Yikes! CEO's and VP's cringe at the thought of this expensive yet virtually required endeavor. However, anyone with any sense of self-survival and experience will tell you to make a plan for some sort of off-site backup.
Taking this subject seriously can literally save an entire organization in the event of any number of disasters. This is why I stress that it's a "required" process for Network Administrators to understand and appreciate.
Fires, floods, tornadoes, earthquakes, or any number of disasters could happen anywhere and anytime. Disasters don't just happen to other businesses, they can happen to yours too!
Large organizations have a responsibility to plan and prepare for this possibility. If your department has not already taken the time to explore this, then this could be a great opportunity for you to develop and propose just such a plan. You should get the ball rolling and remember that a disaster does not have to turn into a crisis.
Consider your strategy thoroughly and remember that this is not strictly an IT endeavor. There will need to be an interdepartmental, cross-organizational plan put into place. Often this will require coordination between a host of internal and external departments in order to actually relocate an entire operation in a day or two.
Rest assured, it can and has been done by very large organizations in the past simply because they had a tested and established Damage Recovery Process (DRP) in place. Research and training is the key to perfecting any effective DRP.
In the event of a catastrophe, most likely, the IT department will not only be responsible for getting the entire enterprise communications back bone back up and running, but they will also need to reconnect the remainder of the network infrastructure including email-services, web-hosting, data-storage, call center telephone systems and possibly a host of other resources essential to a functioning business.
Some points to consider, your DR plan should be robust without being exorbitant. From a business perspective, not all of your data is worth protecting. You will need to measure the risk of losing it all against the cost of recovering or recreating it. Given the costs associated with information recovery compared to the costs of disaster preparation, being prepared will typically far outweigh the expense of recovering.
You'll want to consider this topic seriously and perhaps look into a third party, off-site solution. You should consider a support company like Sungard and All Covered or IBM's Business Continuity and Recovery Service. These are all excellent solutions that offer a broad selection of offsite and fallback centers. You can also research other providers at Information-Providers.com.
In summary, whichever way you choose to approach these issues, you should provide for flexibility in design for future considerations. So whether you're just starting as a Network Administrator for a large company, considering moving to a new one, or are comfortable in your current employment, you owe it to yourself and your company to familiarize yourself with these topics.
Asset Management and Disaster Recovery are here to stay. It's your job to make sure that the same can be said about your network.
Network Related Q&A Forum
WLAN related Discussion
Asset Management Options
Disaster Recovery Related Discussion