4 ms·

Ironically, this version of the header published in 1980 is what we still use to this day. IMHO Ethernet is one of the of great examples of backwards compatibi

Ironically, this version of the header published in 1980 is what we still use to this day. IMHO Ethernet is one of the of great examples of backwards compatibility in the computing world. Even the wireless standards present frames to the upper layers like they're Ethernet. It's also a counterexample to the bureaucracy of standards bodies --- the standard that actually became widely used was the one that got released first. The other example that comes to mind is OSI vs DoD(TCP/IP).

betaby 2y ago
OSI is very widely used, most of the large ISPs use it. End consumers are just unaware of that fact. See https://en.wikipedia.org/wiki/IS-IS https://en.wikipedia.org/wiki/IS-IS
- tialaramex 2y ago
  I think this is a stretch, like saying the X.500 Directory System is widely used based on the fact that PKIX is technically adapting X.509 and thus your TLS certificates depend on the X.500 directory system. End users aren't just "unaware" that it's actually the X.500 system, it functionally isn't the X.500 system, PKIX mandates an "alternate" scheme for the Internet and the directory called for by X.500 has never actually existed. Likewise then, IS-IS is the protocol that OSI standardized, but we're not using as part of an OSI system.
  - layer8 2y ago
    X.500 is widely used in the form of LDAP and Active Directory, however.
    - tristor 2y ago
      Active Directory is not based on X.500 and LDAP was directly created as an alternative to the DAP standard that is part of X.500. While X.500 is a precursor to both of these things, and influenced both of these things, and both of these things interoperated with X.500, they are not X.500. X.500 is for all intents and purposes pretty much dead in 2024, although I did deploy an X.500 based directory service in 2012 and it's probably still alive and running.
      - p_l 2y ago
        LDAP is just "lightweight" protocol for accessing an X.500 directory service. The semantics are the same for the accessed store, IIRC. The protocol definition explicitly talks about being used to access X.500 data stores as complementary interface to DAP (which requires lower layers of OSI stack vs LDAP's raw stream of bytes)
        tristor 2y ago
        Yes, that is why it was invented, as I alluded to. LDAP was an alternative to DAP. DAP is part of the X.500 standard, LDAP is not. LDAP when it was first invented was built to access an X.500 directory. That is no longer a base requirement and most directories in the wild are not built on X.500. Standards mean things, just because LDAP was originally built to access X.500 doesn't mean it's part of X.500, and X.500 is a very detailed and specific standard which most directory services no longer follow.
        GauntletWizard 2y ago
        To reiterate in a slightly different form: Ldap is an inheritor of, and successor to, DAP/X.500, but not backwards compatible and only superficially resembling it at this point.
      - lukeh 2y ago
        Ironically there's probably more X.500 remnants in Active Directory than in the UMich-derived LDAP servers, thanks to its Exchange 5.5 legacy.
- Hikikomori 2y ago
  Would call it stretch to say it was widely used by ISPs. Some old ones may still be using integrated IS-IS as their IGP (early OSPF had scaling issues and complicated solutions for that), but that's nothing like widely using the ISO stack. But they might have used IS-IS it to route NSAP in their network at some point in time to manage ATM-era equipment, the ISP I worked still had some ctunnels for that purpose, I doubt they still have them.
  - p_l 2y ago
    It was still widely used for IPv4 and v6 in 2000s. ex telco engineer told us that two major reasons was that IS-IS was simply more efficient, and that they didn't require IP communication between routers - meaning troubleshooting and management was easier than providing p2p routes for IP-based protocols.
    - Hikikomori 2y ago
      It's still widely used, among old ISPs because why switch when it's just as good or better than the alternative and your engineers know it best. But it's not the whole stack as implied in the first reply. It was popular primarily because OSPF didn't scale well with hundreds to thousands of routers with the minimal CPU power even large core routers had.
      - p_l 2y ago
        Scalability was one part. Later the fact that you didn't need separate routing setup for v6 also was part of it. But for a telco, the fact that you didn't have to setup IP connectivity in order for routers to see each other, was also a crucial ability.
        Hikikomori 2y ago
        OSPF has supported unnumbered links for a long time, don't need IP on the link with point to point and multicast.
rjsw 2y ago
OSI was usable as a wide area network before TCP/IP was.
- fanf2 2y ago
  [citation needed]
  - rjsw 2y ago
    Personal experience. Was developing OSI applications in 1989, you could order an X.25 circuit from your PTT and run OSI over that using the ISODE [1] toolkit. The earliest ISP in my country didn't start until 1992. [1] https://en.wikipedia.org/wiki/ISO_Development_Environment https://en.wikipedia.org/wiki/ISO_Development_Environment
    - zik 2y ago
      TCP/IP was developed in the 1970s and adopted as the protocol standard for ARPANET (the predecessor to the Internet) in 1983.
      - yusyusyus 2y ago
        and commercialization wasnt done until the like 1994. OSI as a successor was still proposed when the first BGP4 rfc came out. before commercialization happened, IP was mostly the realm of government and education.
        zik 2y ago
        I feel like your experience was quite different to mine. I used TCP/IP in the late 80s at university and doing commercial contract work. I remember OSI existing but at the places I worked it was treated as less common.
aylons 2y ago
> It's also a counterexample to the bureaucracy of standards bodies --- the standard that actually became widely used was the one that got released first. Sounds like a cautionary tale: whatever gets released first will stick. If you make a blunder, generations will have to live with it (like IPv4).

betaby 2y ago

OSI is very widely used, most of the large ISPs use it. End consumers are just unaware of that fact. See https://en.wikipedia.org/wiki/IS-IS https://en.wikipedia.org/wiki/IS-IS

tialaramex 2y ago
I think this is a stretch, like saying the X.500 Directory System is widely used based on the fact that PKIX is technically adapting X.509 and thus your TLS certificates depend on the X.500 directory system. End users aren't just "unaware" that it's actually the X.500 system, it functionally isn't the X.500 system, PKIX mandates an "alternate" scheme for the Internet and the directory called for by X.500 has never actually existed. Likewise then, IS-IS is the protocol that OSI standardized, but we're not using as part of an OSI system.
- layer8 2y ago
  X.500 is widely used in the form of LDAP and Active Directory, however.
  - tristor 2y ago
    Active Directory is not based on X.500 and LDAP was directly created as an alternative to the DAP standard that is part of X.500. While X.500 is a precursor to both of these things, and influenced both of these things, and both of these things interoperated with X.500, they are not X.500. X.500 is for all intents and purposes pretty much dead in 2024, although I did deploy an X.500 based directory service in 2012 and it's probably still alive and running.
    - p_l 2y ago
      LDAP is just "lightweight" protocol for accessing an X.500 directory service. The semantics are the same for the accessed store, IIRC. The protocol definition explicitly talks about being used to access X.500 data stores as complementary interface to DAP (which requires lower layers of OSI stack vs LDAP's raw stream of bytes)
      - tristor 2y ago
        Yes, that is why it was invented, as I alluded to. LDAP was an alternative to DAP. DAP is part of the X.500 standard, LDAP is not. LDAP when it was first invented was built to access an X.500 directory. That is no longer a base requirement and most directories in the wild are not built on X.500. Standards mean things, just because LDAP was originally built to access X.500 doesn't mean it's part of X.500, and X.500 is a very detailed and specific standard which most directory services no longer follow.
        GauntletWizard 2y ago
        To reiterate in a slightly different form: Ldap is an inheritor of, and successor to, DAP/X.500, but not backwards compatible and only superficially resembling it at this point.
    - lukeh 2y ago
      Ironically there's probably more X.500 remnants in Active Directory than in the UMich-derived LDAP servers, thanks to its Exchange 5.5 legacy.
Hikikomori 2y ago
Would call it stretch to say it was widely used by ISPs. Some old ones may still be using integrated IS-IS as their IGP (early OSPF had scaling issues and complicated solutions for that), but that's nothing like widely using the ISO stack. But they might have used IS-IS it to route NSAP in their network at some point in time to manage ATM-era equipment, the ISP I worked still had some ctunnels for that purpose, I doubt they still have them.
- p_l 2y ago
  It was still widely used for IPv4 and v6 in 2000s. ex telco engineer told us that two major reasons was that IS-IS was simply more efficient, and that they didn't require IP communication between routers - meaning troubleshooting and management was easier than providing p2p routes for IP-based protocols.
  - Hikikomori 2y ago
    It's still widely used, among old ISPs because why switch when it's just as good or better than the alternative and your engineers know it best. But it's not the whole stack as implied in the first reply. It was popular primarily because OSPF didn't scale well with hundreds to thousands of routers with the minimal CPU power even large core routers had.
    - p_l 2y ago
      Scalability was one part. Later the fact that you didn't need separate routing setup for v6 also was part of it. But for a telco, the fact that you didn't have to setup IP connectivity in order for routers to see each other, was also a crucial ability.
      - Hikikomori 2y ago
        OSPF has supported unnumbered links for a long time, don't need IP on the link with point to point and multicast.

rjsw 2y ago

OSI was usable as a wide area network before TCP/IP was.

fanf2 2y ago
[citation needed]
- rjsw 2y ago
  Personal experience. Was developing OSI applications in 1989, you could order an X.25 circuit from your PTT and run OSI over that using the ISODE [1] toolkit. The earliest ISP in my country didn't start until 1992. [1] https://en.wikipedia.org/wiki/ISO_Development_Environment https://en.wikipedia.org/wiki/ISO_Development_Environment
  - zik 2y ago
    TCP/IP was developed in the 1970s and adopted as the protocol standard for ARPANET (the predecessor to the Internet) in 1983.
    - yusyusyus 2y ago
      and commercialization wasnt done until the like 1994. OSI as a successor was still proposed when the first BGP4 rfc came out. before commercialization happened, IP was mostly the realm of government and education.
      - zik 2y ago
        I feel like your experience was quite different to mine. I used TCP/IP in the late 80s at university and doing commercial contract work. I remember OSI existing but at the places I worked it was treated as less common.

aylons 2y ago

> It's also a counterexample to the bureaucracy of standards bodies --- the standard that actually became widely used was the one that got released first. Sounds like a cautionary tale: whatever gets released first will stick. If you make a blunder, generations will have to live with it (like IPv4).