Strategic Management Documentation

Weaknesses.

• As Amazon adds new categories to its business, it risks damaging its brand. Amazon is the number one retailer for books. Toy-R-Us is the number one retailers for toys and games. Imagine if Toys-R-Us began to sell books. This would confuse its consumers and endanger its brands. In the same way, many of the new categories, for example automotive, may prove to be too confusing for customers.
• The company may at some point need to reconsider its strategy of offering free shipping to customers. It is a fair strategy since one could visit a more local retailer, and pay no costs. However, it is rumoured that shipping costs could be up to $500m, and such a high figure would undoubtedly erode profits.

Opportunities.

• The company is now increasingly cashing in on its credentials as an online retail pioneer by selling its expertise to major store groups. For example, British retailer Marks and Spencer announced a joint venture with Amazon to sell its products and service online. Other recent collaborations have been with Target, Toys-R-Us and the NBA. Amazon's new Luxembourg-based division aims to provide tailored services to retailers as a technology service provider in Europe.
• There are also opportunities for Amazon to build collaborations with the public sector. For example the company announced a deal with the British Library, London, in 2004. The benefit is that customers c an search for rare or antique books. The library's catalogue of published works is now on the Amazon website, meaning it has details of more than 2.5m books on the site.
• In 2004 Amazon moved into the Chinese market, by buying china's biggest online retailer, Joyo.com . The deal was reported to be worth around $75m (£40m). Joyo.com has many similarities to its new owner, in that it retails books, movies, toys, and music at discounted prices.

Threats

• All successful Internet businesses attract competition. Since Amazon sells the same or similar products as high street retailers and other online businesses, it may become more and more difficult to differentiate the brand from its competitors. Amazon does have it s brand. It also has a huge range of products. Otherwise, price competition could damage the business.
• International competitors may also intrude upon Amazon as it expands. Those domestic (US-based) rivals unable to compete with Amazon in the US, may entrench overseas and compete with them on foreign fronts. Joint ventures, strategic alliances and mergers could see Amazon losing its top position in some markets.
• The products that Amazon sells tend to be bought as gifts, especially at Christmas. This means that there is an element of seasonality to the business. However, by trading in overseas markets in different cultures such seasonality may not be enduring.

Weaknesses.

• The organizations works tremendously hard to overcome fraud. However, the eBay model does leave itself open to a number of fraudulent activities. Often the company deals with such activities very quickly. Fraud includes counterfeit goods being marketed to unsuspecting (and suspecting!) eBayers. Other forms of theft could include the redistribution of stolen goods. It should be pointed out that fraud and theft are problems with individuals, not eBay. The weakness is that unscrupulous individuals can exploit the C2C business model.
• As with many technology companies, systems breakdowns could disturb the trading activities of eBay. In the past both eBay and its payment brand Paypal have encountered shutdowns and outages. As technology improves such a weakness is less and less of an issue.

Opportunities.

• Acquisitions provide new business strategy opportunities. eBay has agreed to buy online telephone company Skype Technologies in a deal reported to be worth $2.6 billion. Skype's software lets PC users talk to each other for free and make cut-price calls to mobiles and landlines. eBay has been buying up firms - including payment system PayPal - in an effort to increase the number of services it offers to consumers and keep its profits growing.
• New and emerging markets provide opportunities (Market Development). Countries include China and India. There, consumers are becoming richer and have more leisure time than previous generations. Aspirating consumers are a growing segment in many developing nations.
• There are also still opportunities in current markets (Market Penetration). Western Europe and the USA still have many potential consumers that have yet to discover the benefits of online auctions. Remember products have life cycles that eventually come to an end, and such products are ideal for selling and buying on eBay.

Threats.

• As with many of the global Internet brands, success attracts competition. International competitors competing in their domestic markets may have the cultural experience that could give them a competitive advantage over eBay. In fact eBay has found that it has met with other USA-based Internet companies when trading overseas. For example, Yahoo! dominates the Japanese market.
• Attack by illegal practices is a threat. As with weaknesses above, the brand is attacked by unscrupulous individuals. For example e-mails are sent to unsuspecting eBayers pretending to come from eBay. Logos and the design of the pages look authentic. However they are designed so that you input private information that the thieves can use to take passwords and identifications. -so beware!
• Some costs cannot be controlled by eBay. For example delivery charges and credit card charges. If fuel prices were to rise, the cost is passed on to the consumer in terms of delivery and postal fees. This could make the overall cost of an auctioned item too expensive. Similarly, if a credit card company such as Visa or Mastercard imposed a charge for online transaction, the total cost of the same items would increase with similar consequences.

Founded in September 1995, eBay (Nasdaq: EBAY) is The World's Online Marketplace® for the sale of goods and services by a diverse community of individuals and small businesses. Today, the eBay community includes more than a hundred million registered members from around the world. People spend more time on eBay than any other online site, making it the most popular shopping destination on the Internet. More . . .

Weaknesses.

• Differentiation is difficult for Yahoo!. Almost all of its packaged services are available from other sources.
1. (i)Search facilities are available on MSN and Google.
2. (ii)Free E-mail accounts are available from Hotmail (MSN) or G-Mail (Google), and many, many others.
3. (iii)New is available from CNN or the BBC.
4. (iv)Shopping is available everywhere on the Internet. Google has Froogle.

• Online advertising is a new income stream for organizations such as MSN, Yahoo! and Goggle. Yes, today they are very, very profitable. However, as technology develops and new unforeseen advertising media emerge, the future is uncertain for these income streams. This is a weakness for Yahoo! and its competitors.
• Another income stream that has been key to Yahoo! is derived from its partnerships with telecommunication providers. For example, you buy an Internet connection package from your local telephone company, and it includes a fee-based Yahoo! package including e-mail accounts, user support and other added value services. If ever this channel is changed or removed, the income stream would be affected.

Opportunities

• The international market is a huge opportunity for Yahoo!. Yahoo!, Microsoft and Google are busy carving niches and taking over businesses in are around the Greater China Region. China has over 1,200,000,000 citizens. Other economies, such as India, also offer tremendous growth potential.
• The Development of the Yahoo! Directory has potential for new business and income streams. Two thirds of organizations in Ohmae's Triad (Europe, Japan and the USA) are Small Medium Enterprises (SME'). SME's are potential directory advertisers.
• Mobile technologies offer another opportunity for Yahoo!. Today we access the Internet using personal computers. Tomorrow phones, televisions, personal organisers, music players and computers will merge and morph. The mobile devices of the future will need services and solutions. Yahoo! would be well placed to provide many of them.

Threats.

• The biggest threat for all web-based organization is competition. Huge profits attract investors, innovators and entrepreneurs. Dotcom fever has not gone away, it is now more focused on profit delivery. All of Yahoo!'s key services have competitors such as AOL, Google and many others.
• International, culture specific competitors could affect Yahoo! in the future, unless strategic alliances are forged. China has developed its own search engines, as has India. Why should the World use USA based companies such as Yahoo!? There needs to be a series of substantial competitive advantages to see the business remain as an international brand. Look at what has been learned from the global car industry, or electronics industry.

When Yahoo!! was founded in 1994 by Stanford Ph.D. students, David Filo and Jerry Yang, it began as their hobby and has evolved into a global brand that has changed the way people communicate with each other, find and access information, and make purchases. More.

Description:
a. multiprogramming for 4 programs in memory
b. conceptual model for 4 independent process, sequential
c. only 1 program is active in 1 time = pseudoparalel

Hierarchy Process
Calling the process by another process called parallel. Operating system provides what is needed by the process. Generally, the process created and removed during the operation lasted.

1. Create & Destroy Process
Operating system that supports the concept of the process, should provide a way to (create) the process and eliminate (Destroy) process.
2. Fork System Call
Mechanism to create (create) a process that is identical with the process that call.
Example:
Parent -> children
->children -> children
->children
In UNIX, parent and child process running in parallel.
In DOS, parent and child process running alternately (sequential). For example: MSDOS as a parent and program applications as a child.

Process scheduler for the execution process

Status of the 3 / the state of the process:
1. Running / work, really use the CPU at that time (instructions are in the process of executing it).
2. Blocked / stopped, can not walk up to an external activities involved (the accident waiting to complete its work)
Can be a process of waiting: the completion of operating the device I / O; Availability of memory; arrival message answers
3. Ready / ready, the process is done, but ready to wait another turn with a process that is being done (can walk, stop temporarily to allow other process is done)

Transitional Status

1. The process in the block to serve as the input of resources that are not yet available / ask the service I / O wait until incidents occur.
2. Scheduling take the other.
3. Scheduling take this process (new).
4. Input has been available.

Implementation Process:

• To model the process, the operating system using a table / array called the table with 1 per-entry process.
• Each entry contains about: the status process, the program counter, stack pointer, memory allocation, the status of the files, information schedulling / scheduling information, etc. from the status of work to ready status.
• Interupsi: Work on the processor a process stopped by pensaklaran context.
• Pensaklaran context: changes in the activities of the processor to process that occurs between the system / application process
• Context: the processor to the case, comes from the operating system, language system and system utilities.
• Block control the process: a memory to record the state of the process, which is divided into areas where each region to record different information.

2 interruptions in the processor:

1. Interruptions directly

Derived from outside the processor (peripheral / tool send a signal to the processor to request services)

2. Ask interruptions / Polling

Derived from the processor (the processor in turns to check whether there are peripherals that require services or not)

• Interupsi-in can enable and disable depending on the level.
• The interruptions can come from:
• Program, the program has been designed in a certain part will happen pensaklaran context, that causes interruptions, for example, when the use of tools / processor alternates.
• Processors, the processor can generate its own interruption, the normal process arithmetic and logic. If melampoi size patch registers in the processor, then there will be a mistake menginterupsi own work and submit a control processor on the operating system. For example, the division of the number zero.
• Unit of control, the task to implement the interruption is located on the control unit, so that the control unit can generate interruptions. For example, confusion instructions
• Key time / clock, using the interruption periodic. For example, the program anahammad the infinite, diinterupsi on the lapse of time every 60 seconds.
• Peripheral I / O, I / O will work if you let the processor with the processor interruptions and also when the work is completed or when the error occurred parity.
• Memory, because the error occurred, for example, when the processor wants to reach the address of the memory is located outside the expanse of memory address.
• other resources, for instance, raised by the service computer system that understands how interruptions.

• Interupsi vector: Contains procedures address service interruptions
• Revenue interruptions and interruptions necessary: sometimes rejected by the interruption processor or interruptions that come not only one that required priority.

Follow-up interruptions:
1. Organized interruptions / Interrupt handlers
if the interruption occurs, the control processor submitted to the interruptions in the system’s operation, it’s interruption is conducting interruptions.
a. Instructions are processed by the processor left to complete the program.
b. Organized interruptions record all the information to process control block in the process.
c. Organized interruptions to identify the type and origin of interruptions.
d. Organized interruptions to take action in accordance with the definition interruptions.
e. Organized interruptions prepare everything for the resumption of the process diinterupsi.
2. Organized wrong / error handlers
namely interruptions because of confusion on the part of the process and the processing of the operating system up activities resulting’s mistake is misleading.
a. Recovery, the computer has been equipped with a password error discovery and recovery, for example, have been equipped with a password so that when Hamming find the password will correct the mistake error, the process is restored to original form before the error occurred.
b. Repetition, set the process in order to generate the interruption mistakenly re-done, if the error can be solved then the process will take place as usual, if you do not feel the interruptions will tread the follow-up out of the process.
c. Exit from the process,’s blunder prepare mistaken view news from the monitor, the processor out of the process, this is the last action can not be helped if the process is wrong.

Follow-up interruptions, according to Peterson & Silberschatz:

Description:
1. Completed
The program implemented by the processor has finished so that the transfer of the control process to a new job / new command because the process is done by the processor has been completed.
2. Misrepresentation
If the error is displayed, and the control processor is the next in command.
3. Demand is not the tool of I / O
After the interruption was completed, the control processor returned to the original process, for example, periodic interruptions.
4. Demand from the tool I / O
After the interruption was completed, the control processor returned to the previous process, but sometimes the processor intervene in the working tools of I / O control of the process so that the original, does not take place immediately / waiting.
5. Completed from the instrument I / O
After the interruption was finished and finished signs note, the control processor returned to the original. Usually tool for I / O is not diikut campuri by the processor.

Catt:
1 & 2 does not restore the processor to process the terinterupsi, while
3,4,5 restore the processor to process the terinterupsi.

Step-by-step operating system at the time of the interruption:
1. hardware enter the program counter, dl.l.
to enter the stack in the census program
2. Hardware load (load) of the program counter of the new vector interrupsi
3. Procedure language assembled to save the contents of the register
4. Procedure language assembled set a new stack
5. Procedure C to mark the service is ready (ready)
6. Scheduler / scheduling process of determining which roads will be next
7. Procedure C back to the mode of language assembled
8. Procedure language assembled begin the process of being implemented.

Inter-process communication
(Inter Process Communinication / IPC):

• Some of the process usually communicate with other processes.
• For example in the shell pipe line: the output of the process must first be given to the process to two and so on.
• In some operating systems, processes that often work together sharing (shared) storage media, a process which can read and write on the shared storage (main memory or files)

The problem - a problem in the IPC:

Race Condition:
A condition where two or more processes to access the shared memory / data at the same time, and the end result is not in accordance with the desired
Example COULD’VE Condition:

• Print spooler
• Example: a collection of data that will be in print.
• Spooler directory
• process A -> check of the input slot is empty (7) to print data and a stop
• Interupsi … … …
• process B -> the data will be put in print in the empty slot (7) and stop (the slot is empty the next 7 1 =
• : the processor to process other
• process A -> resumed  data will be put in print in the slot (7), so to overwrite the data process B that is placed in the slot (7)
• The process B will not be implemented, and will not be detected in error.

To avoid race conditions, it must be regulated so that the 2-critical process that has the same section does not enter the critical section at the same time.

Critical Section / critical section:
Part of the program to access a shared memory, which can cause race conditions.
4 condition to prevent race conditions:
a. 2 does not enter the critical process that simultaneously sectionnya / simultan
b. No assumptions are made regarding the speed and number of CPUs
c. No process that runs outside of its critical section that can block any other process
d. No process is waiting forever for the entry into its critical section.

Mutual Exclusion (MuTex) With Busy Waiting:
If a process is accessing the shared memory in critical sectionnya, no one can enter percent of the critical section (mutual Exclusion) and cause problems.

The types of mutual Exclusion:
1. This Interrupt / off interruptions
By the way shut incoming interruption during the process is in its critical section. This is sometimes quite useful to the kernel, but not for the user. And how starters are not too good for the CPU, the number of which more than one, where only about Interrupt disable the CPU are running the process and do not affect other CPU
2. Lock variables
Each process will be access to the critical section will need to check lock variable. 0 If the process can enter its critical section 1, and if the process must wait until the lock variable = 0. The disadvantage is 2 process can still enter the critical section is at the same time. During the one-check process to lock variable = 0, when will set 1 no interruptions to the process of implementing others who also want to enter the critical sectionnya, there will be race conditions.
3. Strict alternation
By observing variable turn to determine who will enter a critical section is not a good idea if the process slower than the other.
For example:
While (true)
(
While (turn! = 0) / * wait * /;
Critical_section ();
Turn = 1;
Noncritical_section ();
)
while (true)
(
While (turn! = 1) / * wait * /;
Critical_section ();
Turn = 0;
noncritical_section ();
)
4. Peterson’s Solution
The process will not be fulfilled until he is ready, if interested in [other] = TRUE, then the process will wait until FALSE.
The disadvantage: if the call enter_region it is almost the same time, which in turn is stored data that is written last.
For example:
# Include “prototype.h”
# Define FALSE 0
# Define TRUE 1
# Define N 2 / * number of processes * /

int turn;
int interested [N]; / * initial value is set = 0 (false) * /
void enter_region (int process) / * process = 1 or 0 * /

(
int other; / * number of other processes * /
other = 1 - process; / * other processes * /
interested [process] = TRUE; / * indicates interested * /
turn = process; / * set of flags * /
while (turn == process & interested [other] == TRUE)
)

void leave_region (int process) / * process is finished * /
(
interested [process] = FALSE; / * leave critical region * /
)
5. Test and Instruction Set Lock / TSL Instruction
With the help of hardware, determine who has the right to enter critical_region (section)
Example:
Enter_region :
Tsl reg,flag | copy flag ke reg dan set flag = 1
Cmp reg,#0 | apakah flag = 0
Jnz enter_region |jika <> 0 loop lagi
Ret |return ke caller, masuk critical region

Leave_region :
Mov flag, #0 |simpan 0 ke flag
Ret |return ke caller
This process must call at the right time.
The main weakness with everyone waiting is more and more CPU time and priority inversion problem.
6. Sleep and Wake Up
Mechanism: the process will be in the block / sleep (sleep) when critical_section can not enter it and will be developed (its people up) / readily when resources needed are available.
SLEEP: the system call to make the process of calling in blocks (blocked)
WAKE UP: call system that make the process ready to call menjasi
Example:
Procedure-Consumer Problem (bounded buffer)
Some share the process with the size of the buffer remain
If the buffer is full sleep Producer
If the buffer empty consumer sleep
If the buffer starts to empty its people up Producer
If the buffer filled up consumer its people
There is still a possibility the race Condition
7. Semaphore (Dijkstra, 1965)
To check, change and sleep 1 instructions
Change and its people up inseparability
Instruction is very useful for synchronization.
Can be implemented to solve Producer-consumer problem.
Mechanism its use:
- Integer variables to calculate the number of its people who saved up / delayed
- 0 valued when its people are not kept up, there is a positive value when its people up pending

Two kinds of operations against the semaphore:
DOWN(S) :
If S >= 0 then
S := S-1;
Else sleep (S)
End;

UP(S) :
If S <= 0 then wakeup(S) End;

Production is down and UP operations are Atomic (Atomic Action).
8. Event counters (Reed and Kanodia, 1979)
Three operations on the event counter (E):
1. Read (E): the return of current value of E
2. Advance (E): Atomically increment E by 1
3. Wait until E has a value of more or v
9. Monitors
- Higher levels Synchronization primitive.
- Collection procedures, variables and data structures that dipaket into one module or package.
- The process can call the procedure in the monitor, but can not directly access the data structure of the internal monitor.
10. Message Passing
Use 2 primitive:
1. send (destination, & message)
2. receive (source, & message)
Some issues on the message passing system: lost message; acknowledgement; domains; authentication; performance

Classic IPC problems:

• The Dining Philosopher Problem

- 5 philosophers who work only eat and think
- Spaghetti available five plates and five chopsticks
- Needed to eat fruit bua chopsticks
- Its problem-how to write the program so that every philosopher can think and eat each other without having to wait?

• The Readers and Writers Problem

- Model access to the database
- Many of the process to compete for reading and writing. For example: airline reservation.
- Some processes can be read at the same time
- If a process is writing, the process can not be any other database access
- The process to have a higher priority than the process of writing

There are 3 models in the process server:

1. to create the thread can do paralelisme combined with the execution sekuensial and blocking system calls
2. treads a single server, using the blocking system calls, but system performance is not good
3. finite-state machine, with good performance parallelisme do, but using nonblocking calls, so difficult in the program