Bandwidth of Large Airplanes

Back in the early days of this blog, I had a post on Buzzwords Galore and Bandwidth that May Rival Your Station Wagon. The topic was a “hybrid optical and packet network” being deployed by Internet2 in 2006, and in the tail end of the post text I explained the reference to the station wagon part of the post title:

When you think you have a really zippy network connection, someone will (should?) bring up an old internet adage which says “Never underestimate the bandwidth of a station wagon full of tapes.”

In the post comments, Walt Crawford asked “How about a 747 full of BluRay discs?” I must have been bored, because I calculated that bandwidth as 37Tb/s, and I even showed my work. Last week an internet citizen going by the name “Steveo” updated the table for an Airbus A38-800F. He (or she) and I arrived at different numbers (Steveo seems to have mistaken cubic feet for cubic meters in the calculation and didn’t update the maximum airspeed figure), so perhaps it is time to revisit this topic. (And while we’re at it, we’ll throw in numbers for Boeing’s latest freighter aircraft: the 747-8F.)

Boeing 747-400FBoeing 747-8, FreighterAirbus A380-800F (proposed)
Cargo capacity of aircraft, in cargo configuration, in cubic metersSource1   764Source  857.7Source  1,134
Volume of a carton of 200 slim jewel cases (53cm by 26cm by 15.5cm), in cubic meters  Source – – – – – – – – 0.021359 – – – – – – – – 
Number of cartons of slim jewel cases per aircraft35,76940,15653,092
Number of slim jewel cases, each with one Blu-ray DVD, per aircraft7,153,8008,031,20010,618,400
Data capacity of one Blu-ray DVD, dual layer, in Gigabytes  Source – – – – – – – – 50 – – – – – – – – 
Same, in Gigabits (8 bits per byte) – – – – – – – – 400 – – – – – – – – 
Data capacity of one aircraft, in the cargo configuration, filled with dual-layer Blu-ray DVDs in slim jewel cases, in gigabits2,851,520,0003,212,480,0004,247,360,000
Maximum cruising speed of aircraft, in knotsSource  507Source2  559Source3  589
Flight time between New York’s JFK airport and Los Angeles’ LAX airport at maximum cruising, in seconds4Source  16,200Source  14,760Source  14,040
Bandwidth of cargo aircraft filled to capacity with Blu-ray discs in slim jewel cases traveling at maximum rated cruising speed between John F Kennedy Intl airport and Los Angeles Intl airport, in gigabits per second176,637217,648302,519

Picture of the Main Cargo Deck of a Boeing 747-400F

Boeing 747-400F Main Cargo Deck. How many rectangular boxes can we fit in a round space?

As with the first post, this of course assumes a negligible time to load and unload said Boeing 747-400, no airport congestion, a frictionless plane and a perfect spherical earth, along with several other typical assumptions from the world of physics. It also assumes that your can fit rectangular-shaped cartons in a cargo space that is clearly curved while still maximizing space. Check my math and let me know if I made a mistake.

Now, by contrast, the latest notice I could find of high-speed data transfer over a network was a mention in December last year. In a press release from Caltech with the title “High Energy Physicists Set New Record for Network Data Transfer” is this paragraph:

The focus of the exhibit was the [High Energy Physics] team’s record-breaking demonstration of storage-to-storage data transfer over wide area networks from two racks of servers and a network switch-router on the exhibit floor [of SuperComputing 2009 in Portland, Oregon]. The high-energy physics team’s demonstration, “Moving Towards Terabit/Sec Transfers of Scientific Datasets: The LHC Challenge,” achieved a bidirectional peak throughput of 119 gigabits per second (Gbps) and a data flow of more than 110 Gbps that could be sustained indefinitely among clusters of servers on the show floor and at Caltech, Michigan, San Diego, Florida, Fermilab, Brookhaven, CERN, Brazil, Korea, and Estonia.

So, 110 Gbps from a network and 217,648 Gbps from a Boeing 747-8 Freighter. (We’re not counting yet the capacity of the theoretical Airbus A380-800F.) Only three orders of magnitude before the proverbial station wagon full of tapes is put to rest.


10-Jun-2010. If you have read this far, be sure to check out “Bandwidth of Large Airplanes, Take 2” by Walt Crawford. He takes on the points of 100-disc spindles, 2TB hard drives, and whether weight is a limiting factor in this scheme. Thanks, Walt!


  1. The original posting listed 159 as the capacity using a source that is no longer on the web. According to the Boeing site, 159 is the capacity of the lower deck, which doesn’t include the 605 cubic meters of capacity on the main deck. Go figure. []
  2. Converted from Mach to knots via Google. []
  3. “Maximum Level Speed” from specs converted from mach to knots via Google. []
  4. “Includes 15 minute bias” []

Access Management and Provisioning Technology

Building on the shoulders of others — isn’t that how that quote goes? There has been a stack of printouts on my desk for a while now for various access management and service provisioning technologies. Rather than keep the paper, I’m putting the list here so I know how to get back to them if/when I need to. (Of course, along the way if you’d like to comment on them or suggest others to look at, please feel free to do so in the comments.) Note, too, that by listing them here I’m not proposing, or even sure if, all of these pieces come together to a coherent structure.

Grouper — Internet2 Middleware

Grouper is an open source toolkit for managing groups. It is designed to function as the core element of a common infrastructure for managing group information across integrated applications and repositories. Grouper combines multiple sources of group information, both automated and manual, in managing memberships and other group information in a Group Registry, a central information asset complementary to a site’s Person Registry. Grouper manages two primary types of objects: groups and namespaces. Groups are created and named within a namespace. Group management authority can be limited ”

Now at version 0.9, Grouper is part of a suite of tools from the NSF Middleware Initiative (NMI) that supports “development, testing, and dissemination of architectures, software, and practices in the areas of identity and access management.”

Signet – Internet2 Middleware

“Core middleware services such as identity management, directory, and authentication provide a foundation for secure, manageable applications throughout an institution. Even with this foundation, as systems and applications proliferate it becomes more and more difficult to manage user access consistently and cost-effectively. [The Signet] privilege management service is a relatively new component of campus middleware that addresses this problem by providing centralized management of user privileges across a range of applications. The benefits of this service include: a standard user interface for privilege administrators; consistent, simplified policy definition, via roles and integration with core campus organizational data; improved visibility, understandability, and auditability of privilege information; and standard interfaces to other infrastructure services and to application systems to support integration.”

Now at version 1.01, released 29-Mar-2006. Could this kind of provisioning service be used to generate XACML files to drive FEDORA?

OASIS eXtensible Access Control Markup Language (XACML)

XACML is expected to address fine grained control of authorized activities, the effect of characteristics of the access requestor, the protocol over which the request is made, authorization based on classes of activities, and content introspection (i.e. authorization based on both the requestor and potentially attribute values within the target where the values of the attributes may not be known to the policy writer). XACML is also expected to suggest a policy authorization model to guide implementers of the authorization mechanism.”

Sun’s XACML Implementation (available at Sourceforge) is the access management engine embedded into the FEDORA repository.

Acegi Security System for Spring

Acegi Security is a powerful, flexible security solution for enterprise software, with a particular emphasis on applications that use Spring. Using Acegi Security provides your applications with comprehensive authentication, authorization, instance-based access control, channel security and human user detection capabilities.”

Release 1.0.0 came out in May 2006 after nearly two years of development.

Buzzwords Galore and Bandwidth that May Rival Your Stationwagon

At the recent LITA Top Technology Trends gathering, Clifford Lynch spoke of an advanced network emerging from Internet2 that is built as a hybrid between optical-switched and packet-switched networks. Today’s Internet2 Newsletter has a description of the activities, excerpted below

Internet2 and Level 3 to Deploy Next Generation Nationwide Research Network

The new Internet2 Network, a dynamic, innovative and cost-effective hybrid optical and packet network, will provide next-generation production services as well as a platform for the development of new networking ideas and techniques.

Internet2 has entered into a partnership with Level 3 Communications, a leading national telecommunications carrier, to provide the U.S. research and education community with a dynamic, innovative and cost-effective hybrid optical and packet network. An extension of the Internet2 cutting-edge tradition, the new network is designed to provide next-generation production services as well as a platform for the development of new networking ideas and techniques. Internet2 is committed to ensuring community involvement in the development, implementation, and operations of the new network.

The new Internet2 Network will be deployed nationally over 13,000 miles of dedicated fiber, providing complete community control of the optical layer and highly granular lightpath services that can be provisioned dynamically. It will provide short-term and long-term waves, as well as on-demand or advanced reservation “lightpath” scheduling. The IP network, corresponding to the current Abilene footprint, will be built on the optical network. A basic connectivity package for direct connectors is expected to include two 10 Gbps waves, one for IP and one for point-to-point optical services.

Optical (Layer 1) network characteristics:

  • Initial deployment – 10 x 10 Gbps wavelengths along network footprint
  • Maximum capacity – 80 x 10 Gbps wavelengths
  • Scalability – potential migration to 40 Gbps and 100 Gbps capabilities
  • Flexibility – support for sub-wavelength (e.g., 1 GigE) dynamic provisioning across every wave on the network backbone.

The Level 3 carrier agreement provides reliability and unprecedented community control over the networking infrastructure, without taking on the risks of equipment sparing and obsolescence as well as the burden of substantial operational responsibilities. Level 3 will be responsible for meeting a Service Level Agreement (SLA). The buildout of the network will happen over several months, with a target completion in the fall of 2007. The transition to the new network will not disrupt existing connectivity and services.

The Internet2 Networks page has a description that is a little bit more approachable:

Internet2 and Level 3 Communications, Inc. will develop and deploy a new nationwide network and new services to enhance and support the advanced needs of the academic and research community. This new network initially will offer Internet2 members 100 gigabits per second (Gbps) of capacity, more than 10 times that of the current Internet2 backbone network, and will be designed to easily scale to add capacity as Internet2 members’ requirements evolve over time. Based on input and feedback from the research and education community, including experience gained with the Hybrid Optical and Packet Infrastructure (HOPI) project, the network will be designed to support a full range of production IP services as well as new on-demand, dedicated optical wavelength services to support the most demanding network applications and experimentation.

Okay, maybe that description isn’t all that more approachable either. The thing is this: the research and development community are pushing the raw networking capabilities farther and farther. “Optical wavelength services” may not mean much to you — perhaps about as much as the intricate chemical dance that turns petroleum into gasoline, plastics, chapstick and bubble gum 1 — but the comparison is not too much of a stretch. They’ve figured out how to send multiple frequencies of light down the same piece of fibre-optic cable, effectively multiplying its capacity. The neat thing about the Internet2 work is that, should you need it, it sounds like you’ll be able to sign up for a point-to-point lightwave frequency to do with what you need. (You’ll probably need a pretty good reason, of course.)

Oh, and the stationwagon comment? When you think you have a really zippy network connection, someone will (should?) bring up an old internet adage which says “Never underestimate the bandwidth of a station wagon full of tapes.” (This, of course, shouldn’t be confused with the term “sneakernet” — the bandwidth speed and capacity at which you could walk your flash drive over to your colleague rather than trying to e-mail, FTP, torrent, webify, or send via carrier pigeon that document that the two of you have been working on.)


  1. Butyl Rubber is in Bubble Gum and you need petroleum to make butyl rubber. gack []