Service-orieneted Architectures

Phil Windley writes about SOA and complexity:

Service oriented architectures (SOAs) are about reuse. The goal of a service-oriented architecture is to build applications using modules that (1) look like network services, (2) are potentially very far away and (3) perhaps owned by someone else. There are some significant benefits to be had including reduced hardware expenses, fewer systems to operate and maintain, and better software reuse. All of these benefits come at the expense of significantly increased complexity.

There are basically three problems:

No one team understands or controls all the moving parts. Problems have much wider impact. As the second schematic shows, there is a big ripple effect for service failures, increased latency, security lapses, and so on.
Change management is more complex. Parts need to be added, upgraded, fixed, and replaced on the fly with no external impact. In an SOA, expected level of service can change after its put into production. For example, we may put a module into service and then increase its expected service level when it is incorporated into a new, mission critical application.
Separation of concerns is more difficult. Stake-holders (operations, engineering, security, lines of business) need to be able to do their jobs without having constant interaction. Traditionally, deployment is the time when all stake-holders come together. Moving to an SOA can’t cause the entire business to be reorganized. For example, when a privacy policy is changed, does everyone need to get together or can just the privacy officer and operations make the change without involving development and the lines of business?

Patrick Logan discusses these points further and concludes: “To reiterate I believe the movement toward an SOA will be preceeded by a movement to realign IT for the enterprise architecture and go hand in hand with vendor and product consolidation, and less custom development. Without these steps, then yes, the future looks unmanageably complex. *With* these steps the future is still complex because the changes will be gradual and IT will continue to deal with the as-is and the to-be concurrently. But at least there is hope if the SOA products mature and rational principles are in place for their adoption.”

China’s Cheap PC Plans

[via Bala] Asia Times writes:

Culturecom Holdings Ltd says its new V-Dragon CPU, which retails for only US$15-$30, will reduce the price of PCs and appliances by anywhere from 50-70 percent, mostly by eliminating costly intellectual-property (IP) fees charged by “Wintel” – Microsoft and Intel – for their operating systems and CPUs.

Co-developed by IBM and based on the Midori Linux operating system, the new V-Dragon architecture aims specifically for the Greater China market with an embedded dynamic Chinese character-generating engine, allowing direct use of 32,000 Chinese characters without additional font sets or Chinese language peripherals.

“The V-Dragon is not only the first Chinese CPU, its also the first Linux-based CPU,” Culturecom senior vice president Benjamin Lau told Asia Times Online. “Midori Linux is a flexible OS [operating system], and it’s the only Linux OS whose design team was led by [Linux creator] Linus Torvalds himself,” Lau added. Culturecom acquired rights to Midori Linux from the US-base company Transmeta.

Lau said that Culturecom forecasts shipments this year of between 1.5 million and 2 million units. Most are for intelligent appliances (IA) such as smart digital video disc (DVD) players, or for special-purpose terminals such as the tax terminals Chinese equipment vendor Datang is building, and for which it has ordered 300,000 V-Dragon CPUs.

Critics have suggested that the Chinese CPU’s speed is prohibitively slow, but Lau disagrees. “The V-Dragon CPU offers speeds anywhere from 400 megahertz to 1.4 gigahertz,” Lau told Asia Times Online. “For Datang’s tax terminals, for example, they only need 400MHz processors. Some of our customers want faster CPUs, and we can meet that need.”

In a market where PC penetration remains extremely low – 3.3 million PCs were sold in 2003 in a country with a population of 1.3 billion – Culturecom is hoping that its low-cost CPUs will help to bridge the gaping “digital divide”. Simple desktop computers powered by V-Dragon CPUs and sufficient to browse the Internet would cost as little as $200.

“We can serve the mass population of China,” said Lau. “The vast rural population desperately needs access to affordable IT.”

Rather than trying to make desktops, they should looks at making thin clients based around the chip. What’s needed is a redefinition of the architecture given the presence of networks.