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The information presented is somewhat dated, but fascinating none the less. -Editor

Does transferring a terabyte of data via sneakernet make sense? First, consider the bandwidth capabilities and monthly cost of  a few common Internet connections.

                                Cost            Download rate  Upload rate
                               (month)       per second         per second

56.6 Modem             $15                5 KB                    4 KB

DSL                           $30            192 KB                  24 KB

DSL,Premium           $50            384 KB                   48 KB

Cable                       $50            300 KB                   30 KB

Cable,Premium       $80             600 KB                   60 KB

T1                           $300           192 KB                  192 KB

T3                           $1,400        5.4 MB                  5.4 MB

OC-3                      $7,500         19 MB                   19 MB

Of course, costs may vary; I chose costs that jibed with my personal experience and lined up with a few cursory searches for pricing around the web. Please let me know you think these costs are way out of line. Assuming for the sake of argument that these are representative costs and throughput rates, how much would it cost to transfer, let's say, a 20 gigabyte HD-DVD file?

                                Download 20 GB                               Upload 20 GB

56.6 Modem            49 days  $24.27                                 61 days $30.34 

DSL                         1? days  $1.26                                 10 days $10.11

DSL,Premium         15 hours $1.05                                   5 days  $8.43

Cable                     19 hours $1.35                                   8 days  $13.48

Cable,Premium      10 hours $1.08                                  4 days  $10.79

T1                          1? days  $12.64                                1? days $12.64

T3                          1 hour   $1.98                                    1 hour  $1.98

OC-3                      17 mins  $3.05                                  17 mins $3.05

And how much could we upload or download in total, assuming we had these connections going full-bore, around the clock?

                                in 24 hours                                       in 1 month

                                Download Upload                            Download Upload

56.6 Modem            422 MB   338 MB                               12 GB    10 GB

DSL                         16 GB    2 GB                                     475 GB   59 GB

DSL,Premium          32 GB    4 GB                                    949 GB   119 GB

Cable                     25 GB    2 GB                                     741 GB   74 GB

Cable,Premium      49 GB    5 GB                                     1.5 TB   148 GB

T1                          16 GB    16 GB                                   475 GB   475 GB

T3                          472 GB   472 GB                                14 TB    14 TB

OC-3                      1.6 TB   1.6 TB                                  49 TB    49 TB

Let's say we wanted to send a terabyte of data via sneakernet:

* Two 500 GB hard drives weigh about five pounds; we can wrap the drives in bubble wrap and fit them in a standard FedEx box.

* It costs about $60 to send five pounds in a standard FedEx box coast-to-coast in 24 hours.

* The total transit time is 32 hours: 24 hours, plus 8 hours to copy the data on and off the drives.

We just transferred data at the rate of 9.1 megabytes per second. The only internet connection that's capable of our sneakernet throughput level is the OC-3. None of the others are even close, particularly if you consider the highly asymmetric nature of consumer connections, where upload rate is a fraction of the download rate.

And what about the cost? Not including the $300 expense of the two hard drives (which I think is fair, because they're reusable), the total cost per gigabyte breaks down like so:

                                Cost per GB        Cost per GB

                                Downloaded      Uploaded

56.6 Modem            $1.21                     $1.52

DSL                         $0.06                     $0.51

DSL,Premium         $0.05                     $0.42

Cable                     $0.07                     $0.67

Cable,Premium      $0.05                     $0.54

T1                           $0.63                     $0.63

T3                           $0.10                     $0.10

OC-3                      $0.15                     $0.15

Sneakernet            $0.06                     $0.06

It wasn't obvious to me, but the sneakernet math clearly works. This is exactly the kind of insight Jim Gray was famous for.

Jim also says the cost of internet bandwidth was roughly a dollar a gigabyte for Microsoft in 2003. Is that still how much internet bandwidth costs today? According to the figures I found, the only connection that expensive today is a modem. And who uses modems any more? It seems implausible that consumer internet bandwidth would be sold cheaper than large blocks of commercial internet bandwidth. Let's take a look.

* Amazon's S3 service charges 20 cents per gigabye to transfer data.

* Robert X Cringely regularly gets charged 20 cents per gigabyte for NerdTV, and guesses that large bandwidth consumers like YouTube can negotiate rates as low as 10 cents per gigabyte.

* Mitch Ratcliffe did a survey of internet providers and found that most charge 85 cents per gigabyte, and he proposes YouTube could negotiate a rate of 45 cents per gigabyte.

I'm not sure who to believe. It's a good sign that most estimates are under the $1.00 per gigabyte rate that Jim quoted in 2003. I'd like to think that the cost of internet bandwidth is getting less expensive over time. High bandwidth costs lead to a de-facto "popularity tax", and that's like a giant wet blanket over content creators. Cheaper bandwidth is a net public good: it leads directly to more content, and higher quality content, for everyone.

Originally published at http://geekswithblogs.net/mikedopp/archive/2008/01/24/bandwidth-costs-and-time-for-sneakernet.aspx