Design Issues
Design Issues
Several design issues are:
• Openness.
• Transparency.
• Flexibility.
• Reliability.
• Performance.
• Scalability.
Openness
• Offering services according to standard rules that describe the syntax and semantics of these services.
• Easy interact with other systems.
• Advantages of being opened are that open systems are interoperable and portable.
Interoperability means that, opens systems can work together. Portability means that, ability to transform an application from one platform (software or hardware) to another platform.
Transparency
Transparency means that the whole network of distributed system looks as a single computer system to its users.
Various types of transparency are listed here:
|
Transparency |
Description |
|
Access |
Hide differences in data representation and how a resource is accessed |
|
Location |
Hide where a resource is located |
|
Migration |
Hide that a resource may move to another location |
|
Relocation |
Hide that a resource may be moved to another location while in use |
|
Replication |
Hide that several copies of a resource exist |
|
Concurrency |
Hide that a resource may be shared by several competitive users |
|
Failure |
Hide the failure and recovery of a resource |
|
Persistence |
Hide whether a (software) resource is in memory or on disk |
Flexibility
Flexibility means the system should be flexible to the changes in the system.
Reliability
Reliability occurs in the distributed systems as when one system goes down; its job is done by other system. As the chance of all the system in a network going down is less, thus distributed systems are more reliable.
Performance
Building out the system which provides flexibility, transparency and reliability would not help if performance is low. Performance is a key issue. An application running on distributed system should not be slow on comparing to uni-processor system.
Scalability
A scalable system is that system which can handle additional number of users or resources without having to lose some of the performance factor.
Posted in Information Technology, Distributed Systems | 