The following story is loosely based on a at-the-job-situation.

During my last year as Computer Science-student, we had a course called "Datacommunications" and as every self-respected networking course, we used Andrew Tanenbaum’s book, called Computer Networks, which in my opinion is still the best networking related book that money can buy. For the exam, we had to study the better part of the book and most students did flunk this course (btw I got a whopping 90%). Over the past 6 years, I’ve forgotten most things, but one of the examination questions stayed with me :

Imagine that you have trained your St. Bernard, Bernie, to carry a box of three 8mm tapes instead of a flask of brandy. (When your disk fills up, you consider that an emergency.) These tapes each contain 7 gigabytes. The dog can travel to your side, wherever you may be, at 18 km/hour. For what range of distances does Bernie have a higher data rate than a transmission line whose data rate (excluding overhead) is 150 Mbps? (Thx to Georgi’s blog for the exact phrasing).

Well, a week or so ago, one of our applications started to show some incoherent behaviour and the manufacturer asked us to upload a dump of the application’s database by FTP. No problem there, except the most business firewalls block FTP as a protocol, thus we needed intervention of the firewall team, which costs money. In addition, uploading an entire database takes 1) bandwith and 2) time and 3) someone who supervises the upload for security reasons, and thus makes uploading of a database a very costly operation.

And then the question, that has laid dormant for 6 years in my memory, bubbled to the surface and suddenly I realized what the most cost-effective way was, to send the database to the manufacturer : a box of DVDs shipped with next-day delivery and it only costs 7,50 dollars.

Bottom line of the story : never ever underestimate the bandwith of a box of DVDs.