During the New Year of 2012, I traveled to China. During
this short 10-day trip, I stopped by 5 cities;
Beijing, Shanghai,
Nanjing,
Guanzhou and Shenzheng. I was indeed very exited to see a lot of improvements
in many areas, such as quality of service and living standards. When I landed
in Pudong airport (Shanghai), the Chinese
Customs and Board Control was so efficient and friendly that I immediately felt
a difference from my last trip to China a few years ago. From
Shanghai to Nanjing, I sat on the bullet train (Gaotie) that took a little more
than an hour and traveled about three
hundred kilometers distance. What is amazing to me is that Chinese railway
system is automated from ticketing to check-in. The long queue to buy tickets
and crowded manual check-in is just old memories. As an IT professional, I can
surely bet that those improvements are closely resulted from advancement of IT
in Chinese industries.
Talking about the Chinese railway system, it is probably the
largest one in the world (India
is the second). Right after the New Year, the Chinese Railway Authority announced
the change of ticket regulations, namely identity documents are mandatory when
purchasing tickets. This requires the implementation of a few major business
rules, such as one account can only be associated with one identity card, and
one identity card can only buy one ticket on the same train of the same day, etc.
The other change is the improvement of capability of purchasing tickets via
online system. According to the Chinese media, the amount of online tickets
sold reached 23.6% of total tickets sold, which is a quite achievement.
However, I was quite disappointed about two deficiencies of
the Chinese railway online purchasing system. One is that you can only purchase
tickets during 6:00AM to 11:00PM. The other is there were many incidents that
people didn’t get tickets even after their credit cards were charged. Many
Chinese people may take these deficiencies as granted and reasonable. The
amount of trouble caused to people if their credit cards are charged without
the tickets, would scare me. These things would damage any company’s business
in the U.S.
In fact, 24 by 7 and 3 to 4 nine digits (99.9% to 99.99%) availability have
already become norm for mission critical business with US companies. As a
result, we can see that the gaps of IT maturity exit between Chinese industries
and US counterparts.
Although I am not completely sure why the window is imposed
for buying the tickets from to 6:00AM to 11:00PM, it is most probably due to
the limited backend batch processing and data replication/synchronization
capabilities. People in China
may argue that the 11:00PM to 6:00AM unavailability may not be a big deal,
since it is night time and there is only one time zone across whole China. However,
how about the people from other countries in different time zones such as North
America or Europe to buy the tickets online? I
remember that one of my previous projects was to provide improvements for a
major US
hotel online reservation system. This project was initiated as a result of the
incident that the system was down for only 2 hours, which cost the company a few million dollars.
Comparing one time of 2 hours down time with 7 hours down time daily happening
to the Chinese railway online purchasing system, I am wondering how much money has
been lost and will be lost due to the 7 hours unavailability daily.
In addition, it
would be a joke in the US
if a system would charge a credit card without delivering the ticket. The Chinese railway online purchasing system attributed it to the 30 minutes
allocated to each transaction of purchases, as per the reports from the TV news
and newspapers. The 30 minutes must be the so-called session for each Web
access. The expiration of a session is not new. Many platforms and Web environments
are able to detect the expiration. Together with a good design, the session
expiration can be easily fixed.
The success of
developing any IT systems must follow well-established methods. The system
development life-cycle (SDLC) should not be very new to Chinese, thinking about
how fast technology has been evolved in China. However, I would like to
share a few points relating to the improvement of the Chinese railway online purchasing
system.
Pay
Attention to Nonfunctional Requirements.
Before starting
any IT projects, the project team must collect and well understand the
requirements. Requirements can be distinguished into 2 categories. One is functional,
the other is nonfunctional. Functional requirements specify, in general, the
system behaviors or functions terms of business logics. Nonfunctional
requirements state that the attributes and quality of the system, such as
security, performance, operability, etc. Both are equally important to the
success of the project. However, many times during the initial stage of a
project, people focus more on the functional requirements, while the importance
of nonfunctional requirements are not fully recognized. This is probably
because the functionality of a system is more tangible and accessible than the
attributes of the system.
In fact, nonfunctional
requirements must be taken into account from the very beginning when designing
a system. Some nonfunctional requirements should be specified quantifiably, for
example, the response time or availability of the system. The cost of
retrofitting these requirements onto an existing design can be easily exceeded
the initial development cost. To avoid such situations, it is imperative that
significant nonfunctional requirements be identified and accommodated in the
earliest stages of architecture. Without defining and meeting the
nonfunctional requirements, the project will deem to fail for delivering
satisfied business benefits. Furthermore, many nonfunctional requirements are architecture issues, not a component design issue (high availability is one of them). This is why you must consider them as part of your architecture.
Architecture
and Design
The architecture
and design of an IT system are big topics that cannot be encompassed within
this short discussion. From very high level, the architecture has to be determined
based on the business values that the system can deliver. Architecture can be
designed in terms of layers, for example, network, infrastructure, information
and application architectures. A more advanced choice of architectures is Service
Oriented Architecture (SOA). The primary objectives of utilizing SOA are to
automate a business process and make it agile. In addition, a universal
infrastructure layer such as Enterprise Service Bus (ESB) can bring many
advantages. Furthermore, the data center architecture of failover is very
essential for the disaster recovery of a critical system such as the Chinese
railway online purchasing system.
Down to the
level of design, numerous design choices and decisions must be made to maximize
the efficiency and effectiveness of the system. Design principals must be kept
in mind all the time. Just to name a few principals here such as; loose
coupling, encapsulation, interoperability, inherent reusability and extensibility,
universal accessibility, stable interface and stay with open standards. The
design choice and decision can make a lot of difference for the system behavior
and performance.
Back to the 30
minutes session expiration issue that the Chinese railway online purchasing
system is facing (as described
above), I believe that a right design, together with the choice of using
capable products, should be able to fix the problem or mitigate the risks. In terms of design, the
well-know ACID principal and XA protocol for distributed transactions should be followed. ACID stands for atomicity,
consistency, isolation, durability, which is a set of properties that guarantee
database transactions are processed reliably. ACID is not new, it has been with
computer sciences for more than 30 years. Hence, it must be known to Chinese
railway online project team. ACID is rather a piece of cake if a transaction is
implemented within one database. However, it becomes very challenging if the
transaction crosses over different systems. In the latter case, it is the case
of so-called global transaction. The underlying mechnisms of the global
transaction is similar to the regular transaction, either it is successful
(committed) if all participants in the global transaction turn on the green
light or failed (roll-back) if any one raises a red flag. In the global
transaction scenario, there must be a component in charge of collecting and
sending messages to all participants as well as making go or no-go decision.
This component is called global transaction coordinator. Major software vendors
have implemented the global transaction coordination capability, such as IBM
product family.
As a
conclusion, on one side I am very pleased to see many IT advances in China. On the
other side, there are still many areas that must be improved further. In
addition, Chinese people need to raise their standard of expectation instead of
taking mediocre reality as granted. The high expectation will result in
business needs and more innovations.
