Last week, when I said we had access to some of the leading experts in this business, I was not kidding.

David: Is BlackBerry email encrypted as it is transmitted over the air to and from a BlackBerry device?

Gary: Yes. Blackberry's wireless protocol includes encryption.

David: Does all email traffic coming out of all BlackBerry devices travel over the RIM network (RIM is Research In Motion, the company that makes BlackBerry)? This would seem to be the case from the big shutdown we saw last week.

Gary: Yes. Email sent from BlackBerry devices is sent through the RIM network before connecting to the Internet.

David: What is the topology and structure of the RIM network? Where do BlackBerry Enterprise servers, Lotus Domino servers, and Exchange servers figure in this topology?

Gary: RIM's network topology is proprietary to RIM. BlackBerry Enterprise servers are software products companies buy. They are then installed on the company networks. You do not need a BlackBerry Enterprise server to use email on a BlackBerry. Many carriers (T-Mobile, Verizon, etc.) allow email accounts on their networks to store email instead of an Enterprise server.

David: How does BlackBerry traffic that comes from phone carriers and ISPs like AOL differ from other BlackBerry traffic? In other words, do we need to consider where Mr. Rove gets his BlackBerry or do they all work the same?

Gary: All BlackBerry devices work the same, but some offer more features than others. Email is transmitted via RIM's network. Additional features, like Web browsing, use different protocols (e.g., GPRS [General Packet Radio Service]). Some functionality (like cell phone usage on a BlackBerry) uses the cell carriers network (Cingular, T-Mobile, etc.).

David: Is there any known data logging that occurs on the BlackBerry network? Do RIM's servers or any other servers log emails sent through them? What are the constraints of those logs (how long, how big, how often)? In other words, is there any chance we'll find any of those allegedly missing email messages somewhere on a BlackBerry server?

Gary: No publicly-known accounting is done on the RIM network in terms of whose email went where. The emails that were stored on the email server for the RNC could be accessed via an email client on a computer or a BlackBerry. These are the ones that were "deleted by mistake."

David: Can one BlackBerry send and receive from different email accounts? Is it more likely that Mr. Rove has one BlackBerry for his White House account and another for his RNC account or is he more likely to have a single device for both? How does the device get configured for choosing accounts to send and receive? And, if he does have one, does the traffic from both accounts run through the same servers and server infrastructure?

Gary: BlackBerry devices can be made to retrieve email from multiple accounts depending on the software in the BlackBerry and the configuration of the mail servers. How Karl Rove's email was configured and how it was routed is unknown.