Coming to Grips with the Information Age
9/92 Dr. Dobb’s Journal, USA: Programmer’s Bookshelf: Coming to Grips with the Information Age, William F. (Bill) Jolitz. William Jolitz writes on the seperated evolution of the Internet apart from the world's largest connected network - the telephone system, as he reviews Global Telecommunications: Layered Networks, Layered Services by Robert Heldman.
Coming to Grips with the Information Age
Review by William F. Jolitz
Copyright (C) Dr. Dobb's Journal, September, 1992
During the mid-1970s, computer enthusiasts were frequently as knowledgeable
about the telephone system and telecommunications as they were about the
details of their microprocessors. In fact, the details of telephone switching
systems, cross-bar mechanisms, signaling, and other matters were common
topics of discussion at Homebrew Computer Club meetings. (I remember once
being accosted during "random access" by a rather famous fellow
waving schematics related to an ESS switch!) Still, it's surprising that
computer and telecommunications technologies continue to be viewed as immiscible
disciplines, especially when you consider that they face many of the same
problems and that their histories are so intertwined.
During the '70s, the architects of the Internet felt quite safe keeping
the address space at a mere 32-bit size, never imagining this might be consumed
before the end of the century. But the unanticipated and tremendous growth
in computer networking in the '80s changed this. We now use large numbers
of interacting computer systems, so that computer networking forms the basis
of a modern information infrastructure. It's disquieting, though, that this
revolution in information exchange has occurred removed from the world's
largest connected network--the telephone system.
In Global Telecommunications: Layered Networks, Layered Services,
Robert Heldman seeks to outline his vision for the integration of these
two worlds from the telecommunications industry perspective. While the book
fails in its stated goal of showing you how to take advantage of communications
technology (a daunting task for any single book), it does provide what may
be a more valuable service: Global Telecommunications lays bare the
frustrations of bringing about the birth of this global information industry.
In a rambling style, the author leads us through the process by which the
telecom industry structures the problem of a unified voice, video, and data-communications
network. That the book is targeted at the telecommunications industry is
apparent in its use of telecom terminology and approaches, and its attempts
to span the gulf between the nuts-and-bolts physical realities and the top-down
market-driven business analysis of a telecommunications corporate participant.
This approach normally would be guaranteed to annoy both the dyed-in-the-wool
computer user and the telecommunications professional. Computer professionals
quickly become frustrated at being sold a "multimedia soon" future
which requires megabit (perhaps gigabit) service, while having to put up
with current piddling kilobit-per-second analog modem communications. On
the other hand, any astute telecommunications professional is already aware
of the difficulty of implementing even the most mundane of ideas presented
in this book. However, even though it oscillates between microscopic details
(bit-density problems with T1) and cosmic issues (Maslow's Hierarchy of
Needs), Global Telecommunications provides us with a unique view,
a "gestalt" if you will, of an industry at the crossroads. In
fact, after a while I began to feel that I was reading a psychoanalytic
profile of the telecommunications industry in crisis. It underscored how
difficult it will be for the industry to take full advantage of the new
For example, the book's perspective on data-communications networking (page
123) is quite revealing: "We are expanding from the traditional analog
voice-based network, with voice-only services...we are beginning to use
digital capabilities to better operate and expand the network." In
essence, data is viewed as a special case of voice! This isn't really surprising,
since that's what the telecommunications industry made its fortune on. However,
this is exactly opposed to the computer industry's approach, where digital
information is everything. Every media--voice, data, video--is digital.
Another example of the book's somewhat myopic view can be found in its treatment
of ISDN. Like fusion, ISDN has been "just around the corner" for
at least a decade. While its genesis occurred at about the same time the
first PCs appeared, it's been slow going for ISDN ever since. The problem
is that the telcos don't view ISDN as an extension of LANs, but as a replacement
for them (pages 147-148).
By delaying the public network offering in the 1970s and 1980s, the RBOCs
[regional Bell Operating Companies] have driven the MIS managers of large
firms to create new networks that are quite autonomous from the telcos....
This lack of success encouraged considerable growth of point-to-point LAN-type
architectures.... This has resulted in a separate "private networking"
approach to interconnect LANs by gateways, bridges and routers. However,
expansive growth has made this cumbersome, quite expensive and somewhat
limited to closed user groups. In the new world of multiple systems interfacing
together, there is a need for the more robust public networks to carry this
traffic to and from the internal private networks.
In fact, LANs have been fantastically successful, partially due to their
relatively low cost and availability, and partially to their appropriateness
in treating data like data, not a special case of voice. It's ludicrous
to believe that ISDN will recapture the bandwidth lost to private data networks
over the next decade without examining issues such as performance requirements
and existing software interfaces.
However, as pointed out in Global Telecommunications, digital communications
still amount to only 3 percent of the total current service present, so
you can expect voice to be in the driver's seat over the long term (the
next 40 years?) as the industry develops new equipment plans. Quite simply,
until the telcos see an economic necessity, they will not take data seriously.
(Given the rapid rate of change in this area, they could end up missing
the boat completely.)
A point not addressed in Heldman's book is "why" the telephone
system went digital in the first place. Steve Hardwick shows in ISDN Design
that it was the economics of digital transmission, switching, and signaling
that caused the industry to migrate incrementally away from ancient analog
mechanisms. This has had the indirect result of tossing the entire telecommunications
industry into the information market, since now voice is just one of many
kinds of information to be transmitted. This was not anticipated, but rather
dictated by circumstance.
In a computer-oriented world, where entire computer systems become obsolete
after a few years, there's little patience for ISDN, even though it fundamentally
extends the reach of computer technology to any point in the world and has
the potential for turning every telephone into a computer system. Compared
to the computer industry's hare, the conservative, button-down telecommunications
industry begins to look like a tortoise by always attempting to justify
each step before making it. The irony of this is that to be in the "information
side" of the business, you must be immersed in the application of information.
Unfortunately, the monolithic firms capable of orchestrating gigantic phone
networks cannot seem to grasp this simple fact.
Global Telecommunications is valuable for its isolated vignettes
focusing on the needs of the telecommunications customer as well as outlining
(sometimes futile) attempts to provide what the customer desired. It is
worthwhile to compare this approach with the breakneck pace of high-speed
computer networking (like you find within the Internet community). Of marked
contrast is the mind-boggling complexity of the low level of abstraction
present in telecommunications (mostly at the ISO physical and link layers)
versus the relatively trivial components in most computer-networking fields.
(I used to have an entire bookshelf dedicated just to a partial description
of ISDN, while a single book on TCP/IP was sufficient.) It is this holdover
from the past that forces the tortoise carrying the world on its back to
pale beside the lightweight hare that uses abstraction to minimize burdens.
The tortoise has a problem in scaling down; the hare has a similar problem
in scaling up. One measures time in decades, while the other is unwilling
to wait for a fraction of a year for fear of missing a technology window.
Global Telecommunications' unstructured "all over the map"
approach is its worst characteristic. You just can't read it in a typically
linear fashion and expect to keep a logical train of thought. Another irritation
is the frequent mention of market-driven customer-application approaches
that are completely naive regarding digital-communications applications.
(There is no mention, for example, of remote file systems, distributed computing,
or interoperability.) In this, the hallmarks of modern computer-networking
progress of recent years are completely ignored. Alas, this is a major omission
in an industry that prides itself on its technical competence and thoroughness.
Telecommunications is rapidly approaching a crossroads. Recent court and
regulatory decisions mean that other firms can access telephone subscribers
directly, as an alternative to local exchange carriers (LECs). Many powerful
interests are already jockeying for position to compete with them on an
equal basis to provide even more services than the existing LECs provide.
Global Telecommunications correctly puts forth a number of barriers for
the industry to hurdle, but it misses the most significant one: employing
the existing computer networking technology to accelerate the demand and
acceptance of modern communications technologies. In other words, the compelling
need for new communications technology is rooted in developing the existing
information-system paradigm, not in trying to invent something totally new
or recast things in a past image.
There may be some historical significance to Global Telecommunications
in that it captures a moment in time before the pent-up innovation of one
industry impacts another, very much like the old saw of an irresistible
force meeting an immovable object. I'm sure it will be an interesting sight,
regardless of the outcome.
Global Telecommunications: Layered Networks, Layered Services
Robert K. Heldman
390 pages, $39.95
Academic Press, 1989
152 pages, $34.95