RE: [obix] FW: Directory Services and BIM-aware integration (UNCLASSIFIED)

["Considine, Toby" <Toby.Considine@unc.edu>]

Well if you never heard of it....

Electrical Layout IE - did that finally morph into SPARKie? If so, it was good, because ELie was the least goggle-able term ever.

tc
-----Original Message-----
From: obix@lists.oasis-open.org [mailto:obix@lists.oasis-open.org] On Behalf Of Bogen, Chris ERDC-RDE-ITL-MS
Sent: Thursday, March 27, 2014 9:12 AM
To: Toby Considine; oBIX@lists.oasis-open.org
Subject: RE: [obix] FW: Directory Services and BIM-aware integration (UNCLASSIFIED)

Classification: UNCLASSIFIED
Caveats: FOUO

Toby,

I am all on board with using LDAP for directory services, but I think you could strengthen the case if you stepped back from the "BIM Query" branding.  When you say that "I propose that we declare LDAP to be the Official query language for BIM," you have to know that in the least you'll get lots of distracting arguments from people that use BIM for completely different reasons (e.g. energy modeling, structural engineering, etc). If you can tweak the proposal a bit to avoid such culture wars then you are gold. The technical data mapping issues should be easy to accomplish and a demonstration should be relatively easy to develop.

One editorial comment:
line 57 - I have never heard of "ELie." Do you mean SPARKie (for electric systems)?

Regards

Chris Bogen, Ph.D.
Computer Scientist

-----Original Message-----
From: obix@lists.oasis-open.org [mailto:obix@lists.oasis-open.org] On Behalf Of Toby Considine
Sent: Thursday, March 20, 2014 10:04 AM
To: oBIX@lists.oasis-open.org
Subject: [obix] FW: Directory Services and BIM-aware integration

Fyi

 

tc

 

________________________________

"If something is not worth doing, it`s not worth doing well "    -- Peter Drucker

________________________________

Toby Considine
TC9, Inc

OASIS TC Chair: oBIX & WS-Calendar

OASIS TC Editor: EMIX, Energy Interoperation

SGIP Smart Grid Architecture Committee

  

Email: Toby.Considine@gmail.com <mailto:Toby.Considine@fac.unc.edu>
Phone: (919)619-2104

http://www.tcnine.com
blog: http://www.NewDaedalus.com 

 

From: Toby Considine [mailto:Toby.Considine@gmail.com]
Sent: Tuesday, March 18, 2014 11:02 AM
To: 'FMOC@lyris.nibs.org'
Subject: Directory Services and BIM-aware integration

 

I had to leave early from the FMOC meeting in Baltimore because my plane and the snow-delayed meeting overlapped. Before I left, I described an approach of adaptive re-use of LDAP in BIM applications.

 

I want to start a broader conversation on this.

 

I have had a chance to write down a few of my thoughts on this in greater detail in the hopes of starting a broader conversation. Using LDAP for BIM Queries lets us use a broadly available and well tested code base, gives us many opportunities to bake in as little or as much security as we need, and will get us to useful applications faster than building from scratch. 

 

For convenience, I am including the content of the attachment below, for easier reading on devices, etc. A PDF with line numbers for easier commenting can be found at

http://www.newdaedalus.com/storage/LDAP%20for%20Buildings%2020140318.pdf

 

Here is, as well, a link to some related thoughts from Automated Buildings.

http://automatedbuildings.com/news/mar14/columns/140304062707considine.html

 

Starter discussion follows.

 

Directory Services and BIM Queries

Toby Considine, toby.considine@gmail.com

There is a long-standing effort to define BIMQL, a language that allows inquiries and searches of a BIM model. Building Information Models are complex and each element may have multiple relationships with other elements. Often the key attribute you are searching for is an attribute of a related item. This has led to a well-studied effort to define a domain specific open query language for Building Information Models, i.e., BIMQL.

 

While BIMQL is aimed at the non-technical user, it still creates yet another slightly different syntax for inquiries. Selection can be based on a single attribute or property:

 

Select ?Var1 Where ?Var1.Color = "Yellow"

 

Or based upon relationships to another attribute. For example, this query finds all walls associated with a given space:

 

Select ?Var1 Where ?Var1.Attribute.GlobalId = "3iSzpa9d93jhTDB7hG0QBW"
Select ?Var2 := ?Var1.*(2)  Where ?Var2.EntityType = "IfcWallStandardCase"

 

The primary target of the BIMQL effort is to create plug-ins for a BIM model server as typified by that developed by bimserver.org model server.

 

The vision of this effort is both too large and too small. 

 

It is too large in that it aims to create an entirely new query language, one with its one syntax. This language requires a new code base, meaning it requires a new security model, and new security testing, and performance testing, and all those things that code to develop a new service that will be available on the internet must support. 

 

It is too small because it envisions the sole back-end of this query language to be a single platform, the BIMSERVER.ORG platform, in all its IFC glory and complexity. A query language should be abstracted above the underlying physical database and structure. A useful BIMQL will be asked to work above other systems, including Building Automation Systems (BAS), maintenance management systems (CMMS), asset management systems, et al.

 

One of the essential lessons of the internet is that small systems that can be used for many purposes are more useful than single purpose specifications that cannot be re-used. Simplicity of code makes it more likely that can be adequately for bugs and for completeness. This is especially important for security, which requires that each input, and each combination if inputs be carefully examined.

 

"Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it." 

- Brian W. Kernighan 

The predominant query language for directory services is the Lightweight Directory Access Protocol (LDAP). LDAP was developed as an easier way to get to information kept in phone company and enterprise directories. It is malleable and object oriented; widely directory objects include the person, the organizationalPerson, iNetOrgPerson, the eduPerson, etc. Numerous open source and commercial implementations exist. Many use the embedded directory information to manage authentication and authorization as well. LDAP is the most common way to communicate with Microsoft's Active Directory.

 

Many LDAP implementations have security as their predominant concern. Only members of the HR Committee who are members of senior management can see this report. Only Employees in the Registrar's office or a Student's advisor may see that student's full transcript. Only employees of Student Affairs can see all students' home addresses.

 

LDAP exists within a rich ecosystem of security applications and specifications. Directory Services Markup Language (DSML) provides LDAP functionality for those who want pure XML. Many LDAP applications support declarative security directly or support plugins to use eXtensible Access Control Markup Language (XACML) or other open specifications. LDAP is well tested, widely deployed code that scales well. 

LDAP databases are heterogeneous databases. If you use a corporate directory, it may already have people and rooms and equipment accessible to a single query. Directory access and directory information can easily be linked to role and employment status, either by LDAP federation, or LDAP replication.

 

LDAP relies on extensible directory objects. Directory objects are collections of named attributes that are formed according to RFC 1779 and RFC 2247. Using LDAP for BIM Queries would require definition of directory objects for BIM. COBie Lite provides formal semantics that can be easily adapted to meet the RFC requirements. BIM queries for information related to operations and maintenance can be achieved quickly. As existing efforts to use the approaches of COBie Lite in HVACie, ELie, SPie, et al. develop, new directory object sub-classes can be defined rapidly.

 

Not all building-based systems fit neatly into COBie categories. A medical facility would host medical equipment. Manufacturing systems have their own equipment classifications that are industry specific. Military facilities have their own business purposes for space and classifications for unique equipment types. The LDAP approach, which allows easy sub-classing and extension of all directory objects, can readily support novel information sets incorporated in BIM.

 

I propose that we declare LDAP to be the official query language for BIM. The BIMQL effort can be refocused on bridging one of the open source LDAP projects to a native BIM server. Numerous environments that do not have full BIM can even so take advantage of BIM queries. For example, a commissioning information set expressed in COBie Lite could load its data directly into an LDAP module even without a formal IFC model in the back. 

 

Programmers and applications that have not grown up in BIM will be able to start using BIM directory services right away. Owners and operators would be able to use some of the best tested and most secure code without waiting for long development. Numerous existing tools for managing directory synchronization would be available to building owners using multiple applications. Security and bug patches for LDAP services would be available from the wide world of existing LDAP software providers.

 

________________________________

"It is the theory that decides what can be observed."  -- Albert Einstein 

________________________________

Toby Considine
TC9, Inc

OASIS TC Chair: oBIX & WS-Calendar

OASIS TC Editor: EMIX, Energy Interoperation

SGIP Smart Grid Architecture Committee

  

Email: Toby.Considine@gmail.com <mailto:Toby.Considine@fac.unc.edu>
Phone: (919)619-2104

http://www.tcnine.com
blog: http://www.NewDaedalus.com 

 


Classification: UNCLASSIFIED
Caveats: FOUO



---------------------------------------------------------------------
To unsubscribe from this mail list, you must leave the OASIS TC that generates this mail.  Follow this link to all your TCs in OASIS at:
https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php