On December 17th, Google Korea announced it will provide free WiFi at almost every Starbucks in Korea, and I tried to use it yesterday. As you might know, Google has a market share of only 4 percent in Korea. So this promotion aims to increase its market share and lead Korean customers to iGoogle, which could be considered Google’s counterpart of Korean portals. After you successfully get an access to the network, you will be directed to the iGoogle page. You can also read the brochure explaining iGoogle at Starbucks.

However, to use the service, you need to verify your real name using the Korean Alien Registration number or the Foreigner number. The promotion brochure is co-written in English for foreigners, but actually they can’t use it.

In addition to that, yesterday, I couldn’t use the service on any other browser other than Internet Explorer. When I first opened a browser, I could see a very similar page on any browser like the below. On Internet Explorer, I could also see a checkbox saying ‘Set iGoogle as your homepage’.

However, when I clicked the ‘Access Free Internet’ button, there was no response on any browser except Internet Explorer. Even on Google Chrome, it’s not possible to get a response. The reason seemed to be a simple Javascript error.

Of course, it had been serviced properly on Google Chrome, and the problem seemed to be a temporal issue while modifying the page. It might be my own problem. But why this sort of things happen? Might the modified page be tested only on Internet Explorer? I hope not. But if there are pages developed like this, it’s still hard for Korean people to get rid of Internet Explorer. To save the developer, the developer must also try to survive by herself.

In the enterprise environment where agility and reusability are very important assets, SOA has been the most prevalent paradigm for last several years. But contrary to the expectation, the skepticism about ROI and the complexity of implementation have prevented the proliferation of SOA. Finally, people have chosen “Web” services not Web “Services”.

Web-Oriented Architecture

In 2005, Nick Gall from Gartner coined the term WOA (Web-Oriented Architecture) to describe Web-based SOA.

WOA = SOA + WWW + REST

However without any official definition or clear consensus about the meaning, there were lots of discussion about the term. Dion Hichcliffe and other experts tried to define the meaning of WOA, but there was a slight difference between their opinions. After all, on November 11, Gartner published an official note about WOA.

WOA is an architectural substyle of SOA that integrates systems and users via a web of globally linked hypermedia based on the architecture of the Web. This architecture emphasizes generality of interfaces (UIs and APIs) to achieve global network effects through five fundamental generic interface constraints:

1. Identification of resources
2. Manipulation of resources through representations
3. Self-descriptive messages
4. Hypermedia as the engine of application state
5. Application neutrality

Like the author said, the first four of the five interface constraints of WOA are the same as REST’s uniform interface constraints. However the last one Application neutrality has been newly added.

Application Neutraility

One of the most important goals of SOA is to maximize reusability, which means achieving better scalability. Scalable systems can be built using middle out architecture.

Middle out architecture is neither top down nor bottom up method. It’s the way to design an abstract interface at the center first and then expand it to the top and bottom. The interface called IFaP is an abstract combination of Identifier standard, Format standard, and Protocol standard.

A representative example of middle out architecture is the Internet. The interface of the Internet consists of IP address, IP packet, and IP protocol, and each respectively plays the role of Identifier, Format, and Protocol. Based on the interface, the Internet has been expanded to the diverse applications including Web and VoIP, and the several new platforms like Linux, successfully providing stable services.^[1]

Application neutrality of WOA is also about IFaP. A fundamental characteristic of the Web is serendipitous reuse, highlighted by Tim Berners-Lee and Roy T. Fielding. Serendipitous reuse can be achieved by general and application neutral interfaces. In other words, the more application neutral a interface is, the more reusable it is.

• “Unexpected reuse is the value of the Web” (Tim Berners-Lee)
• “Engineer for serendipity” (Roy T. Fielding)

However, WS-* standards more focus on implementation neutrality than application neutrality, says the author. Implementation neutrality of WS-* standards can help support various middleware technologies, but application neutrality plays more significant role in creating powerful network effects. So, WOA strongly emphasizes application neutrality.

Application neutrality should be the principal goal of an interface, and implementation neutrality should be a secondary goal.

How Neutral?

At Jazoon’07, Roy T. Fielding said SOA is null architectural style which has no constraints at all. But WOA has at least the 4 different uniform interface constraints of REST. The issue is the last 5th constraint, application neutrality.

The author insists application neutrality is an implicit constrtaint in REST, and every interface element should be defined as generic as possible.

Don’t just build on generic interfaces; build up generic interfaces that are only slightly less generic than those built on.

However, how generic does it need to be? What is the basis for determining if an interface is generic? If going from neutral to specific is a continuum, how granular will it be?

For engineers to understand and adopt WOA correctly, and to build practical systems based on it, the questions above may need to be answered clearly.

1. CSTB and NRC, The Internet’s Coming of Age, National Academies Press, 2001, p. 128.

I like coffee very much, so I go to a coffee shop almost everyday. When I decide which coffee shop to go, the first thing I consider is of course the taste of coffee. But the second most important thing is Wi-Fi access. Nowadays almost every coffee shop provides Wi-Fi access for free. So I don’t have to worry about it anymore. However, I feel everyday that most coffee shops use the default settings for their network names. The most famous name in Korea, iptime is also one of the product names and the default setting of it.

Holland-based CoffeeCompany uses the network names to sell cups of coffee. More precisely, they use their menu items or today’s special as their network names, such as ‘OrderAnotherCoffeeAlready’ or ‘BuyaLargeLatterGetBrownieForFree’. What a brilliant idea! It could be possible for people who order a cup of coffee and stay for a whole day, or sit down on a bench and steal internet access to buy one more cup of coffee. Even someone could encourage himself to talk to the girl over there after seeing the network name, ‘BuyCoffeeForCuteGirlOverThere’.

There is more. A German car rental company tried to attract customers in the same way. The blogger who introduced the company called this kind of marketing ‘Wifitising’, which is a combination word of ‘Wi-Fi’ and ‘advertising’.

Of course this method can’t prevent people trying to steal internet connection without charge. But, it doesn’t require any expenses, and it could make customers laugh. So there is no reason not to try. Now I have to change my network name to a funny one. Who knows? Maybe the pretty girl next door will give me something delicious. ;)

However, I have a few points I’d like to make.

1. Resource states and application states need to be explained separately.

   GET and HEAD are special cases since they don’t cause state transitions.

   As the above quote says, GET and HEAD don’t change any resource states. But they do cause application state transition. Think about Web browsers. When you click a link on the page, the Web browser will GET a representation of the resource pointed by the URI and move from one state to another. That’s exactly how you can see this page on your Web browser.

2. Everything you need to know is media type.

   <next/> tag in the article is primarily about hypermedia. The authors said the XML dialect used by Starbucks can embed information about another resource. However, IMHO, the only information that need to be embedded in that dialect is the identifier of the resource, such as URL.

   Here is where “Hypertext As The Engine Of Application State” comes into play. The next state has to be described by only a representation of the resource. A single resource can have multiple representations in different media types, each media type defines its own processing model, and every resource representation can be described by themselves (i.e., self-describing resource representations).

   So I don’t know why we need another namespace or a sort of standard for abstract state transitions. State transition is one of the basic notions of REST. Even if we have that namespace (like http://example.org/state-machine), we still need to define semantics of each type of transition in another namespace (like http://starbucks.example.org/payment). Furthermore, as long as the representation is self-described, we don’t need to set the rel attribute to the type of the representation in advance, because it can be derived by negotiation with the server. So, like the below, we can define a tag for a specific type of transition and its semantics can be defined by the tag itself. Then, we can re-use or standardize the namespace which defines that tag.

   <order xmlns="http://starbucks.example.org/">
     <drink>latte</drink>
     <additions>shot</additions>
     <cost>4.00</cost>
     <payment>https://starbucks.example.com/payment/order/1234</payment>
   </order>

3. The human Web is also RESTful.

   The consumer application – the Web browser – simply renders the HTML, and the state machine (that’s you!) follows links using GET and POST. In Web-based integration the same occurs, except the services and their consumers not only have to agree on the interaction protocols, but also on the format and semantics of the representations.

   I guess the above quote is in sort of contradiction to the following.

   In the human Web, consumers and services use HTML as a representation format. HTML has its own particular semantics, which are understood and adopted by all browsers.

   IMHO, in the human Web, the same occurs without any exceptions.

4. Some other comments…

   • I also think the use of PUT for partial updates is not a good idea. POST or PATCH seems a better option.
   • I wonder if using OPTIONS or Expect/Continue is always of benefit.
   • “URIs represent the transitions within a state machine.” is too simple and not accurate.
   • I think even if the resource is editable, there should be only one address for that resource.
   • We don’t need to use Microformats in XML. What about RDF?
   • I totally agree with the authors’ opinion about URI templates.
   • We have to understand the importance of evolution and partial understanding on the Web.

I guess the authors know very well everything that I mentioned above, but some newbies like me could be misled in some way. Anyway, this article is excellent and worth taking time to read.

But there is more. “E” allows you to integrate many social network services. If you add your Twitter account to “E”, you can be a follower of Twitter by typing the passcode on your phone. Now it supports only Twitter, PICNIC, and Soocial, but Delicious and Last.fm will be also added soon.

This is not the first one of its kind. In LIFT Asia 08 which was held in Jeju, Korea last September, A Switzerland-based start-up introduced a service called Poken. Poken is a similar service to “E” to exchange contact information, but they put more emphasis on off-line social networking. Poken uses small keychain shape USB devices rather than mobile phones. This device exchanges data with sparkling when two devices high-five. It’s more intuitive than using mobile phones. The device is a pretty aesthetic, and it would cost around $3 only. Poken is currently in closed-beta, but it’s enough to attract people.

The problem is the service I’ve explained “E” also have a plan to make that kind of device. That’s why it reminded me of Poken when I first read the description of “E”. The device called Connector of “E” is a bit bigger than Poken’s, but the metaphor, exchanging contact information by touching two devices together, is totally same. To use “E”, you don’t have to buy a Connector since you can use “E” on your mobile phone. It could lower the adoption barrier of “E” which is the biggest problem of Poken.

Both services have a similar business model. The success of both depends on the number of users and the popularization of the device. It’s sort of a typical service relying on network effects. The CIO of Poken David Brown who I met at LIFT Asia 08 said they could release their device at high-profile events, or they could change the design of the device to use it as a promotion product. “E” also tries to sponsor high-profile events to release their device. However, Both of them don’t have any clear business model except selling the device.

Poken has the ghost mode to get other’s contact information without showing yours. But it doesn’t differentiate Poken from “E”, rather “E” which can be used on mobile phones seems to have a bright prospect.

I have three invitations of “E” which is currently in closed-beta. If you need an invitation, please leave a comment. Twitter is the only service you can integrate with “E”. If you come to Open Web Asia ‘08 tomorrow or WebAppsCon 2008 next week, you can meet me and give “E” a shot. :)

Suppose all the information stored on computers everywhere were linked, I thought. Suppose I could program my computer to create a space in which anything could be linked to anything.^[2]

For a long time, actually many people have tried to transform information to knowledge through technical innovation, like the desire to fly.^[3] Now we finally have the space called “Web”.

It’s been almost 17 years since the Web became known in 1991.^[4] We need a lot more days to achieve what we’ve dreamed of, but we can see many changes. I guess when we have the “Web” that Tim Berners-Lee and other pioneers dreamed of is not that far from now.

Looking at the future of the Web that Tim Berners-Lee thought of in 1997, it looks like everything has progressed according to the plan. Since the beginning, we’ve wanted to make the Web a space in which anything can be linked to anything else, anyone can make a link, and a space we build together. Now we’re close to that dream in the name of “Web 2.0″. Not only documents but data are now roaming around the Web. The problem of trust is becoming a more important issue. More and more devices are being connected to the Web in the name of ubiquitous or mobile. Contrary to W3C’s wish, the Web could possibly be approaching to its full potential by itself. After all, the goal of the Web “Leading the Web to Its Full Potential” will be achieved by the people using it.

From now on, I’ll try to talk about the Web and its way toward its full potential on this blog. Since I haven’t wrote a post for a long time, it doesn’t seem so easy to restart blogging. But, I’ll try to keep this blog up. I hope this blog will go on for a long time and be worth reading. Stay tuned!

1. J. Greenberg et al., “Metadata: A Fundamental Component of the Semantic Web,” Bulletin of the American Society for Information Science and Technology, April/May 2003, pp.16-18.
2. T. Berners-Lee, Weaving the Web, HarperBusiness, 2000.
3. V. Bush, “As We May Think,” Atlantic, July 1945.
4. T. Berners-Lee, “World Wide Web: Summary,” alt.hypertext, August 1991.

I believe that ‘blog’ is the tool to connect people and the world, and to make who we are.

You can use a blog solely to record and archive information. However, blog is meant to be used for communication. Writing a post and publishing it is basically to expose ‘me‘ and to communicate with others. The posts that can gain attention give the information to the readers, and those readers give back attention and communication to the authors. These activities make the world we’ve lived in, so we can grow together in this world.

Now, I’m starting to communicate with you and to be us. Through this opportunity, I want to share something with you again and together.

Hello world! Hello blogger!