
at ICA available for use for the e-mail connection. It
was hoped that the China-Germany e-mail connection
would be a step toward connecting China with the
growing CSNET
6
, a network begun in the U.S. in
1980 to provide e-mail connections among university
computer science departments. To connect to CSNET,
a computer would need particular communication
functionality as part of its operating system. The
specifications or protocols describing that functional-
ity for CSNET were the CSNET/PMDF transport
protocols. This PMDF had not yet been implemented
in the Siemens BS2000 operating system. In late
1984, Zorn decided to undertake this task together
with his students but only as a background job.
Including the lower levels, it took at least two years to
complete. The work was financially supported after
November 1985 by the government of the West
German state of Baden-Wuerttemberg, under Prime
Minister Lothar Spaeth.
CSNET e-mail traffic to and from Germany was
routed using the X.25 lower level protocols. The X.25
protocols were the result of an effort to create a
universal and global packet-switched network on
what was then the bit-error prone analog telephone
system. Much of the X.25 system is a description of
the rigorous error correction needed to achieve this.
7
In 1985, there was no physical path to carry X.25 e-
mail traffic between China and Germany. To have
such a path, telephone lines with switches that could
route X.25 e-mail traffic were needed. China had
begun to develop a network of such switches for
internal X.25. So had Germany. X.25 e-mail traffic
could be transported within China and within Ger-
many. But there was no X.25 link between them.
With the help of the PKTELCOM data network
administered by the Beijing Telecommunications
Administration, the Karlsruhe team made contact with
the Italian carrier Italcable which had some leased
lines between China and Italy. Italcable agreed to
open its switches to route the anticipated X.25 e-mail
traffic between China and Germany. Italcable was
able to open its switches on Aug. 26 1986. From that
day on, reliable remote computer-to-computer dia-
logue was available between Karlsruhe University
and ICA through PKTELCOM. This channel would
make possible the communication necessary one year
later during the implementation phase of the China-
Germany e-mail connection. Also, as soon as the
computer scientists at ICA and Karlsruhe could
implement X.25, PMDF, and other protocols on the
Siemens BS2000 computer at ICA in Beijing, the
China-Germany connection would have an X.25
route through Italy.
In late summer 1987, Zorn was in Beijing for
the third CASCO conference where he gave the
keynote address on “Computer Networks”. But also
he was there to work with the staff of the ICA to set
up the first e-mail connectivity between China and
Germany. His team at Karlsruhe University had
succeeded in getting the PMDF protocols to work on
their Siemens BS2000 computer. In a little over two
weeks, September 4 to 20, 1987, assisted by the staff
of ICA, Zorn with his team implemented within the
operating system of the ICA Siemens 7760/BS2000
computer the necessary protocols and installed the
necessary communications equipment to make
possible e-mail connectivity with Karlsruhe. For the
lower three OSI layers, X.25 with PAD
8
access over
telephone lines were used. For the higher layers, the
Karlsruhe BS2000/PMDF implementation of the
CSNET protocols was used. On September 14, 1987,
Professor Zorn and the ICA staff achieved the
breakthrough they needed, host-to-host connectivity
with Karlsruhe University. Zorn was able then to
leave half of his team in Beijing to work with their
Chinese colleagues to finish the job.
Before Zorn left, the joint German and Chinese
team composed an e-mail message with the subject
line, "First Electronic Mail from China to Germany".
The message began in German and English, “Ueber
die Grosse Mauer erreichen wie alle Ecken der Welt”
"Across the Great Wall we can reach every corner in
the world." The message, with cc:s to Lawrence
Landweber, David Farber, Dennis Jennings, and to
themselves was signed by Professor Werner Zorn for
the University of Karlsruhe Computer Science
Department (Informatik Rechnerabteilung) and
Professor Wang Yuen Fung for the ICA. Eleven
coworkers are also listed as signatories, Michael
Finken, Stefan Paulisch, Michael Rotert, Gerhard
Wacker and Hans Lackner on the Karlsruhe side and
Dr. Li Cheng Chiung, Qiu Lei Nan, Ruan Ren
Cheng, Wei Bao Xian, Zhu Jiang and Zhao Li Hua
on the ICA side, suggesting the complexity of the
task. Zorn mentioned Dr. Li Cheng Chiung, in
particular, as playing an important role as the Direc-
tor of the ICA Computing Center. Successful con-
nectivity was achieved in a few more days. On
September 20, 1987, the first e-mail message, the
one composed on September 14, could actually be
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