On The Margins

Monday July 04, 2005

[ Networks ] From Tehran With 50.6 KBPS

On this holiday of mine in Tehran, I am reminded how large numbers of people still live with 50.6 kbps. (Don't forget that until a few months ago, more than 1/2 of the Internet users in the U.S. also depended on dial-up networking although their number is fast dwindling.)

Don't get me wrong. There are now many who have xDSL connection in Tehran. Local companies such as Pars-Online offer it but they seem to have exhausted their Local Loop Office capacity. (I called this morning to equip where I'm staying for a month but there was no extra capacity to be devoted to that. Pars-Online, for example, allows such installations to be disconnected after a month.)

Oh well . . . I now sit behind a Pars-Online dial-up network as I write this short blog. This afternoon, I called their office and got two "Internet cards," each worth about $7.50, and each giving me 20 hours of connectivity, delivered to my door-step.

In the meantime, in Tehran, I have had a chance to visit my grand-mother and stay at her house for a couple of days, go to Darband for a hike in the mountains and plan to go to the top of Mount Tochal as height preparation before climbing Mount Sabalan, again, in a couple of weeks. I did this last year but repeating it is not boring at all. I think it is great exercise and a good confidence-building measure for climbing other mountains. It all depends on who else joins you. A few extended family members have already volunteered to join me for Sabalan. It is just high enough and just long enough with which to measure one's endurance. I would also like to go on a partial climb of Mount Damavand if time allows.

2005-07-04 12:38:22.0 -- ; Permalink ; Trackback.

Thursday June 02, 2005

[ Networks ] Dial-up Still Alive in The U.S.

I was surprised to read in The Financial Times today, that of the 80 million U.S. Internet subscribers, more than half still use dial-up access.

Internet, Dial-up, Broadband.

2005-06-02 12:21:30.0 -- Comments [0] ; Permalink ; Trackback.

Wednesday June 01, 2005

[ Networks ] Banks Fight Phishing And Ken Releases A New Book

Banks have begun fighting phishing.

For example, The Wall Street Journal is reporting that Bank of America will be requiring account holders to register a unique image with their online accounts. On subsequent visits, the image is displayed prior to the user entering his or her (or its?) password. Frequently used machines have to be "registered" (through cookies and IP addresses) with the online banking service for this to work. If an "unknown" computer is used, a challenge question will be posed.

But does that totally eliminate "phishing" or does it simply reduce it to some very acceptable levels?

First of all, it is clear that these techniques will reduce "phishing" appreciably. Since the bank has something you've left in its trust (the digital image), the "phisher" cannot "phish" for you unless the "phisher" knows what you've left in the bank's trust, i.e. the image. (So, even after the challenge question is answered, you should expect to see the image you left in the Bank's trust.) Now, to "phish," the "phisher" will not only have to "phish" for you but it also needs to break the security of the connection you have with the bank or masquerade as the bank during your picture registration. The problem for the "phisher" becomes rather complex, but have we really eliminated all possibilities? (The answer, obviously, is negative, but that depends, at least theoretically speaking, on an application of temporal logic, and we don't really want to get into that right now.)

Note that the sort of measure that Bank of America has taken is really the right way to fight this sort of "failure" or problem. The trouble is that one finds and must be prepared, theoretically speaking, for a need to change the technique on a continuous basis and in the long run. (The particular technique we just discussed above can be quite robust as a response.)

What does all this mean?

To really understand the the associated problems, one needs to look at failure theory in distributed systems software. In other words, if we consider "phishing" as a failure, theory of failure in systems can become applicable.

A good reference on this failure view of cyber-hostility is Ken Birman's Building Secure and Reliable Network Applications. While we're on this topic, I should note that Ken has just released a new book.

One other point—as it becomes more and more complex to sign on for high-value on-line services (some are now using token cards to achieve what Bank of America is attempting to achieve with the trusted image technique), isn't it time for us to think even more seriously about single-sign-on to networks? Or does it become necessary to carry many token cards in the hand, as we carry credit cards, building badges, driver licenses and other identity tokens in our wallets and purses?

Phishing, Failure.

2005-06-01 18:55:31.0 -- Comments [1] ; Permalink ; Trackback.

Monday May 16, 2005

[ Networks ] Recent Study on Online Computer Games

This morning, my daughter demonstrated to me what she had been telling me over the weekend. She pulled up an eBay page of running auctions of virtual Runescape game assets. On the first page, one virtual asset was selling for more than $1000. Other items were listed in British Pound and in Australian Dollars.

There has been a lot of news on such auctions. Surely, these may never become as revenue generating as the spectrum auctions but they do deserve thorough study. I recently wrote a little entry about the auction of virtual gaming assets, and this morning, a recent entry on professor Lawrence Lessig's blog drew my attention to a study by OECD's Working Party on Information Economy, released on May 12, 2005 and exploring the economics and cultural ramifications of online computer and video game industry.

Here's the first paragraph of the report. For more, go to the original, which is available for free.

Computer and video games is a young industry with rapid growth underpinned by technological development. The global market in 2003 was estimated to be over USD 21 billion compared with USD 32 billion for the recorded music industry; US games revenue in 2001 surpassed film box office ticket sales. The main segments in 2003 were the console off-line (73%) and PC-offline markets (17%). Online and wireless games are still relatively small (6.4 and 3.4% respectively). However, there is a trend towards online games in PCs and consoles. New games are released with some online capabilities, and it is expected that nearly all will become at least in part online. Computer games are R&D and innovationintensive and games programming and design are highly skilled occupations. Market expansion is coming through development of online network technology, diversifying content and developing large-scale online games. The industry is also increasingly seen as strategic by major media, Internet and consumer electronics firms.

In the meantime, it is worth nothing that OECD's Working Party on Information Economy has also conducted a whole series of other related studies on digital content.

OECD study does seem to miss the important trend in online game communities I mentioned at the beginning of this entry—i.e., the auctioning of virtual game assets. In fact, it may have been worth noting that some online games, such as Runescape, seem to have been designed to enable exchange of virtual assets. Such ability to exchange unleashes all that comes with it, including real auctions performed with real money.

Online Games, Economics, Virtual Assets, Auctions.

2005-05-16 11:34:48.0 -- Comments [3] ; Permalink ; Trackback.

Wednesday April 20, 2005

[ Networks ] Sony's Station Exchange Auction Site for Vitual Game Property

Even children are already engaged in exchange of virtual game property by agreement among friends or by stealth when facing foes.

Nick Wingfield of The Wall Street Journal, is reporting on Sony's announcement today that it will launch its Station Exchange auction site for purchase and exchange of virtual game properties.

According to Edward Castronova, a telecommunications professor at Indiana University, the value of global trade in virtual property can be at more than $100 million a year, writes Wingfield.

Sony Online Entertainment's John Smedley says that Sony has been wanting to avoid the "the rich-own-the-game mentality" but he "estimates that about 40% of current inquiries to the publisher's customer service department are the result of such deals on other sites going awry," Winfield rerpots. "It's a customer service nightmare," according to Smedley.

Sony plans to stratify players based on whether they have obtain virtual game properties through its auctions.

This is the first formalized way I know where players can actually make money playing electronic games. What does that mean?

Games, Virtual, Property, Sony, Auction.

2005-04-20 17:09:53.0 -- Comments [1] ; Permalink ; Trackback.

[ Networks ] Immutability and Mobility in Knoweldge Media

All knowledge media (e.g. books, lectures, apprenticeships, movies, newspapers, digital and multimedia documents, weblogs, laws carved in stone, laws entombed in volumes preserved in libraries) can be categorized along "mobility" and "immutability" dimensions. While some media (such as digital, multi-media documents) provide for great mobility, our reliance on their immutability proves sketchier than our trust in the immutability of physical, paper documents. When my paper arrives at my door every morning, I'm quite certain it was not changed between the moment of publication and delivery. What matters in determining the stability of a given knowledge media is the balance it strikes between immutability and mobility. Hammurabi's Laws, carved on stone, have certainly demonstrated how immutable and lasting, through time, they can remain. (See also Iraq Museum International.) On the other hand, many corporate workers have (mobile) access to their e-mails almost everywhere but different corporations institute varying policies regarding the length of time or the amount of space (or both) they will allow for archiving of e-mails. If a corporate policy says that e-mails beyond a certain time (or space) are going to be discarded, we actually have to reconstruct our worlds periodically over large time intervals to determine what to keep and what not to in order to increase their chance of survival. While much important material is now exchanged through e-mails, it is highly unlikely that all important e-mails will survive or that we will have a reliable, social aptitude for determining what digital document deserves replication into the future. The decision will be made, often, by programs. Physical letters that matter, on the other hand, prove easier to identify and will probably have a better chance of surviving through hundreds of years. Their physical form already speaks volumes to their importance. (What sort of paper was used? Who was writing to whom? What sort of ink did they use? What sort of pen?) One can argue that they can even be "found" more easily because as time passes, their existance gives evidence to their importance. In an electronic archive, on the other hand, the degree of a document's importance remains quite hard to determine, particularly because of the lack of context that a physical object carries with itself.

Media, Knowledge, Code, Immutability, Mobility, Paper, Hammurabi, Law.

2005-04-20 11:42:34.0 -- Comments [1] ; Permalink ; Trackback.

Thursday February 24, 2005

[ Networks ] China and IP Addresses

A 2001 IPTel tutorial on SIP (Session Initiation Protocol) notes how China has less IPv4 addresses than Stanford University! (Back then, when they divided the numbers, I guess, China was still considered an "enemy"!?) A 2003 report published in People's Daily expands on the problem. For example, it notes that: The present Internet is based on IPv4 protocol. Meanwhile, since the Internet originated in the US, the country has much advantage in IP address distribution. Among the world total of 4 billion IP addresses, 74 percent went to the US itself while the European and Asia-Pacific countries, as latecomers, could only share the rest 26 percent of leftovers. China, in particular, suffers serious IP address shortage. Statistics show that currently the nation has more than 60 million Internet users, but only a total of 30 million-odd IP addresses are available, namely two users sharing one address. Meanwhile, the nation's 240 million mobile phone users are turning into potential Internet surfers and they need their own IP addresses too. The inadequate supply of IP address is becoming a bottleneck for the Internet development in the country.

The report goes on to emphasize the importance of IPv6 to China and points to large trial networks in Chongqing. It may be time to check back on some of the trends and predictions of the report.

Networking, China, IPv4, IPv6

2005-02-24 14:23:35.0 -- Comments [4] ; Permalink ; Trackback.

Sunday February 13, 2005

[ Networks ] Service Dependencies

The idea that network services should act independently of each other has proven to be a very sound one but more and more dependencies continue to creap into the urban system's network services. When the electricity goes out, we do not expect out water to stop too. A curious development in U.S. homes has effectively caused a great deal of interdependence between electric power service and wireline communications network: The phone line of most homes is connected to a wireless home phone base which is electrically powered.

When the electricity goes out, there is no wireline phone service unless the home is equiped with an old-fashioned rotary phone or a simple digital phone powered by the phone lines from the central office.

We usually overlook this simple dependency in the U.S. because power outages are so rare. They do happen, though, and often at the worst time, for example, when you're home alone with a bad case of flu. My home was among 26 affected by a power outage from early morning until late afternoon this past Friday. Not only was I unable to receive or place calls from my home phone (yes, my mobile did work and had been charged the night before), the DSL was also out rendering my laptop (and Skype installed on it) useless even if it had a good amount of power left in its batteries. (In my case, I could neither make tea nor warm any soup for lunch.)

Of course the phone network continues to operate regardless of power outages. The dependency is at the outermost endpoints of this network and the electric network. Since most people are equiped with mobile phones, and since those older consumers who stay away from them usually have some rotary phone at home, the dependency may not be as disasaterous as it first sounds.

Telecommunications, Technology

2005-02-13 16:29:42.0 -- ; Permalink ; Trackback.

Monday February 07, 2005

[ Networks ] Epidemics of Opinions

In a recent academic paper (Fang Wu and Bernardo Huberman, 2004, "Social Structure and Opinion Formation") on the spread of opinions, we read.

Our theory further predicts that a relatively small number of individuals with high social ranks can have a larger effect on opinion formation than individuals with low rank. By high rank we mean people with a large number of social connections. This explains naturally a fragility phenomenon frequently noted within societies, whereby an opinion that seems to be held by a rather large group of people can become nearly extinct in a very short time, a mechanism that is at the heart of fads.

In other words, opinions held by low social rank individuals, even if widespread will suffer extinction much more quickly than opinions held by a few individuals of high social rank.

This says nothing about quality of such opinions. The actual model through which opinions are propagated is a different matter all together.

Society, Networks

2005-02-07 15:31:25.0 -- ; Permalink ; Trackback.

Thursday January 27, 2005

[ Networks ] A Can of Worms for the Mobile Terminal

The Brazilian tinkerer, Marcus Velasco, has helped prove in practice how dangerous worms can travel from mobile phone to mobile phone on the back of Bluetooth.

2005-01-27 06:19:04.0 -- Comments [0] ; Permalink ; Trackback.

Tuesday January 18, 2005

[ Networks ] Phishing on the Rise

Brian Krebs of The Washington Post reports an alarming rise in phishing, "the use of official-looking e-mails and Web pages to trick people into divulging financial information."

Apparently, the number of incidents quadrupled from August to November of last year.

This new online fraud has very low start-up costs and high returns. At least for now, "a continued increase in phishing activity is all but certain," reports Krebs.

The advance in phishing has gotten to a point where one can find "software that help users automate the design and deployment of their scams." A great deal of ill-gotten information seems to be moving through "carder" IRC channels.

Honeynet Project, a volunteer security research organization that studies new trends in Internet crime, provides valuable resource for further study and engagement.

2005-01-18 10:16:00.0 -- Comments [0] ; Permalink ; Trackback.

Wednesday January 12, 2005

[ Networks ] Sentence Handed Down in the Largest Identity Theft Case in the U.S. History

In a networked world where most transactions are disembodied, identity theft becomes a concern for every identity and privacy expert.

The Dow Jones Newswire reports the sentencing of a Cartersville, Georgia, man involved in the largest identity theft case in the U.S. history. According to the report, "more than 30,000 people were victims of the scheme, in which credit reports with stolen passwords were downloaded from three major credit-reporting agencies and sold to street criminals for $60 each." The prosecutors of the case put the financial loss to victims, including banks and credit-card companies, at $50 million.

A light sentence of 14 years in prison and 3 years of supervised release was handed down. The 35-year-old culprit, a computer technician who used to work for credit reporting companies, attended the court with an oxygen mask and in need of a heart transplant.

2005-01-12 12:25:53.0 -- Comments [0] ; Permalink ; Trackback.

Wednesday January 05, 2005

[ Networks ] OMA DRM for a Fee

Reuters is reporting that handset vendors will be paying $1.0 a device to a syndicate of patent-holders in order to include OMA DRM 1.0 in their devices. (OMA stands for the Open Mobile Alliance.)

Handset makers will pay $1 to include OMA's Digital Rights Management (DRM) 1.0 standard into a mobile phone. Content owners which want to protect their material with OMA DRM, will pay royalties representing one percent of the consumer selling price of their service.

The five companies are InterTrust and ContentGuard, two very small but powerful DRM companies, plus consumer electronics giants Sony Corp and Matsushita Electric Industrial Co Ltd from Japan, and Dutch Philips Electronics.

The pooling [of patents] should also make clear that everyone who uses OMA's DRM needs to pay royalties. ContentGuard told Reuters in October that OMA had not informed its members properly and that many handset makers thought the anti-piracy standard was free.

This story does not have a byline, and I've seen Reuters pull stories out or make them unavailble, sometimes right after publishing them.

2005-01-05 22:34:16.0 -- ; Permalink ; Trackback.

[ Networks ] When to Use Content Indirection

When is it O.K. to use "content indirection"?

Let's first explain what "content indirection" means.

You are sending a message to a peer, and you point your peer to another place to get some part of the message. This type of pointing (perhaps, through a HTTP URI) is usually referred to as "content indirection".

One uses content indirection when one wants to avoid processing on the network (by routers, proxies, gateways, user agents, etc.) of optional parts of messages which could be obtained from some other place if needed, when one wants to preserve a certain limit on the original message size, when one wants to shift content forwarding (or download) from the protocol of the original message (e.g. UDP) to some other protocol (e.g. HTTP) or when one wants to have some kind of static control over the "indirected" content.

Like everything else in engineering, there are no golden rules and there are many trade-offs.

2005-01-05 19:06:19.0 -- ; Permalink ; Trackback.

Thursday December 23, 2004

[ Networks ] re-INVITE or UPDATE in SIP

In the Session Initiation Protocol (SIP RFC 3261), there are two request types that can be used to modify a session. One of them is called an INVITE (or re-INVITE) and the other is called UPDATE.

So, for example, if you're on your PDA, you'll probably stay on your PDA and will not be prompted to take any action when UPDATE is received. However, if user wants to make a substantial change to the Session, say add video streaming, a re-INVITE needs to be issued on the same session. You'll be prompted and asked whether you'd like to accept.

In summary, UPDATE is used to modify ongoing session and no interaction with the user is stipulated on the receiving end of the request. On the other hand, when re-INVITE is used, some sort of interaction with the callee follows.

2004-12-23 17:07:46.0 -- Comments [0] ; Permalink ; Trackback.

[ Networks ] SIP-ing Santa

Request:

INVITE sip:Santa.Claus@NorthPole.int SIP/2.0
. . .

Response:

SIP/2.0 180 Ringing Raymond
. . .

Session Initiation Protocol (SIP, RFC 3261) messages are text-based. They include a start line, like the ones above, followed by a number of required and optional header fields in the form of name-value pairs, x=y, an empty line and an optional messsage body. The message body can be composed of anything, including multi-part bodies using MIME (Multipurpose Internet Mail Extensions, RFC 2045) encoding.

2004-12-23 11:34:57.0 -- Comments [0] ; Permalink ; Trackback.

Tuesday December 14, 2004

[ Networks ] WLAN and 3G

Earlier, I've written about the interplay of WiFi and cellular networking, looking at various contexts. The relatioship between these two different modes of networking has significance for device vendors, network equipment providers, operators and consumers.

Device vendors look to bring devices that can be endpoints in both types of networks, NEPs want to apply their cellular and mobile network expertise to Wireless LAN (WLAN), operators are trying to better understand the business model and be open and willing to provide better and more integrated service across both networks, and subscribers want good, seamless service with predictable behavior on both.

WiFi (.5 to 1 Megabits) and 3G (.1 to .5 Megabits) networks will likely remain good compliments of each other for some time to come, The Wall Street Journal¹ reports. This trend is also evidenced by what operators as well as the network equipment providers have done in the last couple of years.

For example, "T-Mobile, a unit of Germany's Deutsche Telekom AG, recently signed a so-called roaming agreement with BT Group PLC of London. Customers of either company can now use 10,500 hot spots in hundreds of cities and towns in Europe and the U.S. Meanwhile, BT recently announced new roaming agreements that give its customers access to 20,000 Wi-Fi hot spots across 11 countries."¹

What is of greater interest remains how to better take advantage of parallel deployments of cellular and WLAN networks.

This challenge will have to be answered by those who have developed great expertise in the area of cellular networks, say, for example, Ericsson. One of Ericsson's important areas of core competence, in my opinion, covers cell-to-cell handoff as well as roaming across public land mobile networks². It should be a very easy move by Ericsson to bring those competencies to WLAN networks. It should literally be just a matter of deciding to do it.

This Monday, for example, Ericsson announced it has joined the WiMax Forum: "WiMAX ensures interoperability of the open IEEE 802.16 standard for broadband wireless access. It is a natural part of an operator's Ethernet broadband offering and can also serve as transmission backhaul," said Karl Thedeen, vice president, product area wireline at Ericsson.

[1] See here, for The WSJ report published on December 13, 2004. Registration, subscription or 1-time-payment may be necessary depending on time and mode of access to Dow Jones publications such as The Wall Street Journal.
[2] See Gunnar Heine's excellent book GSM Networks: Protocols, Terminology, and Implementation on hand-off and roaming in GSM networks.

2004-12-14 22:44:42.0 -- ; Permalink ; Trackback.

Monday December 13, 2004

[ Networks ] Network Power

David Bollier is certainly a capable writer of the results of the gatherings at the Aspen Institute (also in Berlin). In People, Networks, Power: Communications Technology and the New International Politics, he reports from the 12th Annual Aspen Institute Roundtable on Information Technology. John Seely Brown is one of the commentators The report points to several recent books which "explore the properties of emergent networked organizations": Smart Mobs, by Howard Rheingold (2003) Linked: The New Science of Networks, by physicist Albert Laszlo Barabasi (2002) Six Degrees: The Science of a Connected Age, by Duncan J. Watts (2003)

To this list, I would have added, for complementarity from a different perspective, Being There by Andy Clark. Hubert Dreyfus had me read this while I was studying philosophy of artificial intelligence with him. There're some good chapters on the concept of scaffolded intelligence, where embeddedness in environment and organization is explored as a source of intelligence and coping. While still from the perspective of cognitive science, Clark sheds some fresh light by emphasizing social modes of behavior and intelligence. His greatest contribution, I believe, was to bring to attention the importance of the outside world (as opposed to the inside world, if there's one) to intelligent behavior.

There is also the aspect of hierarchy vs. networks which is worth mentioning. Some believe that networks and hierarchies stand on opposing poles. However, in People, Networks, Power, Bollier quotes John Kunzweiler, a partner at Accenture, who notes that even in the ultimate open networks such as eBay^[1], about 80 percent of the dollar value of things sold is sold by about one to two percent of the sellers. Kunzweiler gives this example to emphasize that "networks make the influence of hierarchies much more subtle--and in a lot of ways, far more powerful than explicit or overt hierarchies." This is certainly an interesting point worth exploring further.

[1] Here, "network" is primarily a network of users, emphasizing the role of the endpoints connected through the network rather than the protocols and equipment involved.

2004-12-13 16:33:14.0 -- Comments [2] ; Permalink ; Trackback.

Wednesday November 17, 2004

[ Networks ] Battery Life

In the United States, near my home city in California, I have to charge my Sidekick II phone about thrice a week. Here, in Barcelona, I've only had to charge my Sidekick II once in four days. How's that possible? Has my battery improved its efficiency? Not really.

The answer may lie in the existence of better radio network coverage, offered by Movistar to my Sidekick II, which is a tri-band GSM/GPRS phone. Or it may lie in the fact that I've not used it as much to talk and more to send and receive messages and e-mail. In any case, it's interesting to think about how radio network configuration and availability affects battery consumption in mobile stations.

Power usage on a network must tightly relate to availability and distribution of connection points. For example, see this presentation.

I'm sure some people have already considered how to gain aggregate power savings by means of relay among mobile stations themselves. This will probably improve aggregate power usage at the expense of power usage on phones closer to the tower. Discussion of this hypothesis regarding aggregate power advantage at the expense of some members of a mobile cell seems like great material for academic research.

2004-11-17 04:07:21.0 -- ; Permalink ; Trackback.

Sunday November 14, 2004

[ Networks ] Mobile in Munich

The aiport wireless LAN works really well here in Munich.

I was able to connect through the VPN, read and write back e-mail on one of our NEP partners, do this blog and watch German and English news on a large flat panel screen, all in very comfortable, non-VIP, and tobacco free (!) zone, right here at the G gates in terminal 2. It was certainly worth the few Euros paid for it, and was very helpful given the fact that I had to recover the name of the hotel where I'll be staying.

2004-11-14 09:13:24.0 -- ; Permalink ; Trackback.