SMART Letter #73
Buy as Many Nines as You Need
June 26, 2002

             SMART Letter #73 -- June 26, 2002
            Copyright 2002 by David S. Isenberg
   -- "single point of success" -- -- 1-888-isen-com

>  Buy as Many Nines as You Need
>  More on Cisco and Corporate Culture
>  SMART People save $2000 at WTN Summit
>  Motorola Launches Canopy
>  Quote of Note: Billy Tauzin
>  Copyright Notice, Administrivia

Buy as Many Nines as You Need
   by David S. Isenberg  

Two recent articles in Business Communications Review (BCR) 
on the concept of five-nines (99.999 percent reliability) 
in circuit and packet networks miss one key fact: To the 
extent that true competition is available, customers can 
buy as much network reliability as they are willing to pay 
for (see David Yedwab and Chris Talbott's article in BCR, 
June 2002, pp. 46-52, and Gary Audin's article in May 2002, 
pp. 22-27).

The only certain path to reliability is physical redundancy 
-- the use of multiple independent networks with dissimilar 
infrastructures in different places.  A network with the 
same brand of router everywhere is subject to single-point 
failures of hardware or software.  So are facilities that 
share the same route or the same building.  Design for 
reliability is design for multiple, heterogeneous networks.

The definitive tome, Engineering and Operations in the Bell 
System, (R.F. Rey, ed., Bell Labs, Murray Hill NJ, 1977), 
which sat on the shelf of every Bell Labs engineer in the 
Bell System's heyday, devoted but two paragraphs to 
physical redundancy.  It declared that network designers 
faced, "two fundamentally conflicting goals: to minimize 
the total cost of the network and to provide redundancy as 
a protection against major service interruptions."  It 
continued, "Redundancy is provided by multiple, physically 
separate long-haul routes, although at increased cost."  
That was the last word.  To Engineering and Operations, 
reliability was more an economic issue than a technical 

A Buyer's Market
In the bad old days, the extra costs of redundancy were 
folded into the monopoly's rate base, and the customer had 
no choice.  Any color, as long as it's black.  

Today, competition exists.  Customers, especially business 
customers, can buy connectivity in a variety of forms -- 
copper, fiber, wireless, etc. -- from several different 
providers.  Each provider wants their service to be 
reliable, but the survival imperative is low cost -- 
everybody wants to be the low-cost provider.  

This creates a buyer's market for reliability.  If one 
network is not reliable enough, buy connectivity from two.  
After all, competition makes network services inexpensive, 
and customers can buy boxes that will fail-over gracefully.  
If the probability of an outage in either network is 1%, 
the probability that a customer with two one-percent 
networks will be without service is 0.01%  That's four 
nines of up-time.  Still not enough nines?  Buy service 
from a third provider.  

Sure extra reliability costs more -- it always has, and it 
always will.  But today the trade-off is explicit, and it 
is in the hands of the customer.  

Speaking for myself, the fact that I have cable modem 
service, dial-up Internet access and "wireless web" on my 
cell phone practically means that I'll *never* be without 
an Internet connection.  Of course I pay for each increment 
of reliability, but I'd rather have the choice than have to 
buy my reliability as part of a hairball of hidden features 
sold by a single provider.  

A Broader View
Both the BCR articles referenced above take too narrow a 
view of reliability differences between IP and TDM 
networks.  It is like trying to compare the flying 
abilities of bumble bees and 747s.  Not only are there vast 
differences (and a single similarity), but it is much 
easier to prove that a TDM network is reliable and that a 
747 can fly.

A TDM circuit is a definite entity.  It is made or broken.  
Its latency is built into its structure.  If it is up for 
99 minutes and down for one, you can measure the 
probability of an outage.

But IP fudges the distinction between "working" and 
"broken".  An IP network is designed to perform over 
unreliable physical media in the first place.  When a 
packet does not arrive intact the first time, and then TCP 
does its job just fine and the packet arrives on the second 
attempt, is the network broken?  When packet jitter begins 
to rise, when does the nine-counter begin to decrement?  
When can it be said that the effort to deliver a packet is 
less than "best effort"?

Admittedly, sometimes the Internet breaks.  Sometimes I 
can't dial in.  Sometimes I can't get mail from the POP 
server.  Sometimes my cable modem won't bring me the New 
York Times.  But I can stash my mail in two places.  I can 
dial in when the cable fails.  And I can always read the 
Washington Post.  I have never yet seen a failure that a 
smart customer can't overcome.  There are material costs of 
administering reliability like this, but these costs, too, 
are explicit and under customer control.

Just as the Internet pushes value creation to the edge of 
the network by treating any feature that is integral to a 
specific set of facilities as just another network-specific 
difference to route around, so does the Internet push the 
ultimate responsibility for reliability into the lap of the 

[This article originally appeared in Business 
Communications Review, June 2002, p. 53, reprinted by 
permission of Key3Media, the publisher of BCR.]

More on Cisco and Corporate Culture

I was gratified to see that "The New Cisco Kid -- SMART 
Letter #73" stirred up the beehive at Cisco.  I got at 
least 15 new Cisco-employed subscribers.  

One of them, who requested that his or her name not be 
used, nailed the patrimonial bureaucracy syndrome when he 
or she wrote: 

  "I see a couple of things that have happened in the last 
   four years or so compared to how we were in the early 

  "1. people are more concerned about the past, present, 
   and potential emotional states of VP's instead of what's 
   right. A kind strange kind of "VP potential emotional 
   state" poker gets played in meetings:
      "John is really excited about plan A"
      "Larry has a lot of heartburn about doing plan B"
      "I don't think Bill would like to see plan A happen"
      "I don't want to be the one to tell Kevin we can't 
       make A happen"
   [There seems to be little consideration of] the relative 
   risks and merits of the options.  [Instead] bargaining 
   is based on various VP's emotional reaction to the 
   results of the meeting.

  "2. Individuals cannot take action or make suggestions: 
   you have to be following orders from a VP or relaying 
   his desires."

Now consider this passage from Moral Mazes (Robert Jackall, 
Oxford, New York, 1988), the best objective study of 
corporate culture and the origin of the term "patrimonial 

  "When managers describe their work to an outsider, they 
   almost always first say: 'I work for [Bill James]' or 'I 
   report to [Harry Mills].' and only then proceed to 
   describe their actual work functions . . . The key 
   interlocking mechanism of [modern corporate culture] is 
   its reporting system.  Each manager . . . formulates his 
   commitments to his boss; this boss takes these 
   commitments and those of his other subordinates, and in 
   turn makes a commitment to his boss . . . This 
   'management-by-objective' system, as it is usually 
   called, creates a chain of commitments from the CEO down 
   to the lowliest product manager or account executive.  
   In practice, it also shapes a patrimonial authority 
   arrangement that is crucial to defining both the 
   immediate experiences and the long-run career chances of 
   individual managers.  In this world, a subordinate owes 
   fealty principally to his immediate boss."

Moral Mazes goes on to describe how bosses use ambiguity 
with their subordinates (and other more-or-less unconscious 
subterfuges) in order to preserve the power to claim credit 
and deflect blame, which tends to perpetuate the 
personalization of authority.  Unlike a straight, Max Weber 
style bureaucracy, which is procedure-bound and rule-
driven, a patrimonial bureaucracy is a set of hierarchical 
fiefdoms defined by personal power and patronage.  

You can read my review of Moral Mazes in "Corporate 
Culture's Twisty Passages -- SMART Letter #22" at


SMART People Save $2000 at World Technology Network Summit

The WTN Summit and Awards will be held July 21 and 22 in 
New York City.  SMART People who REGISTER BEFORE JULY 1 
will pay $1950 (normal fee is $3950).  After July 1, the 
SMART People's rate is $2750 (versus $6750).  Last year's 
WTN meetings in London were excellent! 

For the special SMART Person's rate, see:

Motorola's Canopy comes out from under

Motorola has just launched a wireless, unlicensed (5GHz) 
last-mile product line named Canopy that delivers up to 10 
megabits per second per subscriber, for up to 1200 
subscribers per access point, for a one-time cost that 
asymptotes at around $500 list.  Note that Canopy is not 
Cognitive Radio -- it is just good solid wireless 
connectivity with a keep-it-simple-stupid proprietary 
modulation method.  I used an early version last year.  We 
set up a 1/3 mile link with ease and it worked flawlessly 
for the three days we needed it.  My friends at Motorola 
are aiming at the Wireless ISP market, and it looks like 
they might have hit it -- see 

Quote of Note: Billy Tauzin

  "I don't want our military operations to be interfered 
   with, and I don't want planes to fall out of the sky. 
   But I want real-world evidence that tells us whether 
   ultrawideband devices, on a stand-alone or cumulative 
   basis, would cause these things to occur."
U.S. Rep. Billy Tauzin (D-La.),


July 21-22, 2002, New York.  World Technology Network Summit 
and Awards.  For a SMART Person's discount, see

October 8-10, 2002, Atlanta GA.  Fall VON.  I'll be giving 
an Industry Perspective talk.  Time and date to be 
determined.  See

October 15-17, 2002, New Orleans LA.  Fiber to the Home 
Council Annual Conference.  I'll be giving a keynote (on why 
neither telco nor cable TV co will bring us fiber to the 
home).  Nothing on the website yet, but keep checking for information.

COPYRIGHT NOTICE: Redistribution of this document, or any 
part of it, is permitted for non-commercial purposes, 
provided that the two lines below are reproduced with it: 
Copyright 2002 by David S. Isenberg -- -- 1-888-isen-com