Introduction

this is not a high-tech talk
way fewer acronyms than in mots of my other talks
I didn’t invent any of the technologies covered
I didn’t write any of the software covered
Just a mere user and operator/sysadming
.. this is the world I grew up in (age 11 onwards)
very limited information available in literature and on the WWW
lots of younger members of our community lack this history

Circuit Switched Telephony

Telephony from 1876 until ~ 1988
Analog voice circuit 300-3000 Hz
Dial-up connection between A and B party
Copper wires physically switched at intermediate telephone exchange
Voice signal possibly amplified in the path

Hardware

Telephone
Copper wire[s]
Telephone Exchange[s]

images/pots_fig10.2.png

Phone Charges

In Germany during the 80ies and 90ies

even local calls were metered / charged
flat rates didn’t exist
various zones between local and long distance
not many people could afford long distance BBSing

Acoustic Coupler

First devices to transmit bits as audible tones over telephone
User manually dialled phone number like voice call
After call was established, both sides put receiver into coupler

images/accoustic_coupler.jpg

Modems

Automation of the acoustic coupler

Avoid air gap speaker/microphone path
directly generate/receive tones on phone line
directly dial the phone number / answer the line

images/analogm.png

Modems

images/Modems.jpg

Modem Speeds / Standards

Standard	Rate (bps)	Year created
V.21	300	1962*
V.22	1200	1980*
V.22bis	2400	1984*
V.32	9600	1984*
V.32bis	14400	1991
V.32ter	19200	1993
V.34	28000	1994
V.34bis	33600	1996
V.90	56000	1998

BBSs

What’s a BBS?

Computer with Modem accepting incoming calls
offering interactive service to users who dial in

To operate a BBS, you had to have

a separate/dedicated computer
- most BBS software predated/predates multi-tasking OSs
running 24/7
attached to separate / dedicated phone line

To use a BBS, you

power your computer when using it
can share your regular phone line with the modem

Content

bulletin boards / message boards
live chat with sysop (or other users in multi-line BBS)
multi-user games (text based!)
file areas / downloads
ASCII / ANSI artwork

images/dosbox-telemate-login.png

Technology/Software

Both sides: Computer + Modem
BBS Side Software
- BBS Software
- often extended by "doors" (external programs, think of CGI in Web)
User Side Software
- Terminal Program (e.g. TELIX, Telemate for DOS)

images/telemate.jpg

Demo

Time for a demo

Note	I’m using telnet instead of modem/dialup (POTS lines hard to find these days)

The "BBS Protocol Stack"

In the spirit of protocol stack diagrams…

images/bbs-protocol_stack.svg

Curiosity: Vector Graphics

BBSs were typically all Text, mostly ANSI CP437 charset
RIP (Remote Imaging Protocol) / RIPscrip introduced vector graphics
- RIPscrip introduced in 1992 (by TeleGrafix)
  - Commands like “!|w00001B0M10” to draw vector graphics over Modem
- RIPterm as terminal program for EGA (640x350)

images/Nouveau.png

Isolated BBSs

To participate in bulletin/message boards

Users log in at different times
BBS is busy while a user is logged in
Multiple modems / phone lines is one (expensive) option to scale
Time limit per User (minutes/day) often used

Points / Offline Messages

Users don’t read/write interactively during active modem call
Messages get written offline and compressed/batched during short call

Advantages:

lower cost (shorter phone calls, metered!)
shorter connection per user
BBS can scale to more users this way

images/xpmenu.gif

BBS networks (store + forward)

As opposed to individual BBSs with isolated communities…

Idea: Replicate bulletin / message boards between independent BBSs, for

scalability in number of users
scalability in geographic scope
- most users will prefer least-expensive local calls to long-distance
efficient transport over long distance due to routing/forwarding of compressed batches

BBS network technology (examples)

FIDO (Netmail + Echomail)
- Othernets like TrekNet, GerNet using same FTN technology
Z-Netz (Mail + News)
- T-Netz, CL-Netz
UUCP (Usenet Mail + News)
- Often only way to access "Internet" before IP access was available
MausNet - Münster Apple User Service
- used by up to 120 BBSs in DE / AT / CH

Example: FIDOnet

Starts in 1984 with two BBSs
Initial technological limit of 250 nodes reached in 1985
Hierarchic, Regional routing/Addressing introduced in 1986
- Nodelist defines all nodes of the network + hierarchy
Addresses like Harald Welte @ 2:2490/1343
Up to 39,000 nodes in 1996, estimated 2 Million users world-wide

Example: Z-Netz

Started as Zerberus-Netz implemented in Zerberus Software
Later renamed to Z-Netz as the ZConnect protocol was implemented in other software
- Standards defined based on perceived complexity of RFCs and Usenet/UUCP
CrossPoint (DOS) most popular point software for ZConnect
Addresses like H.WELTE@SILVER, later H.WELTE@SILVER.zer

Example: UseNet

Established in 1980 in the US
Uses UUCP (Unix-to-Unix-Copy) as transport mechanism over Modems
- UUCP was created in the 1970ies and used to copy files, including Internet Mail
Usenet News format (RFC850) designed very similar to Internet Mail (RFC822)
Hierarchy of News Groups that gets replicated / flooded across the network, e.g.
- comp.* — Discussion of computer-related topics like “comp.lang.c++”
- sci.* — Discussion of scientific subjects
Routing defined in route maps

Curiosity: Floppy Poll/Point

Not everyone had a phone line in the 1990ies
- particularly Eastern Germany had big lack of phone lines
Some people thus exchanged daily floppies in envelopes and mailed them as postal letters
Messages arrived about one day later, but with 1-2 days latency even inside the dial-up store-and-forward network, it hardly matters

images/floppy-disk-1219954_640.png

Internet

Early ways to access Internet:

Mail/News via UUCP (as stated earlier)
Dial-Up Modem to a TTY of a Unix machine connected to TCP/IP
- Often workstations at universities. You could then run FTP, IRC, telnet, Gopher on the test console
ftp-mailers
- a FTP client running on a remote machine, whose input/output is used by e-mail
- you send a mail with "ftp ftp.sun.com" and "ls"
- hours or days later you get the list of files
- you respond with cd / get / …
- hours later you get the file as batch of UUencoded mails

Internet with SLIP

if you had dial-up access to a Unix box
you could run SLIP on both sides, transporting IP over the modem line
- Result: IP. At home. In your apartment !!1!
later superseded by PPP (auto-configuration, authentication, compression, …)

Popular software stack looked like:

Windows 3.11 + Trumpet Winsock (Windows didn’t have TCP/IP!)
NCSA Mosaic as web-1.0 browser (1993 onwards)

images/mosaic.jpg

Internet on PCs before Linux

if you didn’t have a 386 or if Linux didn’t exist yet
there was KA9Q NOS
- Implementation of TCP/IP, SLIP, PPP for CP/M and DOS
- POP3 + SMTP server + client, IP routing, telnet, ARP, etc.
you could run SLIP on both sides, transporting IP over the modem line
- Result: IP. At home. In your apartment !!1!
later superseded by PPP (auto-configuration, authentication, compression, …)

ISDN

Digital Circuit-Switched Telephony Network
- Transport of Digital Voice (PCM) audio and transparent digital data
Germany
- 1989 put in operation
- Until 1993 German 1TR6 system
- From 1994 European E-DSS1
- Hugely popularized from 1995 by subsidies

ISDN Terminal Adapter

ISDN is an all-digital network
No modulator / demodulator required
Instead, so-called terminal adapter
Speeds: 64000 (single B-channel) or 128000 (both B-channels)
V.110 as adaptation to do async serial over sync ISDN (1988)

images/isdn.jpg

How to get Internet Access?

Hard to access in early/mid 1990ies outside of academia
Almost no commercial ISPs (XLink, EUnet) - and very expensive
Grass-Roots groups of enthusiasts established themselves
Kommunikationsnetz Franken e.V. (KNF, “franken.de”) one of them
- dial-up UUCP and shortly later IP for personal, non-commercial users
- POPs in Nürnberg, Fürth, Erlangen, Forchheim, Würzburg, Regensburg, …
- Every user got 6 static IP addresses routed to wherever he dialed in (OSPF!)
- served ~ 800 users / members at peak

Individual Network (IN) e.V.

Umbrella Association established in 1992
- Goal to help regional member associations with negotiating framework contracts
- Actual technical access via WiN/DFN, XLink, EUnet
- Regional Member Associations include Oche, Augusta, Escape, IN-Berlin, Hanse, INKA, Toppoint, muc.de, IN-Passau, ThurNet, MAUS, CL-Net and many more
- IN members served more than 300,000 users at one point
- Dissolved in 2000, when
  - commercial ISPs were widespread, and
  - remaining IN member organizations could get decent connectivity with IN e.V.

Internet

With packet-switched TCP-IP

you just needed to dial one number
and then access systems world-wide

This brought new purpose to leased lines

Analog Leased Lines

Telephone operator permanently interconnects wires at exchange
No signaling (dial tone, ring tone etc)
Requires modems with special capabilities
- ATA without an incoming ring first
- ATD without a dial tone first
In Germany: "Analog G" of Post/Telekom
- I finally could afford one in 1998
- 900 DM installation cost
180 DM per month (60 DM per hop)

hub-nbg.franken.de, 1998

images/pict3_Lg.jpg

hub-nbg.franken.de, 1998

images/pict4_Lg.jpg

ISDN Leased Lines "SPV"

Not really a leased line
Basically only "flat rate calls" to one specific (fixed) destination
Available in national 1TR6 only
- some of them operated until 2006

Abusing Analog Lines, Part 1

ICU-T
- inverse of ISDN NTBA
- ISDN BRI (2x64k + 16k) over 12km of telephone line
Special ISDN routers without signaling to use even 16k D-channel for data!

Easy upgrade to get performance of a leased ISDN line out of an Analog-G

Leased Lines at KNF, 1997/1998

hub-fue.franken.de, undated

images/hub-fue-03_Lg.jpg

hub-fue.franken.de, undated

images/hub-fue-04_Lg.jpg

Abusing Analog Lines, Part 2

When the first DSL modems became available in the US

we imported some Ascend DSLpipe
with some firmwares, they could be used back-to-back (without DSLAM)
suddenly we could get speeds of 2.3 MBps over analog lines
- if they were not too long
- if they didn’t have in-line inductors
soon less expensive alternatives came up Pairgain (2000)

images/ascend.jpg

From Online Bistro to Internet Cafe

Falken’s Maze was an Online Bistro established in the 1990ies
- I became a regular around 1994
initially had four DOS PCs, each with a Modem, dedicated phone line and a call charge meter
- you could go there, eat + drink and use the PCs to log into BBSs
quickly became preferred meeting point of various nerds, BBS users, SYSOP meetings, etc.
PCs were networked with 10base2 and NetWare (DOOM!)
people started to dial into CompuServe, AOL, etc.
Internet became more popular, Falken’s Maze started subsidiary in Nuernberg
- ISDN SPV was used as Internet uplink

Summary

The first decade[s] of wide-area electronics communications
- were powered by a community of enthusiasts
- largely motivated by non-commercial motives
- without much corporate or government influence
BBS community / culture is a distinct sub-culture.
- different norms than HAM radio, Hackers, Free Software, but some of overlap

Conclusions

In the BBS days

networks were distributed, without single point of failure
infrastructure owned and operated by its users
connection speeds were largely symmetric
no data center vs. consumer separation with asymmetric speeds

This autonomy and de-centralization has been lost in the Internet age

Thanks

my uncle for giving me his old Olivetti acoustic coupler in 1990
Josef Groll, SysOp of SILVER.zer / SILVER.nbg.sub.org
Max Riegel, Martin Bokaemper, Joerg Kinzebach and KNF crew
Reinhold "unhold" Pretscher for Falken’s Maze
All sotware developers of BBS related software
All SysOps that made the BBS community possible

EOF

NO CARRIER

BBSs and Early Internet Access in Germany

Introduction

Circuit Switched Telephony

Hardware

Phone Charges

Acoustic Coupler

Modems

Modems

Modem Speeds / Standards

BBSs

Content

Technology/Software

Demo

The "BBS Protocol Stack"

Curiosity: Vector Graphics

Isolated BBSs

Points / Offline Messages

BBS networks (store + forward)

BBS network technology (examples)

Example: FIDOnet

Example: Z-Netz

Example: UseNet

Curiosity: Floppy Poll/Point

Internet

Internet with SLIP

Internet on PCs before Linux

ISDN

ISDN Terminal Adapter

How to get Internet Access?

Individual Network (IN) e.V.

Internet

Analog Leased Lines

hub-nbg.franken.de, 1998

hub-nbg.franken.de, 1998

ISDN Leased Lines "SPV"

Abusing Analog Lines, Part 1

Leased Lines at KNF, 1997/1998

hub-fue.franken.de, undated

hub-fue.franken.de, undated

Abusing Analog Lines, Part 2

From Online Bistro to Internet Cafe

Summary

Conclusions

Further Reading

Thanks

EOF