Turning the Postal System into a Generic Digital Communication Mechanism

Abstract:

Recent studies find that as the adoption
rates of the Internet and broadband connections slow down in the U.S.,
the ``digital divide'' could be solidifying: those with modest
incomes, rural residents, and minorities are among those who lag
behind in Internet access. Most people living in developing regions,
who represent an overwhelming majority of the world's population, also
largely fall on the ``wrong'' side of the digital divide and are
missing out on many important opportunities that the digital world has
to offer.

Bridging this digital divide, especially by attempting to increase the
accessibility of broadband connectivity, can be very challenging. The
improvement of wide-area Internet bandwidth is constrained by factors
such as how quickly we can dig ditches to bury fibers in the ground.
The cost of furnishing ``last-mile'' wiring can be prohibitively high,
and the progress has been excruciatingly slow.

In this proposal, we explore the use of digital storage media (such as
DVDs or even hard disks) transported by the postal system as a general
digital communication mechanism. While the idea of sending digital
content via the postal system is not a new idea -- companies (such as
AOL.com and netflix.com) have used this approach to deliver software
and movies on a large scale for some time -- none of these existing
attempts have turned storage devices delivered by the postal system
into a generic communication channel that can cater to a wide array of
applications. We shall call such a system a Postmanet.

Compared to traditional wide-area connectivity options, the Postmanet
has several important advantages. These include wider reach, greater
bandwidth potential, low cost, and better scalability. In terms of
reach, the postal system is a truly global ``network'' that reaches a
far greater percentage of the world's human population. In terms of
its bandwidth, the Postmanet advantage stems from fundamental
technology trends: the explosive growth of storage technology density
implies that the amount of information that can fit into a fixed
amount of volume, or the amount of information that can be shipped by
the postal system for a fixed cost, increases exponentially at roughly
the same rate, a rate that the wide-area Internet bandwidth growth is
unlikely to be able to keep up with. Indeed, far from being a
temporary fluke, the bandwidth gap between the Internet and the
Postmanet is likely to widen as the storage density continues its
rapid improvement.

We would like to use the
Postmanet to extend and complement the existing Internet to support a
wide array of bandwidth-intensive applications. These may include
email with large attachments, web pointing to or embedded with large
data objects, remote file system mirroring for sharing and/or backup,
peer-to-peer file sharing, video ``almost on-demand,''
publish/subscribe systems for other types of content, and distance
learning.

At a first glance, it may appear deceptively simple for an end user to
manually burn and ship DVDs for whatever applications he desires. But
with many applications, hundreds of communicating parties, and
thousands of ``messages,'' for example, manual management would become
infeasible. Therefore, systematic transparency support at the levels
of network transport, programming models, routing, and applications is
necessary. We shall see two recurring themes at these different
levels of the system. One is the simultaneous exploitation of the
low-latency low-bandwidth Internet and the high-latency high-bandwidth
Postmanet so we can combine their latency and bandwidth advantages.
The other is the exploitation of the abundant capacity and bandwidth
of the Postmanet to improve its latency, reliability, and cost.