28 April 2007

On the word "Tend"

Power tends to corrupt, and absolute power corrupts absolutely. Great men are almost always bad men.
Lord Action, letter to Mandell Creighton (1887)

When concepts of economics are explained, the use of the word "tend" or "tendency" often causes confusion. An important example is distinguishing between the known tendencies of economic actors, and better-known exceptions to those tendencies. It's important not to confuse the two.

Few would deny that private sector firms make mistakes, including very glaring and stupid ones; likewise, no one claims that all consumers are privately rational in any sense, let alone expectations. In the first case, the fact that private-sector firms make mistakes in planning or pricing is mitigated by the fact that it is very unlikely for all firms to make the same mistake for long. The tendency is for at least someone to identify the mistake and profit from it, thereby drawing attention to it. In the second case, judgments about the future rate of inflation, interest rates, and so forth are not likely to be consistently wrong (biased) UNLESS there is some reason for everyone to make the same mistake, like a sudden change in government policy (see REH).

The point of a tendency is that it is often overridden by random events; for example, it is possible for people to make huge errors about the demand for 3G cell phone service five years out But it is unlikely that those errors will be all in the same direction, since the point of a true error is that it is random. Even if such an event should occur, as perhaps the result of a hugely popular fad, there will be some force in place that tends to compel a correction. Again, if a firm makes a really huge error about the demand for 3G cell phone service, this will quickly be felt through losses, firings of executives, and so on.

When we say a certain thing tends to happen, it is usually a milder form of saying that it will happen. Lord Acton's quote is truthful, but there are notable cases where the person who held such power transcended it and was not corrupted; and there are cases where people appear to have acquired power for explicitly bad ends; in the latter case, it's difficult to say that the person was made corrupt, i.e., susceptible to wickedness, by the acquisition of power. Acton wants us to know that great men are almost always bad men, but not always bad men. The virtuous outlier may exist; and power may not so much corrupt, as enable evil.

However, Acton was not merely acknowledging the existence of exceptions. He was probably trying to point out that the various attributes of political power (in this example) have a dynamic that overcomes good will gradually, but decisively. This is a subtle distinction. Things being hosed down with water don't tend to become wet, they become wet. The sense of "spraying water all over a thing" is almost identical to the sense "that thing becoming wet." The two concepts amount to almost the same thing: wetness means recent contact with liquid. On the other hand, a tendency to become wet implies some intermediate cause. Acton meant (I think) that power, as extraordinary agency, is not in and of itself evil; his argument for liberty comes from the fact that the way power is concentrated into the hands of a ruler, is likely to transgress ethics, and leads to a generalized lassitude towards ethics on the part of the ruler. In other words, the conditions that caused absolute power also to create a moral wilderness for the ruler, leading to a thwarting of moral impulses and a desperate resort to immoral ones.

I am reminded of the concept of Maxwell's Daemon, a wonderful imaginary invention that consists of two chambers connected by a tiny sliding door; anytime a particle moving inside chamber A approaches the door, the daemon observes its velocity and opens the door if that velocity is higher than the average in chamber B. If not, the door remains closed. Conversely, anytime a particle in chamber B approaches the door that is moving more slowly than the average in B, the door opens to let it through. Such door would consume infinitesimally small amounts of energy itself, yet defeat the 2nd Law of Thermodynamics; heat transfer would be from cooler A to hotter B. While the molecules in B might be immensely hot, and those in A bitterly cold, and this would mean the average velocity of particles in A is lower than that in B, nevertheless, outliers in either direction would make it through the door often enough for the transfer to continue.

Now suppose the daemon finally broke down. It opens randomly, although as frequently as before. Being random, it will sometimes do what it was supposed to do, and there will still be gas molecules in B that are much slower than the average in A, which make it through the door. But the vast majority of molecules will be moving faster than that, and in the great majority of cases it will be the fast particles in B or the slow particles in A that get through. This will be a true example of a tendency. The temperature in A will be observed to rise, and that in B will noticeably fall, because temperature reflects the motion of many moles of particles. And the tendency to spell it "Maxwell's Demon" will tend to triumph.
ADDITIONAL READING: In searching for the Lord Acton quote, I noticed this excellent essay on the meaning and context of it. Special thanks to Brian Martin; here's a link to the rest of his online book, Information Liberation.

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27 April 2007

The Expert's Dilemma

A common problem faced by experts on a particular subject is hostility for ideological reasons. I've paid a lot of attention to this problem, and I think it's especially severe in economics. Economics, after all, professes to explain the whole of the social sciences using ideas that are basically pure deduction. The only other field of study I can think of that does this is theology. Economics requires a set of basic premises that are assumed to be immutably true, and while these premises are few in number, a vast body of assumptions is derived from them. These include the proposition that for-profit, privately-owned enterprises tend to allocate resources correctly, that consumers tend to make rational and free choices about how many hours they work per year, or how much they will spend on their home, or if they will take public transit to work, or any other consumption decision.

Economics, because of the deductive foundation of its judgment, is of all the branches of study the most ideological. Computer science is another field of study that tends to be very ideologically bound, since critiques of its decisions suffer the same problems as in economics: the web of human motives and abilities is so complex that it relies mainly on deduction from basic principles. A common defense is, "In technology, something either works or it doesn't"; because of this, IT is supposed to be liberated from dependence on induction. In my experience, there is almost no non-trivial technical decision that is so bad that it cannot be made to "work" to some decision-maker's satisfaction.

Of course I do not want to imply that this proves economics or computer science are bad disciplines, or that their practitioners are lying quacks. I am just pointing out a difficulty that confronts both fields. I think it is important for practitioners to acknowledge this (which is why when I was writing about Unix I was so impressed by Eric Raymond's books and essays.) In fact, ideology is a common tool that allows people to form orderly and structured judgments. It is very frequently used as a substitute for thinking, but it is so useful to public thinking and problem-solving that it is useful nonetheless. Therefore, I cannot bemoan the presence of ideology, either. Even if I thought it was an unmitigated bad, I should still have to concede that it is a part of life and shall remain so.

At the same time, however, we often see occasions when an expert discovers facts that challenge the foundational beliefs of an ideology. The expert is a loyal supporter of the ideology, but he cannot deny the evidence. The example that comes to mind is Eric Raymond's essay, "The Cathedral and the Bazaar" (CatB; discussed here). I read the essay, then several responses that Mr. Raymond had graciously linked to at his essay page. One response to CatB provoked this aggravated rebuttal from Raymond:
Nikolai Bezroukov's article in First Monday [critiquing CatB], unfortunately, adds almost nothing useful to the debate. Instead, Mr. Bezroukov has constructed a straw man he calls vulgar Raymondism which bears so little resemblance to the actual content of my writings and talks that I have to question whether he has actually studied the work he is attacking. If vulgar Raymondism existed, I would be its harshest critic.

I wanted to like this paper. I wanted to learn from it. But I began to realize this was unlikely when, three paragraphs in, I tripped over the following: he promoted an overoptimistic and simplistic view of open source, as a variant of socialist (or, to be more exact, vulgar Marxist) interpretation of software development.

There are many sins of which I can reasonably be accused, but the imputation of vulgar Marxism won't stand up to even a casual reading of my papers. In CatB, I analogize open-source development to a free market in Adam Smith's sense and use the terminology of classical (capitalist) economics to describe it. In HtN I advance an argument for the biological groundedness of property rights and cite Ayn Rand approvingly on the dangers of altruism.
The first point I want to make here is that I would think long and hard before I made a facial challenge of anything Mr. Raymond said about computer software development. He has qualifications that are hard to match, let alone exceed. His knowledge of computer science is huge, he's devoted a lot of time to pondering the organizational or cultural implications of it, and he has a fair understanding of many other fields besides that one. Also, as it happens, he's right—even a casual reading of his work doesn't allow anyone to imagine that he's a socialist.

So I would say he's an expert, and also that he's ideologically compatible with the prevailing economic system and its ideological proclivities. If a capitalist party membership book existed, his would be in good order. And yet, his observations might be carelessly construed to negate the ideal intellectual property regime:
Nikolai Bezroukov: In a really Marxist fashion, Eric Raymond wrote in Homesteading the Noosphere "ultimately, the industrial-capitalist mode of software production was doomed to be out competed from the moment capitalism began to create enough of a wealth surplus for many programmers to live in a post-scarcity gift culture." I used to live in one society that claimed to "outcompete" capitalism long enough to be skeptical.
I have familiarity with the practice of Marxist party congress criticisms, having read much of E.H. Carr's history of the Bolshevik Revolution; and I have to say that Bezroukov's article really does sound like he imagines he's criticizing Raymond for taking the "line" of (say) "undisciplined Preobrazhenskyism" or something. The fact that Raymond actually has a huge volume of objective, reliable experience with the matter he's writing about, means nothing to Bezroukov: Raymond's somehow gone pink.

Bezroukov is not a dummy, and he has his own considerable credentials. My own suspicion was that he needed to "prove" his own ideological reliability by attacking someone who had been insufficiently guarded in his corporation-unfriendly observations. As a minor functionary in the actual institutional apparatus of the capitalist state-corporation nexus, he had to attack an attacker of Microsoft—and make him menacing. (Raymond never wrote anything like "Microsoft must be destroyed.") That attended to, he could discuss open source software as a sociological phenomenon. But by attacking Raymond as an ideologically unsafe line wobble, he illustrated that absolutely no one is safe. One must toe the official line, regardless of what one has seen, or face the consequences.

This is the Expert's Dilemma.

UPDATE (17 September 2011): Oddly enough, I stumbled across Dr. Bezroukov's reviews on Amazon and of course had no recollection of this critical post I had written five years ago. I feel I own him an apology. It turns out we have very similar attitudes about market fundamentalism, and I had completely misunderstood him. His approach was to criticize Raymond from the position of Raymond's own obsessive anti-Communism, an approach I usually attempt to imitate and ought to have recognized.

It's been five years and I suspect absolutely no one has ever read this webpage. I liked so many of Dr. Bezroukov's book reviews (e.g., this one and this one) I paid his website a visit, where I noticed a lot of material critical of Eric Raymond. Something in the murky depths of my memory stirred and then I remembered this essay.

Nevertheless, the point still stands, despite an imperfect example.

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18 April 2007


One of the purposes of this blog is to explore the way technology and the built environment have molded our lives. That's a very broad subject, and I've been torn between focusing on writing about technology on which I need to be conversant for work, and the sociology of material culture. One of the blogs I've noticed, but feared was a bit too far afield to link to on the sidebar (at least, for now) is Subtopia, a blog devoted to the militarization of the urban landscape.

Click for larger image

When I first became aware of the subject, I was astonished at the degree of specialization. Surely there's not much to say about this subject? On the other hand, I know I have a lot of hobbyhorses that would appear to be exhausted in no time. And after a few minutes of utterly fascinating exploration, I discovered that Subtopia has an endless reservoir of material. First, with the phenomena known collectively (and wrongly) as "globalization," the world in which we live has become criss-crossed with defensive boundaries. The most famous are probably the Israeli "security fence" and the Mexico-US border. Other famous examples include the border between the Koreas, the Spanish (Ceuta)-Moroccan border, and neighborhood barriers enforcing segregation. This enforcement of borders, though, is by no means confined to windswept, austere border regions. The mania for prisons and gated communities reflects the deep divisions imposed by the soaring disparities in income or privilege; surveillance cameras and electronic sensors are used to regulate and control movement, even when that movement is sanctioned.

Now, I want to make some clarifications here for my readers. I'm not opposed to walls or controls or regulations. To be honest, looking at photos of the barrier between the US and Mexico fills me with great shame and sorrow, but I understand the demand for them. The industrial system per se seems to require hard boundaries as a form of heat engine, rather the way the invention of the steam engine required the ability to machine tool steel containers for high-pressures. Still, I believe people need to know the artificiality and occasional barbarism of these barriers. Perhaps then they might realize how arbitrary and random their station in life is.

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15 April 2007

[Virtual] World Wide War

Fast-Moving Zombies: Botnets Stay a Step Ahead of the Fixes, Greg Goth, IEEE

Over the winter I and my contacts at the company's ISP noticed a distinct surge in "malware." In communication with my company's ISP, they occasionally mentioned the desperation and frustration of warfare. Mostly the malware was spam, which has been roughly doubling every year since at least 2000.

Much of the increase has been as the result of "botware," or malicious computer programs installed against the user's will and knowledge. Botware floods the internet with literally trillions of e-mails each year, and utilizes the latest spam-thwarting technology.
Users who might be truly interested in discovering whether their computers have been turned into bots can do a fairly simple check from the command prompt. Typing netstat -an reveals both local and foreign IP addresses and the port numbers via which they’ve communicated during the computer’s current session. Users who don’t use Internet Relay Chat (IRC) and see port 6667 displayed on the list of addresses in the command prompt can almost guarantee that their machines have been hijacked.
IRC's are easily installed and activated on Windows machines since the OS was designed to automatically load patches and other programs from the web.
Trend Micro’s Moriarty says IRC is still a bot boulevard, but other protocols are now being exploited as well. “IRC is still predominantly the main source of communication,” Moriarty says. “However, starting around April and May of last year, we started noticing bots starting to use port 80. So now they’re blending in with the normal mix of Web traffic, and it gets a little more difficult to separate the wheat from the chaff.”

Another industry veteran also says he sees a trend away from IRC bots. Andre M. DiMino, cofounder of the Shadowserver Foundation, a volunteer-run resource center focusing on malware, botnets, and electronic fraud activity, says P2P botnets are making a strong appearance. “It’s definitely shifting,” DiMino says. “There’s a lot of P2P bot traffic now. For instance, the Nugache worm ... was a real classic P2P worm. We now believe it was originally released as a proof-of concept on [the normally unassigned] port 8 because we’re seeing more variants. Originally, it was really easy to find — it had a hard-coded list of IPs and was kind of dumb when we first saw it, but now appears to be proof-of-concept. I kind of look at it as IRC botnets could be the bad guys’ honeypots — we’ll all be looking for IRC bots,but the real bad stuff will start happening on other vectors.”
What are some things that Windows users can do to reduce the risk of malware? Basically the problem is that most Windows boxes are configured so that users can log in only as an administrator. I've noticed that theis is not the case in Windows XP, where computer users must chose among a variety of possible identities. Still, a lot of users do tend to log on as an administrator all the time. In this mode, Windows has standing permission to install pretty much anything on the hard drive. Another countermeasure implemented by ISP's is to configure customer machines so they prevent outgoing IRC transmissions:
For example, whereas XP Service Pack 2 has no easily discernible way for users to configure their machines to avoid outgoing IRC communications, some ISP home network equipment does. AT&T’s broadband wireless router manufactured by 2Wire, for instance, lets users disable outgoing IRC traffic, but it’s not the default setting. And some users have been frustrated by system crashes caused by downloading other free firewalls that are incompatible with their ISP-supplied software, XP firewall, or both.
What puzzles me, though, is not merely the invasion of the bots--it's the deluge of spam, spam replete with alarm words that one could reasonably expect an automated spam filter to detect. Is the proliferation of spambots and botnets just maxing out the filters?
ADDITIONAL READING: "A Taxonomy of Botnets" (PDF), by Dagon, Gu, Zou, Grizzard, & Dwivedi;

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12 April 2007


Bluetooth is a form of wireless interface between devices supposedly belonging to a single user. More formally, it is the specification for connecting cell phones, computers, and personal digital assistants (PDAs) using short range radio transmissions. It is different from Wi-Fi in so far as Wi-Fi connects many computers at a single address (to the Internet), Bluetooth is used to connect a small number of electronic devices to each other.

("At a single address" is a deliberately vague term. "Address," here, refers to an office, cafeteria, residence, of any physical size. Some Wi-Fi hot spots are immense, such as the City of Philadelpha.)

General Outline
Evidently, many hardcore aficionados of intimate computing think of their collection of gadgets as so many warring tribes. The same person may own a cell phone, a laptop, a desktop, a Blackberry, a digital camera, and a printer. The media adapter was developed as a specialized Wi-Fi (802.11)-based solution, but of course media adapters/media extenders are confined to interface between television or stereo equipment (on the one hand) and computers/PDA's. A common headache for owners of multiple PDA's and/or computers is integrating different calendars, uploading info to databases from different points of input, and so on.

The Special Interest Group for the standard decided to name it after Harald "Bluetooth" Gormson, a king of Denmark who had united many rival Viking states. No doubt the mistranslation of "Blåtand" as "Bluetooth" was the arresting detail that made it the winning nickname.1 Electronic components need to have the microchip transmitter/receiver embedded in them. Bluetooth wireless connections are limited to a range of 10 meters, and the 2.45 GHz frequency (just slightly higher than most Wi-Fi). The volume of data transmission is much lower than Wi-Fi: 2 Mbps, sufficient for multiple-channel audio transmissions.

The most common application of Bluetooth is for hands-free cell phone headsets, but Bluetooth was intended to bypass all data cables, particularly USB cables. Bluetooth "networks" require no setup: the devices merely have to be in physical range and on the same channel, and there can be a maximum of eight devices involved. One device is a master, and the others are all "invited" to join the network as "slaves."

While Wi-Fi architecture is dominated by multiplexing concerns, Bluetooth is not. That's because in a Bluetooth network, there is only one master communicating with individual slaves, one at a time. The modulation involves frequnecy jumping at 1,600 cchannel shifts per second, sharply reducing any risk of interference (including interference with Wi-Fi networks).

1 "Bluetooth Overview," SearchMobileComputing.com (15 Feb 2006).
In 1994 Ericsson Mobile Communications initiated a study to investigate the feasibility of a low-power low-cost radio interface between mobile phones and their accessories. In Feb 1998, five companies Ericsson, Nokia, IBM, Toshiba and Intel formed a Special Interest Group (SIG). The group contained the necessary business sector members - two market leaders in mobile telephony, two market leaders in laptop computing and a market leader in digital signal processing technology.
Korak Dasgupta, "Bluetooth Protocol and Security Architecture Review," part 4

Additional Reading & Sources

"Bluetooth Overview," SearchMobileComputing.com (15 Feb 2006)

"IEEE 802.15 and Bluetooth: WPAN Communications" www.NetworkDictionary.com (2008)

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10 April 2007


Developed by Bob Metcalfe at Xerox's Palo Alto Research Center (PARC) in the 1970's for supporting local area networks (LANs), Ethernet was part of a large raft of information technologies that emerged that year.* It is both a cable/socket design, and a digital data transmission format.

The most familiar form is the "fat telephone" or 8-wire RJ45 cable (see figure). There is also something called "industrial ethernet," which are really just extremely high bandwidth (>10 megabits per second-Mbps) Internet connections, not true Ethernet at all.

In order to understand the concept of Ethernet, it's necessary to mention the 7-layer OSI Reference Model.

The OSI Reference Model
(OSI article)

The OSI specifies how data from an application in one computer moves through a network medium to an application running on another computer. The 7 layers are organized as media(1-physical, 2-data link, 3-network, 4-transport) and host(5-session, 6-presentation, 7-application). Media, here, refers to the mode by which data is transmitted over distance; e.g., over microwaves, coaxial cable, and so on. Host, here, refers to any computer on a network that is capable of running applications. All devices on a network, regardless of capability or description, are called nodes. (Nowadays, cases of the node that can't run a program are rare; they include dumb terminals). So the "host layers" are responsible for the final communications between the network and the application (such as a web browser).

The physical layer includes the specs for cables and routers. The data link layer consists of the precise format for encoding data for transmission. The data layer for the TCP/IP suite is where the Ethernet format resides. The connection between the two formats lies in the signal frequency. Ethernet requires cables that support a range of frequencies, which creates very demanding performance requirements for cable and especially connectors. The interaction between Ethernet (the data format) and the network format takes the form of Ethernet II Framing. In the Ethernet format, each packet is an IEEE 802.3 frame, which specifies the format, content, and size of each packet. Each frame consists of the destination and originating MAC address (6 bytes each), followed by a 2-byte sequence that gives the length of the frame. The frame has to be between 64 and 1518 bytes in length. There is also a frame check sequence (FCS) that is used to check the integrity of the frame; this occurs at the end of the frame.

Inside that package, there is a logical link control (LLC) that communicates to the network interface card (NIC) the memory buffer from where the frame came, and where it goes. This allows the same NIC to support multiple network protocols concurrently. Frequently LLC and MAC addresses are regarded as two different sub-layers within level 2 [*].

The next layer up is the network layer ("Internet layer"); this is the format that describes the actual network structure. In addition to the Internet Protocol (IP) , there are also several mostly-defunct networking protocols like SNA, token ring, and so on. The difference between networking protocols, in the least abstract sense, is the routing decision. In IP, routing goes "outbound" to a router, then to another router, and eventually to the correct host. In a token ring (to take an alternative concept), a packet is routed to the next host on the "ring," along with the "token."

IP is the component of the Internet suite that resides at the network layer (3); it reads the MAC address and uses it to route the packet in accordance with the network architecture. Part of the technical difficulty posed by IP is that it addresses a network of networks. Hence, a frame is likely to pass through many routers as it goes from network to network. The part of the network that an individual router is connected to is called a subnet; each node in the network is connected to a router within the subnet. The level 3 IP address directs the packet/frame to the correct subnet, but requires the address resolution protocol (ARP) to convert the IP address to the correct (layer 2) MAC address.

Peculiarities of Ethernet
Ethernet is an architecture used for local area networks (LANs). The physical component of Ethernet—its radio frequency (RF) transmissions and high signal density meant that data loss and distortion became a serious problem if network segments exceeded 75 meters. That limitation has been pushed back to tens of kilometers, so that college campuses and even major cities may be connected by the extremely high bandwidth LANs Ethernet allows. At the same time, transmission rates for Ethernet are now approaching 10 billion bits per second (Gbps).

Ethernet allows the transmission of data along circuits with many nodes on each circuit. This means that all the different nodes on a circuit will receive all of the data transmitted down the circuit, but each NIC will be able to select only the data addressed (illustration). Another important aspect of the Ethernet protocol is that it is decentralized; hence, all hosts on the network must follow uniform rules such that there is no crosstalk (CSMA/CD protocol). This allows Ethernet to support a very large number of possible network architectures.
* Another was the C programming language; in '73, the Unix kernel was rewritten in C, which may be said to be the true birthday of that operating system. Also, the TCP/IP specification was developed and formalized that year, beginning the Internet. Yet another event was the release—also by Xerox PARC—of the Alto, which pioneered the graphical user interface (GUI) and the mouse.

Cables: Ethernet and "industrial ethernet" (notice the capitalization) have been routed over several types of cables. As I've mentioned, the most familiar is the RJ45 (EIA/TIA Category 5E twisted four-pair) ,which looks like a fat telephone jack. This has 8 wires, compared to the 2 in a phone jack.

Another cable design is the coaxial cable most commonly used for cable television. Ethernet versions of this are distinguished by the slightly different connector; while coaxial TV cable has a C connector, cable Ethernet uses the BNC connector. Usage has greatly diminished in recent years. (SOURCE: Edward F. Kuester, "Common Coaxial Connectors") The BNC/coaxial system is similar in appearance to the M12 connector, which is being marketed as a new industrial ethernet format.

A third format is the SC/SC Duplex, a type of fiber optic industrial ethernet connector. Industrial ethernet standards such as these are semi-standard or proprietary extensions of the Ethernet (IEEE 802.3) standard; they are intended to allow very high-bandwidth (>10 million bits per second) LAN media in an environment that may be very harsh to electronic components. (SOURCE: Emcore, Inc., " Fiber Optic Connectors")

Routers: a computer networking device that links nodes in a network, and routes transmissions among them. Routers vary immensely base on the networking format used and the physical mode (coaxial, fiber optic, RJ 4-pair twisted) used; however, all routers do basically the same job. Based on the data supplied by the frame, the router can identify where it must logically dispatch each data packet. Through a succession of logical branches, the frame will eventually reach the correct destination. (SOURCE: Wikipedia)
ADDITIONAL READING & SOURCES: Howstuffworks, "How Ethernet Works"; AutomationWorld, "Getting physical with industrial ethernet"; Cisco Systems, "Internetworking Basics"; very odd but entertaining explanation may be found at RouterGod ,"Robert Downey Jr. on the IEEE 802.3 Ethernet Frame"—this was the one coherent explanation I could find that incorporated a reference to a voluptuous sheriff's deputy and scented body lotions. See also "CCNA Bootcamp: the OSI Model";

Wikipedia: OSI Reference Model, Ethernet, Ethernet II Framing;