2. OVERVIEW
CLOUD COMPUTING : means storing and accessing data and programs over
internet instead of your computer’s hard drive.
DEPLOYMENT MODELS :
. Public Cloud
. Private Cloud
. Hybrid Cloud
. Community Cloud
3. SERVICE MODELS :
. Infrastructure as a Service (IaaS)
Ex-Amazon EC2, RackSpace ,etc.
. Platform as a Service (PaaS)-
Ex- Google App Engine and Microsoft Azure,etc.
. Software as a Service (SaaS)-
Ex- Gmail , Dropbox, etc.
4. FACTORS AFFECTING CLOUD COMPUTING PERFORMANCE
1. Security – The impact of security on cloud performance may seem lightly strange , but the
impact of security on network infrastructure has been proven . For ex- DDoS attacks have wide
impact on network performance and if happen ,it will greatly reduce network performance and also
be effective on response time too.
2. Service Level Agreements – The better, more optimal and more timely the agreed requests ,
the higher performance will be.
3. Recovery - Cloud performance may be affected due to the time required for the data retrieval
and amount of data which are recoverable.
4. Storage Capacity – Physical memory can also be effective on the performance.
5. Buffer Capacity - If the buffer capacity is low many requests will be rejected and therefore
performance will be low.
6. Disk capacity – can also have positive or negative impact on performance in cloud.
7. Network Bandwidth – If the bandwidth is too low to provide the service to clients, performance
will be low and vice-versa.
5. 8. Fault Tolerance – If the data center is in deficient and is able to provide
minimum services , this can increase the performance.
9. Availability – With easy access to cloud services and the services are always
available , performance will increase.
10. Number of Users –Increase in the number of users will reduce the
performance of services.
11. Location – If the data center is too distant from the user’s location this may
reduce the performance.
12. Workload – In a cloud environment ,the larger and less predictable workload
also leads to greater variability in service delivery.
13. Latency – Latency greatly influence how usable and enjoyable devices and
communications are.
FACTORS AFFECTING CLOUD COMPUTING PERFORMANCE
6. PERFORMANCE EVALUATION CRITERIA
There are number of criteria for evaluation of all factors affecting the
cloud computing performance . Some of the criteria are such as :
Network capacity per seconds
The number of I/O commands per seconds
Average Response Time per unit time
Percentage of CPU utilization
Throughput
Workload
Average waiting time per unit time
The average time of processing
The number of requests executed per unit time