Network architectures shape how applications communicate and share resources. Client-server and peer-to-peer are two main approaches, each with unique strengths. Client-server centralizes control, while peer-to-peer distributes responsibilities across nodes.
Implementing these architectures involves choosing programming languages, protocols, and handling communication logic. Evaluating performance considers scalability, reliability, and efficiency. Techniques like load testing and monitoring help assess real-world behavior.
Client-Server Architecture
Client-server vs peer-to-peer architectures
- Client-server architecture utilizes a centralized structure where dedicated servers provide services to clients
- Clients send requests to servers which process the requests and send responses back (web browsing with HTTP, email with SMTP/IMAP/POP3, file transfer with FTP)
- Centralized control and management makes it easier to implement security measures
- Scalability achieved through vertical scaling by upgrading server hardware
- Single point of failure (server) and potential bottlenecks due to centralized processing
- Higher cost of maintaining dedicated servers
- Peer-to-peer (P2P) architecture employs a decentralized structure where each node acts as both a client and a server
- Nodes directly communicate with each other without requiring a central server (file sharing with BitTorrent, instant messaging with Skype/Discord, distributed computing with Folding@home/SETI@home)
- No single point of failure and reduced infrastructure costs by not needing dedicated servers
- Scalability achieved through horizontal scaling by adding more nodes
- Complexity in managing and coordinating nodes along with security challenges due to decentralized nature
- Inconsistent performance due to varying node capabilities
Pros and cons of network architectures
- Client-server advantages include centralized control and management, easier implementation of security measures, and scalability through vertical scaling (upgrading server hardware)
- Client-server disadvantages include having a single point of failure (server), higher cost of maintaining dedicated servers, and potential bottlenecks due to centralized processing
- Peer-to-peer advantages include no single point of failure, reduced infrastructure costs by not needing dedicated servers, and scalability through horizontal scaling (adding more nodes)
- Peer-to-peer disadvantages include complexity in managing and coordinating nodes, security challenges due to decentralized nature, and inconsistent performance due to varying node capabilities
Implementing and Evaluating Architectures
Implementation of network applications
- Client-server implementation involves choosing a programming language (Python, Java, C++), implementing server-side logic to handle client requests, implementing client-side logic to send requests and process responses, and using appropriate protocols (HTTP, TCP, UDP) for communication
- Peer-to-peer implementation involves choosing a programming language (Python, Java, C++), implementing node logic to handle both client and server functionality, using appropriate protocols (BitTorrent, Kademlia) for communication, and implementing mechanisms for node discovery and data exchange
Performance of network architectures
- Scalability evaluation assesses the ability to handle increasing number of clients or nodes, considering vertical scaling for client-server and horizontal scaling for P2P
- Reliability evaluation assesses the impact of node or server failures on the overall system, considering fault tolerance mechanisms like redundancy and replication
- Performance evaluation measures response times, throughput, and latency while considering the impact of network conditions (bandwidth, latency) and assessing the efficiency of resource utilization (CPU, memory)
- Evaluation techniques include:
- Simulation and modeling
- Load testing and stress testing
- Monitoring and profiling of real-world deployments