DISTRIBUTED SYSTEM

                                                                                                 DISTRIBUTED SYSTEM NOTES ,IOE,BCA

DISTRIBUTED OBJECTS 

Distributed objects are reusable software components that can be distributed and accessed by the user across the network. These objects can be assembled into distributed applications. 

Distributed objects are objects that reside in different locations within a distributed system but can communicate and interact as if they were in the same address space. This approach is common in object-oriented distributed systems and is aimed at promoting reusability, modularity, and abstraction.

EXAMPLE OF DISTRIBUTED OBJECT

 

• Let's consider a distributed file system, like the Google File System (GFS). In this system, a file can be represented as an object. 
• Each file object contains metadata such as its name, size, location, and permissions, along with the actual data stored in the file.
• The file object exposes methods for operations such as reading from the file, writing to the file, appending data, deleting the file, etc. 
• These methods can be invoked by clients distributed across the network.

Other Example 

Content Delivery Networks (CDNs): CDNs distribute objects such as web pages, images, and videos across multiple edge servers to reduce latency and improve content delivery speed.

Blockchain Networks: Blockchain platforms distribute objects (blocks) across a network of nodes for decentralized and immutable ledger maintenance. Each block contains transactions and references to previous blocks.

USES OF DISTRIBUTED OBJECT

• 1. to share information across applications or users. 
• 2. to synchronize activity across several machines. 
• 3. to increase performance associated with a particular task.

ADVANTAGE OF DISTRIBUTED OBJECT

• Encapsulation and modularity.
• Improved maintainability and reusability of code.
• Simplified network communication handling.

CHALLENGES OF DISTRIBUTED OBJECT

• Complexity in handling object state and consistency.
• Network latency and failure handling.
• Security and access control issues.

 

DISTRIBUTED FILE SYSTEM

A distributed file system (DFS) allows files to be accessed and processed from multiple hosts sharing via a network. It aims to enable high availability, fault tolerance, and scalability.

EXAMPLES OF DFS

1. Network File System (NFS):
   • Developed by Sun Microsystems, allows a user on a client computer to access files over a network similar to local storage.
2. Andrew File System (AFS):
   • A distributed file system that uses a set of trusted servers to present a homogeneous, location-transparent file name space to all the client workstations.
3. Google File System (GFS):
   • Designed for large data-intensive applications, offering fault tolerance, high aggregate performance, and seamless scalability.
4. Hadoop Distributed File System (HDFS):
   • A part of the Hadoop framework, designed to store large files with streaming data access patterns and run on commodity hardware.

FEATURES OF DFS

• Transparency: Location, access, and replication transparency, making it easier for users to interact with files.
• Scalability: Ability to scale out by adding more machines to the network.
• Reliability and Fault Tolerance: Replication and redundancy to handle failures.
• Consistency and Concurrency Control: Mechanisms to ensure data consistency across the distributed environment.

ADVANTAGES OF DFS

• Users can access files from anywhere in the network.
• Improved data sharing and collaboration.
• Enhanced reliability and availability of data.

CHALLENGES OF DFS

• Ensuring data consistency across distributed nodes.
• Managing network partitioning and reconciling differences.
• Handling concurrent access and maintaining performance.