Common graph algorithms in computer science mostly assume that there’s no cycle in graph structure. On the other hand, the cyclic authentication proves to be a great tool for security enhancement indeed. A cycle means eternity. When a program meets the cycle, it never ends. We can apply the mechanism to ameliorate encryption algorithm. For instance, suppose that there are three individual services A, B and C. Service A has the password to access B, B has that of C and C has that of A. It’s a cyclic password lock. No one can break the cycle unless every service is completely exploited by attackers. Excluding social engineering cases, the countermeasure proves no way to break up. It’s a very subject worthy to consider.

We’ve researched a cloud database solution for a couple of months; the project name is Cloudbean. The project aims to bring a specially structured database solution which is scalable, high-performance distributed database system. The optimization process is now going on to make the solution faster than before. And now we unveil the result of performance test conducted recently. The Cloudbean version is not the newest that the upgrade and code migration are still in progress. The tested Cloudbean version is 1.2, and the test environment – hardware specification – looks like below.

• Intel Dual-core E6500 2.93GHz
• Samsung 2GB Memory
• WD SATA2 HDD 500GB (7,200 RPM)

The test is done with 100,000 key-value pairs in a single node. Each key and value sizes are 8 bytes. The following is the result of the test in reading and writing comparing to other noSQL solutions like membase and Cassandra.

• membase: writes data for about 28 secs, reads for about 12 secs in average
• cassandra: writes data for about 30 secs, reads for about 72 secs in average
• cloudbean data service: writes data for about 26 secs, reads for 2 secs in average

The optimization in this project means to minimize the data writing to disk. We have developed the prototype version 1.2, which is not stable yet though, the next version 2.0 would be more stable, satisfying ACID properties. Cloudbean is designed to offer a special purposed data model so that we could be prepping for a new kind of cloud service. Long way to go, but we have a vision for delivery.

Pay-to-Play

I think the pay-to-play provision is described well enough in Wikipedia, that says,

Pay to Play is a provision in a corporation’s charter documents (usually inserted as part of a preferred stock financing) that requires stockholders to participate in subsequent stock offerings in order to benefit from certain antidilution protections. If the stockholder does not purchase his or her pro rata share in the subsequent offering, then the stockholder loses the benefit(s) of the antidilution provisions.

As we see, with the provision, the investor may have the right to plugged in the subsequant deal with the prescribed portion. It’s important especially in down round, for the investor who has the shares of Series A Preferred can get more preferred stock in lower price.

If the provision is exerted, the securities would be converted automatically to a series of preferred stock. On the other hand, when it fails they will be converted to a common stock resulting in the loss of all preferential rights – antidilution protection, liquidation preference, Board seat and so on.

This is the second round to cover up the terms in term sheet. The main subject is about liquidation preference, which is concerned with the division of the value when liquidity event – the sale of the company or the majority of the assets – occurs. Notice that liquidation preference is not about control, but utterly about money. It consists of two parts – the actual preference and participation.

Actual Preference

The actual preference is specified with the number which is the multiple of the original investment per share to be returned to investors in preference to the common stock holders. For example, if a series A investor invests $10m with 2x preference, then he will receive $20m in return when the company is sold. Occasionally the number goes higher than 1x, but in most case it is set to 1x.

Participation

Participation is another significant term in liquidation preference. It determines how the money shall be divided and delivered to investors. There are three options in participation.

• Non-participating: It is easy to calculate. In non-participating, the investor gets the pro rata amount of investment. For example, if the sale price is $100m and the investor has 40% of equity with $20m of original price, then the investor will get $40m, or 40% of $100m.
• Participating: Participating increases complexity on the event, yet the concept is simple. The investor may get the original investment price first, and then do calculation with the rest of the money. In the above example, in participating, the investor takes $20m – the original invement price – first and takes 40% of the rest of money, which is $32m or 40% of $80m. So the investor takes $52m in total.
• Participating with cap: Capped participation is a condition statement which indicates that a certain multiple return shall be reached. When the preferred doesn’t reach the cap, the fully participation is applied. See the example again, assuming that the contract is in participating with a 3x cap. As the return ($40m) doesn’t reach the cap ($20m x 3 or $60m), the result would be the same as the participating case. If the purchase price goes up to $200m that it makes better than 3x, the participation doesn’t happen.

Participation makes the deal more complicated because the other fundraising may follow up inevitably. Thus, it’s always better to simplify the liquidation preference especially in early days of business. That is, the entrepreneurs should choose the non-participating option for the future deal.

Term sheet is the primary sentences for the start-ups as they need money from investors. And not to be confused or sneaked by VCs(venture capitalists), the entrepreneurs should keep the terms fully understood. So I share the description of the terms in a series so that the beginners can get the overall terms of term sheet. Today, we’ll see the price and option pool.

Price

Price is the very basic unit of the deal as it is a measure of the valuation of the company. To get into the notion, we need to understand the terms ‘premoney’ and ‘postmoney’ because the investors’ mentioning the valuation would determine the actual value of the company. Premoney, usually called  ’pre’ in short, is the valuation before the investment whereas the postmoney is the valuation including the investment amount.

Let’s see an example. If a VC says, “I will invest $5m at a valuation of $20m,” it usually means the postmoney valuation. As a result, the investor will get 25% of equity – $5m portion of $20m. On the contrary, when the VC clarifies the valuation as premoney, then the VC gets 20% – $5m of total $25m postmoney. So do the math before talking about the price.

Option Pool

There’s one more thing to consider: option pool. Option pool is the equity reserved to compensate the employees, so it is also called as the employee pool. It is important because the entrepreneurs’ share would decrease relative to the increment of the option pool. In the above example of postmoney valuation, suppose that the entrepreneur sets the option pool to 10%. Then what if the VC requests to scale it up to 20%? The VC’s portion doesn’t change though, the founder would hold reduced portion of share, which is 65%, 10% less than the original portion if the request is accepted. Thus, the option pool should be considered if the VC tries to touch this.

There are many other economic terms like liquidation preference, warrants, pay-to-play, vesting and antidliution in term sheet. I will compact the description of the terms into the summary as if I posted here today. Next time we’ll see the term, liquidation preference.

For example, it’s possible that a game company who uses this database model can link game data to other records in online shopping mall database. The main idea has been applied to the patent, and now I participate in the development of the project which name is Cloudbean. The patent involves the content about domain rule and domain access control as well as the linked record pair stuff. In reality, the system may serve the link attributes as well.

SNS is shaking the tract of business. Some subordinate keywords emerged. Social game, social shopping, social ERP and other *social* things around. And new business opportunity arises while those social keywords being entrenched.

Also there’s a chance for the items strengthen the movement. For example, dating site would move to social dating or auction might go with social commerce like Groupon and LivingSocial. Zynga, the social game company in Facebook, is now bigger than most other game companies. The power is immense.

What a tragedy for services drained by SNS. The thing to learn is, no business lasts forever.

Suppose that you heard a news from a friend that new iPad3 design and specs are leaked. At first you may wonder it’s true or not because you know that iPad2 launch day was just a couple of weeks ago. After a while another friend tells you the same story, and then it becomes a fact. You’ll soon enter “iPad3″ into Google search bar. The point is, just 2 or more friends make you believe something.

We trust search result from Google or Wikipedia. Is that trustworthy? Many resources are on the stage but not guaranteed. And we, the irrationals, use the information for doing business. By abusing this trait maliciously, one guy can agitate the herd as the internet connects all over the world.

One good example of this is, so called, social engineering. Although the security system is completely safe technically, human is not perfect. If somebody exploits the vulnerable point of that guy who organizes the system, hacking done.

Ignoring irrational tendency is more risky than accepting the weakness. And I think being irrational is a part of risk management.

Some of them might be differ from yours as they come from my laptop. For example, the value of IE8 involves .NET notations. That’s because I’ve installed .NET platform version 2.0, 3.0, 3.5 and 4.0. Thus, please don’t care about it.

Although there are more browsers, I think major browsers are already dealt.

Header Fields for HTTP Request

[ Dice gives us fun because it shows uncertainty. But dicey. ]

Success in business requires the satisfaction in myriads of views. But few thinks about the uncertainty, which motivates and accelerates the one. If you are not sure that the business works, you cannot affirm the employees to go on the way. And that would stuck in there. Never go further.

However, that kind of conviction is differ from the recklessness. I hope to share my opinion on how to distinguish the actual conviction from the brute courage. Please checkout the points below and reponse me for correction if needed.

• It should be sustainable. If it temporarily survives, it’s going with the temporary feeling. Intuition is quite different with the feeling that intuition is sustainable. Sustainability involves the financial
• It should be programmable. Without the programmability, the belief is just a pipe dream. It is the most difficult to figure out before kicking off the business so it needs the help from experts.
• It should require more opinions. The idea need to be shared so that you could know how other people are thinking about the issue. Maybe more possible options are not weighed just because you thought it alone.
• It should be scalable. The need in market can change. The scalability makes more flexible when the market changes. For example, people designing TV business like Google-TV should consider the usability of any other devices as well in case the future technology evolves and expands into other platforms.

Well.. lots of more things to consider. But here I suggested is the core values for business I think. And they are what I consider whenever thinking about new business. You’d rather trust your business with those equipped.

Most database management system enacted on RDBMS(Relational Database Management System) base. The keyword is “Relational.” The way how to make relations mostly determines the whole performance.

There are 3 types of relation – 1:1, 1:n and n:m. Let’s take a look for each.

One-to-One(1:1) relation
Although it is rarely used as all 1:1 relations can be expressed as one composite dataset, understanding the concept would help to see the connections more clear. A student and his student ID match is an example. One student has one ID and one ID is possessed by one student.

One-to-Many(1:n) relation
It is the most common relation that most hierarchical structure can be represented with it. For example, suppose that 16 full-time employees are working in a company. Then the company has 16 employees, and each employee belong to one company.

Many-to-Many(n:m) relation
This relation is the most complicated structure among relations so it requires the performance overhead. It traverses N*M times to search for data while One-to-Many relation does it N times. One of good examples is the relation between class and student. Students take many classes and each class has many students.

The key is that, avoid Many-to-Many relation to maximize performance. If it is inevitable, count the number of data records and control it with discussion. The performance is not to be ignored in web service.

In terms of project management, issue is the base unit of the project. Somebody may find a bug or may want to cast an idea. It is an issue, which could act as a fertilizer. People involved would try to solve any problems or to make it real. Finally it nurtures the process and gets rid of confusion.

What if there is a project which is going without that kind of tool? Well.. it would go fine except that it takes much more time – that is, by wasting your time. For example, the manager and team members get many time-breaking meetings when something has been changed. Working not understood puts a collide in. I cannot exaggerate that this would obfuscate the matter.

The tools like Trac, Bugzilla, Redmine are great. Sharing should be promoted that every members could get the issues and make the project healthy.

Sometimes go-getters miss that they should pertain their business. Without considering the point, the business comes to be easily in panic. People will surge in at a time (at first) and out soon after.

Then how could we take it into account?

Simulate it. Prototyping might help. Or offering to normal people would give you some responses about the business. There is bunch of ways to figure that out.

Usually good idea makes “ta-da” moment. But without sustainability, it could not aggregate the fortune. That is, it is not profitable at all.

Popularity is a different kind of matter. Popular people don’t need to be skillful. Yet many followers may tell us the reason why they are popular, those bids might not be correct. There are lots of guys who match the characteristics but are not popular.

Why, then, are they popular? It is a conundrum for marketers. They usually ask, ”We furnish a great service with no charge but people don’t use our service. What’s wrong with that?” Again, popularity is totally differ from skill.

Then how could we make something popular? Well.. there’s no magic formula but there are some prerequisite. The quality of what you serve, trust and attractiveness. Remember that two of those are emotional. Even the bad quality could give a negative effect by making people furious. Human things are one of the most difficult things to control as emotion is amorphous. Getting more skill is good. But that’s not crucial for popularity.