Both Blue Coat's Li and Internode's John Lindsay point to the changing security landscape as a key cause of concern in the switch to a new protocol; after all, IPv6 is a whole new language.
"You need to be taking a long hard look at what your firewalls can support," Lindsay says. "Just turning on v6 is often not an option in a corporate managed desktop, largely because of how much stuff looks at v6.
"At the end of the day when you find yourself without a v4 address that you can allocate to a server or a customer, then your business growth comes to a screaming halt."
It may not be an apocalypse as such, but the historically slow behemoths of enterprise must act quickly to avoid falling behind.
When scarcity bites
Though IPv4 addresses have so far lacked any real value of themselves, their increasing rarity is likely to change that. Financial markets are inevitable in a migration to IPv6, according to APNIC's Geoff Huston, but it is important to block potential black markets from appearing.
"There'll be folk for whom the need is still desperate," he says, referring to some companies' continued need for IPv4 addresses.
Several industry watchers have warned of companies and individuals unloading excess IPv4 addresses, selling them to available buyers - even multiple times for a single address.
"If you have chaos in addressing, sending a packet into the network because a game or roulette because you don't know who's got that address on any particular day or if it's even unique," Huston says.
In an attempt to mitigate such attempts, and keep any financial markets 'white', APNIC has established a transfer registry allowing address holders to advertise such moves.
"As to how much money changes hands and how buyer and seller manage to interconnect - we're not running a trading floor - but as a registry we're well and truly aware of the fact that as we stop giving away addresses, markets will exist," Huston says.
There's no guarantee that such a registry will completely eradicate posing problems, however.
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