# Why was LDAP named LIGHTWEIGHT directory access protocol? is there a heavy/full version? **URL:** \ **Category:** Factual Questions\ **Created:** [February 27, 2019, 1:15am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266 "2019-02-27T01:15:04Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [February 27, 2019, 1:15am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/1 "2019-02-27T01:15:04Z")
The directory services protocols, I’ve ever heard of are LDAP and Active Directory (which is based on LDAP). I know LDAP stands for Lightweight Directory Access Protocol. So, was there ever a heavy or full DAP, or something else that this is ‘light’ in comparison to? According to wikipedia ldap is named that because it uses less bandwidth than it’s predecessor (which isn’t named). A bit of digging around shows only protocols derived from LDAP, and Novell’s directory service (which was killed off by TCP/IP, DNS, and the various network file server protocols). So, what/who is LDAP lighter than today? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [February 27, 2019, 1:45am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/2 "2019-02-27T01:45:22Z")
The heavier version was DAP. > **[Directory Access Protocol](https://en.wikipedia.org/wiki/Directory_Access_Protocol)** > > Directory Access Protocol (DAP) is a computer networking standard promulgated by ITU-T and ISO in 1988 for accessing an X.500 directory service. DAP was intended to be used by client computer systems, but was not popular as there were few implementations of the full OSI protocol stack for desktop computers available to be run on the hardware and operating systems typical of that time. The basic operations of DAP: Bind, Read, List, Search, Compare, Modify, Add, Delete and ModifyRDN, were adapted ... It wasn’t widely implemented. ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [February 27, 2019, 2:36am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/3 "2019-02-27T02:36:58Z")
I read that page, but the description made me think it was more of a standard, and that LDAP was an example/implementation of it. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [February 27, 2019, 2:59am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/4 "2019-02-27T02:59:45Z")
As an aside: apart from LDAP, the second main way of talking to AD today is using COM. As a network protocol, that would be DCOM, which, I think, is built on RPC (remote procedure call) I think that x.500, the directory standard, was conceived as the directory required for x.400, the email service, which was heavier than Simple Mail Transport Protocol. So network protocols (such as LDAP) would have followed from the definition of the directory, not preceded it: indeed I think some early implementations used x.400 for replication. ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [February 27, 2019, 3:16am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/5 "2019-02-27T03:16:15Z")
> [@Melbourne](#): > > x.400, the email service, which was heavier than Simple Mail Transport Protocol. Not heavier so much as from a completely different universe: X.400 was from the OSI protocol suite, which competed with and lost to the Internet protocol suite, which has SMTP and POP (Post Office Protocol) for email. These days, people try to pretend the Internet folks implemented OSI or something, and try to forget that OSI was a competing system which is now almost completely dead. ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [February 28, 2019, 5:20am UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/6 "2019-02-28T05:20:29Z")
> [@Derleth](#): > > These days, people try to pretend the Internet folks implemented OSI or something, and try to forget that OSI was a competing system which is now almost completely dead. That’s how it’s still taught. Every networking class I’ve been in has included the OSI model but presented it as an abstract model or paradigm that modern protocols sort-of follow. Aside from the TCP/IP suite, I only ever remember hearing about ipx/spx over a decade ago, and even then it was as mostly dead protocol. Well, that and some routing protocols (e.g. ospf, eigrp, rip,etc.), but that’s a world all it’s own. I’ve never heard the OSI presented as an actual set of protocols or working network stack. I suppose it’s like the difference between an operating system (e.g. dos, windows 95), and a network operating system. Nowadays the concept of an OS that didn’t have a network stack built-in is utterly unimaginable, except as some sort of hellish punishment. ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [February 28, 2019, 9:59pm UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/7 "2019-02-28T21:59:17Z")
I think this is the first time I’ve seen mention about IPX/SPX in over 20 years. Wow. ---
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [February 28, 2019, 10:13pm UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/8 "2019-02-28T22:13:55Z")
> [@Derleth](#): > > These days, people try to pretend the Internet folks implemented OSI or something, and try to forget that OSI was a competing system which is now almost completely dead. My understanding is that the OSI model is a conceptual model they teach people on how to think about the different layers of networking, from low level (physical) to high level (application/ports and such) It’s specifically not tied to any particular protocols, like x.500 or x.400 There was also an OSI protocol suite which was a network stack designed to provide a protocol for each layer of the OSI model. This is where x.500, x.400 come in. They’re a proposed networking suite/stack for each layer of the OSI model. That’s what you’re talking about. TCP/IP won out, and the OSI protocol suite is largely irrelevant, but the OSI model is still taught as a conceptual tool to understand a network stack. ---
**Author:** ![Slash1972](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/slash1972/32/6461_2.png) [@Slash1972](https://boards.straightdope.com/u/Slash1972)\ **Post date:** [March 1, 2019, 1:44pm UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/9 "2019-03-01T13:44:50Z")
> [@SenorBeef](#): > > TCP/IP won out, and the OSI protocol suite is largely irrelevant, but the OSI model is still taught as a conceptual tool to understand a network stack. Yep. In every friggin’ class, no matter how advanced ☹ Please Do Not Throw Sausage Pizza Away!! ---
**Author:** ![Pantastic](https://avatars.discourse-cdn.com/v4/letter/p/3bc359/32.png) [@Pantastic](https://boards.straightdope.com/u/Pantastic)\ **Post date:** [March 1, 2019, 3:07pm UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/10 "2019-03-01T15:07:35Z")
> [@dstarfire](#): > > Aside from the TCP/IP suite, I only ever remember hearing about ipx/spx over a decade ago, and even then it was as mostly dead protocol. In the early to mid 90s there were a variety of competing protocols and network types in use, and you needed to be aware of them if you were in IT. By the end of the 90s, TCP/IP on ethernet had solidly won out. There were some holdouts, but it’s really going on two decades since the others were in widespread use for ordinary networks. > [@SenorBeef](#): > > My understanding is that the OSI model is a conceptual model they teach people on how to think about the different layers of networking, from low level (physical) to high level (application/ports and such) Because I was always taught it as the “seven layer OSI model”, I always think of a Seven Layer Burrito from Taco Bell when it’s discussed. I’m pretty sure the people who worked hard to create the OSI model would prefer to be remembered as something other than the “Seven layer OSI Burrito”, but that’s life. ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [March 1, 2019, 6:35pm UTC](https://boards.straightdope.com/t/why-was-ldap-named-lightweight-directory-access-protocol-is-there-a-heavy-full-version/830266/11 "2019-03-01T18:35:03Z")
Interestingly, there’s a four-layer TCP model: > **[Four Layers of original TCP/IP model, Functions of four layers of TCP/IP model](https://www.omnisecu.com/tcpip/tcpip-model.php)** > > This lesson explains four layers of original TCP/IP model, Functions of four layers of TCP/IP model, Application Layer, Transport Layer, Internet Layer, Network Access Layer [https://docs.oracle.com/cd/E19683-01/806-4075/ipov-10/index.html](https://docs.oracle.com/cd/E19683-01/806-4075/ipov-10/index.html) Application, Transport, Internet, Network Access … and now I see that Oracle (pbuh) claims that it’s five layers, and separates Data Link from Physical. Do you kinda get the sense that the Internet People weren’t all that impressed with the notion of layers? That’s only because they weren’t: > **[Internet protocol suite](https://en.wikipedia.org/wiki/Internet_protocol_suite)** > > The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suite are the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP). Early versions of this networking model were known as the Department of Defense (DoD) model because the research and development were funded b... > [@](#): > > The IETF protocol development effort is not concerned with strict layering. Some of its protocols may not fit cleanly into the OSI model, although RFCs sometimes refer to it and often use the old OSI layer numbers. The IETF has repeatedly stated[sup][citation needed][/sup] that Internet protocol and architecture development is not intended to be OSI-compliant. [RFC 3439](https://tools.ietf.org/html/rfc3439), addressing Internet architecture, contains a section entitled: “Layering Considered Harmful”.[sup][40][/sup] The IETF is the Internet Engineering Task Force. They are as close to authoritative on The Internet as any single group can be. So they teach that the IETF is implementing the OSI Vision. I guess too many Big Important Organizations invested too much in OSI to accept that it was a bust, so now they have to rewrite history to pretend that there were never any OSI protocols, that the Arpanet/IETF people were on board with the seven-layer model from day one, and that the Internet is still an implementation of the OSI model. So it goes.