User:Howard C. Berkowitz

Professionally, I do network engineering and medical information systems, but am increasingly involved in electronics for commercial fishing (http://www.beachwerks.com), which, in turn, is leading to proposing some renewable biodiesel work. After many years in the Washington DC area, I am now in a fishing village on Cape Cod. As Monty Python would have it, it is far more productive to look at fishing there than in the middle of the Sahara. The biodiesel proposal is an elegant little concept of having seafood caught by diesel-powered fishing vessels, fried by local restaurants, whose waste vegetable oil comes back to our facility, and is converted into mixed biodiesel to go back into the boats.

In the networking realm, I've long been a participant in communications standards, passing knowledge forward in writing and teaching, developing routing and network management products, and architecting a good number of large service provider and enterprise networks. In the latter, to paraphrase from an old US television commercial, I'm not a physician but simulate them on computers.

At Citizendium, my areas of contribution are principally in military and intelligence areas. With great pleasure, I am again writing in one of my main professional areas, computer network engineering, which simply had become too painful at Wikipedia. I expect to be contributing in health sciences, particularly in regard to clinical computing and medical information management. Wikipedia, my most active area of contribution, at present, is in military and intelligence material. I have taken a Wikibreak from computer/data networking, with some specialized exceptions for things related to commercial fishing -- I'm afraid I grew weary of having to correct the same errors I have been seeing for a couple of decades, and one of the last straws was an argument over the definitions in a peer-reviewed article of which I was a coauthor. Occasionally, I contribute to medical articles, and a range of miscellaneous topics of interest such as cooking.

Citizendium contributions

I'll try to categorize these by the most relevant workgroup, although certain areas, especially intelligence, don't neatly match to a workgroup. +denotes articles where I was the primary author or ongoing editor at Wikipedia. Further below, I discuss my background and interests in the major fields.

Intelligence

While I started out calling many military, it's just as appropriate, with many, to add history, engineering, law, and assorted sciences.

The general discipline

• Intelligence cycle management
• Clandestine human-source intelligence and covert action (also has material pertinent to the formation of the Central Intelligence Agency)

US intelligence community specific

Started article at Citizendium

• Central Intelligence Agency+
• Clandestine human-source intelligence and covert action (also has general material)
• National Reconnaissance Office

General military

Created article at Citizendium

Air warfare planning Air-to-air missile Antiaircraft artillery Guided missile Precision-guided munition

Contributed to Citizendium article

United States Air Force

Special operations

US-independent

• Insurgency+

US-specific

• Foreign internal defense
• Unconventional warfare (United States doctrine)
• Special reconnaissance (also has global information)

Network engineering

My experience with communications standards goes back to the mid-seventies, variously with ISO/CCITT and ANSI to start, especially in network performance. I worked for GTE for a time, and had a good deal of exposure to the internals of telephone networks. As a member of the Federal Telecommunications Standards Committee (1976-1980), I got in at the beginning of what was to become OSI, and also got interested in survivable communications systems, including the (US) National Communications Systems and military networks intended to operate under the most extreme conditions. Those extremes tended to be that the network really needed to operate for 20 minutes or so, but you never knew when the 20 minutes would start, and would just have to cope with network elements randomly turning into mushroom clouds. This tied in with a lifelong interest in politicomilitary history.

The FTSC and National Communications System contributed, in the late seventies, to the ANSI Distributed Systems (DISY) architecture, which was a significant input into the OSI architecture. ISO 7498, the basic OSI Reference Model <e, was published in 1984. Even ignoring the eventual dominance of Internet protocols, there is a great deal of misunderstanding about OSI, because educators generally ignored supplemental ISO documents that clarified ISO 7498.

From 1986 to 1991, I was the first technical staff member at the Corporation for Open Systems, a not-for-profit industry research center for promoting and testing OSI and ISDN protocols. In addition to secretariat work with the various committees, I managed teams working on FTAM and X.25 test systems, and contributed to IEEE 802 test systems. One memorable experience was lecturing about X.25 testing in Japan, and had the horrible realization that my PowerPoint slides, translated into Japanese, had gotten into a different order than my English-language notes.

For around six years of my life, I explained how OSI was the answer, but eventually realized I didn't know the question.

The moving hand writes on the wall: "it's about IP, stupid"

By the early nineties, it was obvious that Internet protocols were indeed the answer, and I started to play in the Internet Engineering Task Force (IETF), North American Network Operators Group (NANOG) and the Internet Research Task Force (IRTF).

In the IETF, my main work has been in the Routing (especially BGP/IDR and OSPF) and Operations & Management Areas (especially BMWG & OPSEC), and, more as a lurker, Security and Real-time Applications & Infrastructure Area. I am an author or coauthor of RFC 1912, RFC 2071, RFC 2072, RFC 4098, and was a reviewer or contributor with many others. I've done quite a few tutorials and presentations available at www.nanog.org, and was a participant in "Team B" of the IRTF Future Domain Requirements effort, which essentially looked at the question "what comes after BGP?" Some of my most satisfying work came when I was first the product line manager for routing protocols in the carrier router group, and then in corporate research at Nortel, both working with standards and operational forums, and designing a next-generation router.

Why network architectures and standards?

The early days of computer networks were dominated by a few large companies such as IBM and DEC. In order promote interoperability and avoid a situation where a small number of vendors predominated, each with their own proprietary technology, it was necessary to introduce a set of open standards defining network protocols.

Another issue addressed by this model is maintaining the level of flexibility needed to adapt when new innovations are introduced. The earliest wide area networks (or WANs) ran over telephone lines and were used to link a small number of facilities.

Today, we rarely think about why Internet access has become so ubiquitous. Still, this is quite a technical achievement: a user may be connected to an Ethernet network, Fiber Distributed Data Interface (FDDI) or a wireless network in a coffee house. They may also use such diverse methods as DSL, cable, or dialup lines to "get online."

The Truth about Network Reference Models

There is a continuing and frustrating tendency, in Wikipedia articles on network architecture, to treat the OSI model as if it is still used other than as a teaching aid, and to try to “coerce” (using the lovely word choice of my colleague, Priscilla Oppenheimer) Internet Protocol Suite protocols into OSI layers. Layering, as an abstraction, is useful up to a point. It can be overused. An updated IETF architectural document, RFC3439, even contains a section entitled: "Layering Considered Harmful": Emphasizing layering as the key driver of architecture is not a feature of the TCP/IP model, but rather of OSI. Much confusion comes from attempts to force OSI-like layering onto an architecture that minimizes their use.

I have insufficient hair to tear it out whenever I try to explain that the Internet protocol suite was not intended to match OSI, was developed before OSI, the full set of OSI specifications (i.e., not just document ISO 7498) subdivide layers so that it is no longer seven, and that OSI has, in the real world, been relegated to a teaching tool. The Internet Protocol Suite has four layers, defined in RFC1122and no IETF document, as opposed to some nonauthoritative textbooks, say it has five.

No IETF standards-track document has accepted a five-layer model, and IETF documents indeed deprecate strict layering of all sorts. Given the lack of acceptance of the five-layer model by the body with technical responsibility for the protocol suite, it is not unreasonable to regard five-layer presentations as teaching aids, possibly to make the IP suite architecture more familiar to those students who were first exposed to layering using the OSI model. Comparisons between the IP and OSI suites can give some insight into the abstraction of layering, but trying to coerce Internet protocols, not designed with OSI in mind, can only lead to confusion.

Again, RFC1122 defines 4 layers. If anyone can find another IETF document that states the OSI model is followed, please cite it. Further, RFC 1122 was published in 1989, while the OSI Reference Model, ISO 7498, was published in 1984. If the RFC 1122 authors had wanted to be OSI compliant, they had the OSI definitions available to them. They didn't use them. Does that suggest they were not concerned with OSI compliance?

For Internet Protocol Suite architecture, textbooks are not authoritative; the IETF's work, particularly the Standards Track, is definitive for the Internet Protocol Suite. I've written networking textbooks, and, while I might clarify an IETF document, I certainly don't contend that textbooks are more definitive than the actual technical specifications created by expert, not beginning student or teacher, consensus.

Unfortunately not available free online AFAIK, there are ISO documents such as "Internal Organization of the Network Layer" , which splits the network layer nicely into three levels, logical (lower-layer agnostic), subnetwork (i.e., link technology) specific, and a mapping sublayer between them. ARP, with which many people struggle, drops perfectly into the mapping (technically subnetwork dependence convergence) between them. Another ISO document, "OSI Routeing [sic] Framework" , makes it clear that routing protocols, no matter what protocol carries their payloads, are layer management protocols for the network layer. Annex 4 to ISO 7498 gives the OSI Management Framework , with both system management and layer management components.

When the IETF was dealing with MPLS and some other things that "don't quite fit", and some people insisted on calling it "layer 2.5", the reality is that the IETF set up a "Sub-IP Area" and did the original work there. MPLS is now back under the Routing Area. There was also a Performance Implications of Link Characteristics (PILC) working group that has ended its effort, but also deals with sub-IP (archives at http://www.isi.edu/pilc/).

Why is Wikipedia having problems in network topics?

There is a great deal of valuable information on networking at Wikipedia. There is also a great deal of misinformation, partially due to networking experts leaving in frustration with the process of having authoritative definitions constantly changed by editors who found their high school or college textbook conflicted with primary sources or direct experience in developing networks and primary sources.

I'm one of those people. while I'll certainly stay involved in my profession, I've found the frustration of working with Wikipedia on serious network architecture is simply no fun at all. Oneof the most important real-world issues is that in terms of real-world products and networks, the 7-layer OSI model from the International Organization for Standardization is dead, and the less formal architectural models primarily associated with the Internet Engineering Task Force (IETF) and the Institute for Electrical and Electronic Engineers (IEEE) actually define what is done. Unfortunately, most introductory courses and books on networking keep the OSI model as a key part of their presentations, much as, I suppose, Dr. Frankenstein kept his undead monster alive.

If people want to keep insisting that IETF protocols must fit into the OSI reference model, if protocol payloads must be of layer N+1 if their payload is management (e.g., routing) for layer N, that there are five layers in the Internet reference model, may they enjoy themselves. It's not even that I've tried to impose an IP-centric view, although I have linked RFCs specifically saying that strict layering is considered harmful and RFC 1122 chose to ignore ISO 7498; I've even cited more detailed ISO documents -- but people want to keep insisting their incorrect textbooks are more authoritative, or "explain" to me about protocol encapsulation and layering.

In the real world, I've written four books on network engineering, Designing Addressing Architectures for Routing and Switching, Designing Routing and Switching Architectures for Enterprise Networks, WAN Survival Guide, and Building Service Provider Networks. My general sense is that vendor-independent traditional engineering books have a limited market, and I've been concentrating more on online publications. In the past, I've been involved in preparation for Cisco certifications, and still participate in mailing lists.

Military Science and Intelligence

While growing up, I rarely blew up things, preferring the more subtle threat of bacteriology. My mother, an Army reserve officer, did bring home assorted Field Manuals that would shock US Homeland Security.

In addition to military command and control, and participating in gaming and simulation, I've had a certain amount of exposure to intelligence research and analysis, and occasionally do open source intelligence consulting. Some of my graduate work was in strategic intelligence analysis.

War is hell. Still, there are moments that show the best of human virtues, such as Guy Gabaldon