Few, if any, enterprise technology planners have not had to prepare plans of some sort for disaster recovery. This year, those plans also include planning for the impact of the flu pandemic, where business continuity might require extensive work-at-home support.
But analysts at Gartner (News - Alert) say those plans may be unworkable at some level because residential bandwidth will face huge congestion issues if a flu pandemic actually forces lots of people to work from home.
According to the Center for Disease Control, the rule of thumb for pandemic planning is that 40 percent of the workforce will not be in the workplace for an extended period of time.
“All of the telecommunications carriers say their wide area networks can handle the added capacity of a 40 percent increase," says Eric Paulak, Gartner managing VP. But the network cores typically are not the congestion drivers, the access network is the problem.
“Within the switching office, surges in demand will overload the local connection to the backbone networks, because carriers typically do not design for excess residential capacity,” says Paulak.
You might think an increase in at-home work would not unnecessarily strain the residential network, which is engineered for evening peak load. The problem is that, in a pandemic, consumer Internet usage during the day--normally an "off peak" period--will grow, mainly because children will be home from school, and will put the expected load on the network during the day that they typically impose during the evening. All of that will happen as business users also unexpectedly are adding load to the network.
As broadband access networks are engineered using an "oversubscription" rule, there actually is never enough bandwidth to handle all the demand every single user might impose, at one time. Instead, there is sharing of bandwidth that is one fifth, one tenth or one twentieth of what peak demand would be if every single customer was online, all at once.
“The network edge will crash," Paulak warns. The carriers are encouraging organizations to use third-generation or other non-tethered access as a backup solution, but those networks might overload as well, says John Girard, Gartner VP.
So what can enterprises do?
In some cases, IT organizations are loading WAN optimization controller software on employee notebooks, which should help mitigate the bandwidth and latency issues. On a congested network, a software-based WOC can make the most of the little bandwidth available with 80 to 90 percent reductions for many applications, Gartner says.
If it’s only necessary to accelerate browser-based applications, or if software cannot be installed on an employee's home computer, a second solution is to use client applets that work with data-center-resident application delivery controllers or WOCs.
A third solution is to bypass the wired last mile altogether and switch to a wireless connection, such as 3G or WiMAX (News - Alert), or satellite. However, while last-mile bypass may fix the access network problem, it won't fix the common latency-induced problems that arise during surges of unplanned emergency access.
“The impact is that all the work-at-home strategies being implemented by organizations will likely not work,” says Roberta Witty, Gartner research VP. Enterprises can mitigate that problem somewhat by extending work hours, which will spread the bandwidth load over a wider period of time.