5 ms·

OSI: The Internet That Wasn’t (2013)

75 points by ghshephard 12y ago

hga 12y ago
Eh. The fact that you had to spend around $1,000 to buy the set of manuals required, back when that was perhaps $2,000 in today's dollars, was probably a bigger factor than the article makes it out to be. Standards organizations like ISO and ANSI, at least back then, made their money selling manuals, which just doesn't work for something so ubiquitous in the number of people who have to know details. Another problem that I read about at the time is that some of the ISO protocols didn't work. The "ISORMites" (http://www.amazon.com/Elements-Networking-Style-Animadversions-Intercomputer/dp/0595088791 http://www.amazon.com/Elements-Networking-Style-Animadversio...) were reported to be contemptuous of the Internet protocols, their origin from the "US Department of Death", etc. ... and didn't have a policy like the IETF's "running code wins" approach. More generally, per http://www.ietf.org/tao.html http://www.ietf.org/tao.html "One of the 'founding beliefs' is embodied in an early quote about the IETF from David Clark: 'We reject kings, presidents and voting. We believe in rough consensus and running code'"
jauer 12y ago
Oddly enough some OSI protocols live on at the foundation of IP networks in the form of CLNS & IS-IS. IS-IS is a internal routing protocol sometimes used instead of OSPF.
- jws 12y ago
  ASN.1 managed to infest some internet protocols like SNMP and SSL certificates. It's one of those solutions to a problem that shows its committee heritage and ends up being ludicrously complicated to implement because of all the edge cases. Lots of software has been compromised through flawed ASN.1 and X.509 decoders. I'm old enough to remember back in the day when our customer (the biggest possible customer) allowed us to implement early versions using SMTP, but we had to design and plan to switch to X.400 since that was going to be the real standard. It was a strange era. We had things that worked, but everyone knew that the whole industry was going to switch to something completely different that solved all the same problems for a reason no one in the trenches really understood. Except the dates for switching kept moving and the software for the new way never really quite arrived in working order or with enough features to move.
  - ghshephard 12y ago
    LDAP as well. Tim Howes once told me if he had to do it all over again, he would have not used ASN.1, would have done a simple text protocol.
Animats 12y ago
OSI's answer to TCP, TP4, was implemented in Windows 2000. TP4 assumed a reasonably reliable data path, probably an X.25 virtual circuit, underneath. It didn't have all the timing, reordering, retransmit, and congestion control machinery that lets TCP work over bad links. On the other hand, the OSI crowd had, at the time, more experience with scaling and routing. IP's class A, B and C networks, autonomous system numbers, and Border Gateway Protocol didn't scale well. Routing in the Internet is still something of a hack. Today's routers almost have to have an in-memory table mapping all 4 billion IPv4 addresses to Autonomous System Numbers. If memory wasn't so cheap, we'd be having real problems.
- tjgq 12y ago
  If memory wasn't so cheap, we would have transitioned to IPv6 long ago instead of coping with an ever increasing global routing table.
  - ghshephard 12y ago
    IANA and the RIRs are stepping away from their requirement that everyone route through their ISP's parent space. They quickly discovered there are a lot of reasons why Provider Independent Address Space (PIAS) is critical to any real business, and that nobody is going to re-number when they change ISPs (not to mention the hassle of having to deal with multi-site environments). The entire concept was a pipe dream. If they hadn't yielded on PIAS then every enterprise network engineer out there was just going to deploy in RFC 4193 ULA space, say screw you to the IETF and implement RFC 6296 - NPTv6 on their perimeter. Net-Net - Once IPv6 starts to get traction, we're going to have routing tables of roughly the same size, but they'll just consist of /48s instead of /20s.
    - tjgq 12y ago
      Deploying RFC 4193 at least would not pollute the global routing table with lots of short prefixes. Those enterprise networks would pay for that flexibility themselves instead of forcing the cost onto the whole Internet.
deleted 12y ago
[deleted]
ghshephard 12y ago
I was working at Hughes Canada Systems Division in 1994/1995, and they had an entire division dedicated to developing a next generation Air Traffic Control system - it had been mandated about 4-5 years earlier, that this project had to be written using OSI protocol stack. They had been struggling for about 4 years, and still hadn't managed to get the protocol stack on their operating systems interoperating properly. There were dozens of people working on this project too. Total Fiasco. They ended up scrapping most of their work.
- walshemj 12y ago
  Interesting when I worked for BT I worked on OSI interconnects for the UK its not that hard once you grok asn.1 to workout what is going on. My boss once watched a trace I was running stoped it and pointed to a particular dword and said that's a Sprint ADMD you can tell as they don't to that part of the had shake properly
jclish 12y ago
The 7 layer model lives on. It remains a good reference point for discussing networking.
- kabdib 12y ago
  Seven layers are a procrustean bed, at best. The model might be useful as a starting point, but really all it means is "good design uses layers." When you start discussing actual networking implementations, trying to fit a what you're doing into "where exactly this fits in the ISO model, and it's wrong if it doesn't fit" is a bad way to think. Devices that mix layers can do pretty interesting work, too (e.g., inspection of packets for security purposes, smart buffering for controlling host load, etc.). So the "every layer only talks to the layers immediately above and below" is kind of suspect, at least as dogma. There are probably other examples in very high bandwidth systems where you want to skip layers for performance reasons.
- tjgq 12y ago
  Although I'm not really sympathetic to the OSI model, it did get some things right. For instance, witness how almost every TCP/IP protocol has to roll out its own session layer for authentication purposes...
- spydum 12y ago
  Indeed, All People Seem To Need Data Processing.
coderjames 12y ago
We're actually integrating an OSI-based network stack into our avionics datalink product at work right now. The next generation of digital air traffic control between aircraft and the ground towers is an OSI stack. Proprietary application in layer 7 and avionics-specific layers 2 and 1, but everything in between is bog-standard OSI (TP4 & IDRP, IS-IS & CLNP, 8208). Interesting protocol suite, and it will be keeping aircraft going the right direction for the next 25+ years.
- ghshephard 12y ago
  Hilarious - a bit further down I mentioned how Hughes Canada Systems division had a team hard at work on that project in 1994/1995. I thought it had been scrapped - apparently not.
- walshemj 12y ago
  That is interesting I did in the summer go over to hanslope park (a technical out station for the Foreign office) for an interview and one of the technologies mentioned was OSI
- unethical_ban 12y ago
  To what end are non TCP/IP/Ethernet tools used?
ivancamilov 12y ago
"OSI has been forgotten by all but a handful of veterans of the Internet-OSI standards wars." Hardly forgotten, I learned about OSI at the same time I studied TCP/IP back in college. And I'm hardly a veteran, since I graduated in '09.
- ghshephard 12y ago
  OSI model, or OSI protocols? Everyone knows the OSI model - but outside of Avionics, you won't find that many people who know the protocol details beyond knowing they exist. And that TP4 is a thing.
  - walshemj 12y ago
    You can tell people who relay know OSI by asking them which level MIDI is and critique CISCO'S asertation that its a layer 5
StephenFalken 12y ago
There is a quite interesting book where the author (John Day) shares an inside view about the OSI committees back in the 70's and 80's, and its endless discussions: "Patterns in Network Architecture: A Return to Fundamentals" [1] [1] http://www.amazon.com/Patterns-Network-Architecture-Fundamentals-paperback/dp/0137063385 http://www.amazon.com/Patterns-Network-Architecture-Fundamen...
graycat 12y ago
I remember working with that ISO, OSI, C-MIP/C-MIS, ASN.1, *registration hierarchy, etc. stuff. Worst interval in my career. Finally I began to understand: The standards meetings were in Paris, Rome, London, Munich, ...!
- walshemj 12y ago
  The OSI was working to the one PTT per country model your government controlled/owned phone company.
aidenn0 12y ago
Ah, reading about some of the early packet-switch debates reminds me of the time my dad called me up and said "I crossed off one of my bucket list items: Vint Cerf called me a 'circuit-switched bigot'"
tankenmate 12y ago
One advantage that circuit routing has over stateless routing is that of largely painless muxing / demuxing; and hence almost no buffer bloat. SONET can mux multiple channels without the need for a single buffer. Obviously the downside is the lack of flexibility, interdependency and hence increased fragility.

75 points by ghshephard 12y ago

hga 12y ago

Eh. The fact that you had to spend around $1,000 to buy the set of manuals required, back when that was perhaps $2,000 in today's dollars, was probably a bigger factor than the article makes it out to be. Standards organizations like ISO and ANSI, at least back then, made their money selling manuals, which just doesn't work for something so ubiquitous in the number of people who have to know details. Another problem that I read about at the time is that some of the ISO protocols didn't work. The "ISORMites" (http://www.amazon.com/Elements-Networking-Style-Animadversions-Intercomputer/dp/0595088791 http://www.amazon.com/Elements-Networking-Style-Animadversio...) were reported to be contemptuous of the Internet protocols, their origin from the "US Department of Death", etc. ... and didn't have a policy like the IETF's "running code wins" approach. More generally, per http://www.ietf.org/tao.html http://www.ietf.org/tao.html "One of the 'founding beliefs' is embodied in an early quote about the IETF from David Clark: 'We reject kings, presidents and voting. We believe in rough consensus and running code'"

jauer 12y ago

Oddly enough some OSI protocols live on at the foundation of IP networks in the form of CLNS & IS-IS. IS-IS is a internal routing protocol sometimes used instead of OSPF.

jws 12y ago
ASN.1 managed to infest some internet protocols like SNMP and SSL certificates. It's one of those solutions to a problem that shows its committee heritage and ends up being ludicrously complicated to implement because of all the edge cases. Lots of software has been compromised through flawed ASN.1 and X.509 decoders. I'm old enough to remember back in the day when our customer (the biggest possible customer) allowed us to implement early versions using SMTP, but we had to design and plan to switch to X.400 since that was going to be the real standard. It was a strange era. We had things that worked, but everyone knew that the whole industry was going to switch to something completely different that solved all the same problems for a reason no one in the trenches really understood. Except the dates for switching kept moving and the software for the new way never really quite arrived in working order or with enough features to move.
- ghshephard 12y ago
  LDAP as well. Tim Howes once told me if he had to do it all over again, he would have not used ASN.1, would have done a simple text protocol.

Animats 12y ago

OSI's answer to TCP, TP4, was implemented in Windows 2000. TP4 assumed a reasonably reliable data path, probably an X.25 virtual circuit, underneath. It didn't have all the timing, reordering, retransmit, and congestion control machinery that lets TCP work over bad links. On the other hand, the OSI crowd had, at the time, more experience with scaling and routing. IP's class A, B and C networks, autonomous system numbers, and Border Gateway Protocol didn't scale well. Routing in the Internet is still something of a hack. Today's routers almost have to have an in-memory table mapping all 4 billion IPv4 addresses to Autonomous System Numbers. If memory wasn't so cheap, we'd be having real problems.

tjgq 12y ago
If memory wasn't so cheap, we would have transitioned to IPv6 long ago instead of coping with an ever increasing global routing table.
- ghshephard 12y ago
  IANA and the RIRs are stepping away from their requirement that everyone route through their ISP's parent space. They quickly discovered there are a lot of reasons why Provider Independent Address Space (PIAS) is critical to any real business, and that nobody is going to re-number when they change ISPs (not to mention the hassle of having to deal with multi-site environments). The entire concept was a pipe dream. If they hadn't yielded on PIAS then every enterprise network engineer out there was just going to deploy in RFC 4193 ULA space, say screw you to the IETF and implement RFC 6296 - NPTv6 on their perimeter. Net-Net - Once IPv6 starts to get traction, we're going to have routing tables of roughly the same size, but they'll just consist of /48s instead of /20s.
  - tjgq 12y ago
    Deploying RFC 4193 at least would not pollute the global routing table with lots of short prefixes. Those enterprise networks would pay for that flexibility themselves instead of forcing the cost onto the whole Internet.

deleted 12y ago

[deleted]

ghshephard 12y ago

I was working at Hughes Canada Systems Division in 1994/1995, and they had an entire division dedicated to developing a next generation Air Traffic Control system - it had been mandated about 4-5 years earlier, that this project had to be written using OSI protocol stack. They had been struggling for about 4 years, and still hadn't managed to get the protocol stack on their operating systems interoperating properly. There were dozens of people working on this project too. Total Fiasco. They ended up scrapping most of their work.

walshemj 12y ago
Interesting when I worked for BT I worked on OSI interconnects for the UK its not that hard once you grok asn.1 to workout what is going on. My boss once watched a trace I was running stoped it and pointed to a particular dword and said that's a Sprint ADMD you can tell as they don't to that part of the had shake properly

jclish 12y ago

The 7 layer model lives on. It remains a good reference point for discussing networking.

kabdib 12y ago
Seven layers are a procrustean bed, at best. The model might be useful as a starting point, but really all it means is "good design uses layers." When you start discussing actual networking implementations, trying to fit a what you're doing into "where exactly this fits in the ISO model, and it's wrong if it doesn't fit" is a bad way to think. Devices that mix layers can do pretty interesting work, too (e.g., inspection of packets for security purposes, smart buffering for controlling host load, etc.). So the "every layer only talks to the layers immediately above and below" is kind of suspect, at least as dogma. There are probably other examples in very high bandwidth systems where you want to skip layers for performance reasons.
tjgq 12y ago
Although I'm not really sympathetic to the OSI model, it did get some things right. For instance, witness how almost every TCP/IP protocol has to roll out its own session layer for authentication purposes...
spydum 12y ago
Indeed, All People Seem To Need Data Processing.

coderjames 12y ago

We're actually integrating an OSI-based network stack into our avionics datalink product at work right now. The next generation of digital air traffic control between aircraft and the ground towers is an OSI stack. Proprietary application in layer 7 and avionics-specific layers 2 and 1, but everything in between is bog-standard OSI (TP4 & IDRP, IS-IS & CLNP, 8208). Interesting protocol suite, and it will be keeping aircraft going the right direction for the next 25+ years.

ghshephard 12y ago
Hilarious - a bit further down I mentioned how Hughes Canada Systems division had a team hard at work on that project in 1994/1995. I thought it had been scrapped - apparently not.
walshemj 12y ago
That is interesting I did in the summer go over to hanslope park (a technical out station for the Foreign office) for an interview and one of the technologies mentioned was OSI
unethical_ban 12y ago
To what end are non TCP/IP/Ethernet tools used?

ivancamilov 12y ago

"OSI has been forgotten by all but a handful of veterans of the Internet-OSI standards wars." Hardly forgotten, I learned about OSI at the same time I studied TCP/IP back in college. And I'm hardly a veteran, since I graduated in '09.

ghshephard 12y ago
OSI model, or OSI protocols? Everyone knows the OSI model - but outside of Avionics, you won't find that many people who know the protocol details beyond knowing they exist. And that TP4 is a thing.
- walshemj 12y ago
  You can tell people who relay know OSI by asking them which level MIDI is and critique CISCO'S asertation that its a layer 5

StephenFalken 12y ago

There is a quite interesting book where the author (John Day) shares an inside view about the OSI committees back in the 70's and 80's, and its endless discussions: "Patterns in Network Architecture: A Return to Fundamentals" [1] [1] http://www.amazon.com/Patterns-Network-Architecture-Fundamentals-paperback/dp/0137063385 http://www.amazon.com/Patterns-Network-Architecture-Fundamen...

graycat 12y ago

I remember working with that ISO, OSI, C-MIP/C-MIS, ASN.1, *registration hierarchy, etc. stuff. Worst interval in my career. Finally I began to understand: The standards meetings were in Paris, Rome, London, Munich, ...!

walshemj 12y ago
The OSI was working to the one PTT per country model your government controlled/owned phone company.

aidenn0 12y ago

Ah, reading about some of the early packet-switch debates reminds me of the time my dad called me up and said "I crossed off one of my bucket list items: Vint Cerf called me a 'circuit-switched bigot'"

tankenmate 12y ago

One advantage that circuit routing has over stateless routing is that of largely painless muxing / demuxing; and hence almost no buffer bloat. SONET can mux multiple channels without the need for a single buffer. Obviously the downside is the lack of flexibility, interdependency and hence increased fragility.