Modems: A Biography

A biography of modem technology from its analog telephone dial-ups to digital "modems" (Broadband Cable/DSL); where a modem is a "modulator-demodulator in its original sense, with the name kept for simplicity.

Our Progress is Amazing

From 300 baud to 56k

In the beginning were 300 baud modems… they were slow… very slow.  The original 300 baud modems could communicate at 300 bits per second.  The most recent modems can communicate at up to 57.3 kilobits per second if you have a perfect telephone connection with no static.  At first, using 300 baud, you could read at the same speed as the text was displayed in real-time.  The 56k series of modems could print off a screen of text in about 2 seconds.  56k modems can transfer a 4 meg MP3 file in about 4 minutes, so they will do the job in a pinch but they aren't fantastic when compared with other data transfer solutions.  Flex has made a dial-up modem to BBS connection portal for free via the Plain Old Telephone System (POTS) for free to dial-up users to dial in to his network and offer a selection of BBSes to connect to once there.  It can be accessed via  I've been able to get 19.2k on it, but I have less than optimal telephone service where I'm at; but i can say that it does indeed work.  Originally using PC-compatible computers, the average BBS sysop had a maximum of four COM ports to attach modems to.  Now with the Internet and Linux this limit has been removed, with most systems offering 255 nodes available concurrently.  PHATstar has a dedicated dial-up number to access our “Teleporter” BBS Dial-up Redirector available 24/7 from 778-716-PHAT which terminates in British Columbia of Canada.  I have found that with the newer versions of Microsoft Windows, dial-up modems tend to be rather flaky, and would recommend to you to install an external POTS 56k modem on a Linux machine.  This has recently been tested and it does in fact work.  My installation was on a 64-bit Ubuntu Linux box using a DTECH 15ft USB to Serial cable that uses an FTDI chipset and there was success with that.  Please DO NOT use any USB to Serial cable that uses any other chipset than FTDI.  Most especially do not use a Prolific chipset in any USB to Serial cable.  They DO NOT work.  FTDI chipset technology may cost you $5 more, but is totally worth it as the alternatives simply, literally, do not work.  I made the mistake of getting a Prolific chipset cable from a well-recognized brand and picked up an item that in all practical senses is defective.  The cable alone wasn't defective, but rather the technology behind it was something that was completely borked (a brick AKA garbage AKA a total waste of money).  Linux has better backwards compatibility than Windows does.  It could be that you buy a brand new modem that isn't defective at all, but there are no modern device drivers for it on Windows, so its Linux or bust, and Linux does a fine job at it too.  It is also recommended to use an external modem as any computer that has a USB slot, even back to USB 2.0 specs can support it.  Furthermore, Linux is free and should be used as a replacement for Windows.  As for Apple Mac computers this setup will probably also work just fine, also via an FTDI USB to Serial cable, though I haven't tested this out; but it makes sense that this would work as well.  

Terminal Node Controllers

TNCs are radio modems, used in Amateur Radio.  The HF modems run rather slow at between 1200 bps to 4800 bps, with 9600 bps modems probably available at the time you read this in the near future.  The higher the frequency that they operate at the more data they can fit into the data stream.  As mentioned HF is very slow, but it has the ability to work over very long distances.  VHF TNCs can easily do 9600 baud and I remember seeing solutions that can get data across the radio communications link at 28.8 kbps, which is a very good speed for hobby use.  There are many different signaling technologies that can be used with radio modems, similar to how phone modems started off at 300 baud and grew to 56k.  Some encoding/decoding methods are slow, old, and non-impressive, however there are other newer transmission modes that feel really elite to use.

Cable and DSL Broadband "Modems"

Neither of these are actual modems, as a modem is a modulator/demodulator that implies converting analog to digital and digital to analog systems.  They are more like digital interfaces that transmit data via digital to digital links.  Because of this they can run really fast as there is no overhead data in conversion and because they aren't limited to a 64k channel, in which 56k modems use only less than 8k from the theoretical maximum, which is an amazing feat.  But still, cable and DSL links can transfer data in several orders of magnitude more than their predecessors.  It is common in this day and age to see these digital modems being able to transmit 10 Mbps and receive 100 Mbps.  This asynchronus communication setup is highly annoying, being able to transmit around one tenth the speed that you can receive at.  For a sysop running a BBS off of this connection it is certainly sub-par, though without a doubt still much faster than dial-up.  It is because of this speed limitation in sending data that people choose to host their systems off of vServers put up on the Internet with a server farm, as discussed on the homepage of this site under, “Connecting via the Internet's Telnet/SSH.”  The next logical step in the progression of speedy communications is Fibre Optic communications that travels at the speed of light, with several Fibre Optic data communication paths operating at the same time, in a parallel fashion, which is just amazing.

Fibre Optic Communication Modems

Fibre Modems are indeed modems, but rather than communicate over metallic cable the transmissions happen over tubes of light conducting material.  Most fibre connections run at 1 Gbit, with 10 Gbits available for large corporations or very elite hobbyists.  These connections don't come cheap, but the 1 Gbit options are still rather affordable if you get a synchronus connection where you can upload and download at the same high speeds rather than being capped for no good reason.  What some service providers do is hook up fibre connections to the nearest junction box near the resident and in between that and the house switch to using Gigabit ethernet @ 1gbit/second over Cat8 copper-based ethernet.  This is the most cost effective method of bringing in fibre optic communications to your own home.


It will frustrate you no end having an asynchronus Internet connection, so if at all avoidable get a connection with the same speeds sending as receiving.  If this isn't an option then choose a vServer from a reputable company.  I would recommend or its Canadian offerings at  They offer 400 Mbit connections for all levels of servers that you can lease from them, and 400 Mbits is more than you need to host a bulletin board system.  They also have deals so for the first few months you get it at around half the regular price.  Be careful though as you will be locked in for a 1 year term of service which you possibly may not be able to cancel without having to pay the full remainder of the length of service remaining up to that one-year period.  Hetzner is also an option but it isn't cheap.  Don't get servers based out of Germany as there are trolls that tell your server company that your system has an insecure setup having port 23 open.  They are highly abnoxious, annoying, and trolls, but with enough complaints to your Internet Server Host these pesky trolls can make your life hard.  Don't go German because of this.  I have tried German hosting from two seperate companies and found both to be targeted by these trolls.  American and Canadian server hosting does not appear to have this issue.