Mac resurgence. Blogs such as post about Apple constantly, and even IT analyst firms that have usually downplayed the Mac as "niche" are talking about the platform in the corporate world again.

"We expect that much of today's IT infrastructure is going to be turned upside down by the invasion of consumer technologies," said Andrew Jaquith, an analyst at Yankee Group Research. "Consumerization is going to make IT's job harder, and platforms like the Mac are going to become increasingly common, in many cases in spite of the wishes of management."

Minimal changes or maximum stress?

For the most part, connecting a Mac to a corporate LAN doesn't have a world-shattering effect on performance or support. According to William Green, director of networking at the University of Texas, the Mac has had a minimal impact on the school's infrastructure.
"All OSs behave differently; if you have a multivendor environment, you have to deal with the differences," said Green. "There have not been any special problems related to Macs."

Green did mention a few bugaboos, however, among his generally positive comments about the Mac. He said his group has seen more support issues related to the Cisco VPN for Mac than the version for Windows XP, although they have fewer support calls for the native VPN client for OS X.

"There have been problems with OS patches affecting wireless connectivity for a small portion of Mac laptops in the past - specifically related to 802.1X," he said. "Those appear to have been corrected. We have found the Mac OS X client much easier for users to configure for wireless and 802.1X. It has been a benefit not having to deal with all the third-party drivers that come from the PC/XP world since this has caused a lot of problems for XP users during our 802.1X wireless rollout."

Yankee's Jaquith mentioned another pitfall. Admins have found they can turn on the outbound firewall in Windows XP SP2 for each network adapter independently through the GUI. With OS X, however, admins have to use a command-line parameter in the OS X IPFW tool to enable the feature, turn on logging and enable stealth mode so the Mac doesn't reply to network pings.

Computer consultant Bryan Bowers at Bowers Technologies said his clients have had problems with strong network security working with the Mac, likely related to signed server message block connections. Jaquith downplayed this glitch, noting that most corporations probably don't have server security protocols set so high that the Mac operating system would have trouble accessing shares.

Bowers also mentioned his clients have trouble connecting to network printers from a Mac, and that email server configuration can sometimes prove problematic, because the servers must be reconfigured to support Internet Message Access Protocol and Post Office Protocol 3 for inbound mail and Simple Mail Transport Protocol for outbound traffic.

The fact that Microsoft hasn't updated its Entourage client for the Mac in several years suggests that its OS X support is waning, although a new Office 2008 version for the Mac with a new email client is due in January.

Jaquith mentioned that network backup support for the Mac platform could pose a problem for admins, because corporate backup tools often don't support the platform. "Some admins use a Unix command called 'rsync' to back up Mac hard drives on a scheduled basis," he said. "There are also some Mac-specific tools, like EMC's Retrospect, that I've heard work well."

For remote management, the Mac provides the Remote Management tool that works in the OS X GUI and allows admins to run AppleScripts remotely to change client settings.

Will the Macs invade?

Even with OS X-specific support tools, good compatibility with the network layers in a company and a wide range of desktop applications, the one "gorilla in the room" for widespread Mac adoption in bigger companies is the fact that many customized corporate applications won't work on the Mac.

Some companies get around this conundrum by using virtualization software from SWsoft Parallels or VMware Fusion, or by loading Apple Boot Camp on Mac computers so that end users can boot into OS X or Windows.

Jaquith also noted that companies are hesitant to introduce the Mac because they want to focus on as few operating systems as possible and, he said, "favour a monoculture in which all machines are the same." Most corporations are continually looking for ways to manage their infrastructure more consistently and measure network performance, and the Mac (and, for that matter, Linux) just introduces another variable. Many companies also prefer the "old familiar technology" that Windows XP provides.

Another common argument against the Mac is that Apple is the only hardware vendor, although many companies choose one primary hardware vendor, such as HP or Dell, to gain consistency in the environment.

Apple itself seems uncomfortable with the corporate world and doesn't actively advertise to the corporate market, suggesting the company is happy continuing life as a consumer darling and has no plans to compete with Microsoft.

If Jaquith and others are right, it's the consumer who will bring the platform into the corporate world and, it seems, force network managers to support the operating system.

John Brandon is a freelance writer and book author who worked as an IT manager for ten years.