Compare and contrast networking models

Client–Server Model

A centralized model where a server hosts and manages resources, and a client makes requests. Communication follows a request/response pattern; the server acts as the single point of access.

Advantages & Disadvantages

Aspect	Advantage	Disadvantage
Control	Easier to enforce policies, manage resources, ensure data consistency	Poor server management degrades performance for everyone
Scalability	Can scale by upgrading or adding servers	Scaling requires significant investment in infrastructure
Security	Centralized security is easier to administer	Servers are attractive targets for cyberattacks
Efficiency	Servers can be optimized for specific workloads	High demand can cause bottlenecks and reduced performance
Reliability	High uptime with proper infrastructure	Server = single point of failure; if it goes down, everyone’s affected

Real-World Examples

• Web browsing — browser (client) requests data from a web server
• Email (e.g. Outlook + Exchange) — centralized control over security and storage, but a single point of failure
• Banking apps — transactions processed on central servers; consistent and secure, but a high-value attack target

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Peer-to-Peer (P2P) Model

A decentralized model where every participant (peer) is both a client and a server. No dedicated central server — peers share resources and services directly with each other.

Used in: file-sharing networks, blockchain, certain messaging systems.

Advantages & Disadvantages

Aspect	Advantage	Disadvantage
Control	No central authority → resilient, no single point of failure	Problems are hard to trace; usage metrics difficult to gather
Scalability	More peers = more resources and compute, at minimal cost	Performance varies depending on peer count and capacity
Security	Anonymity can be a feature	Anonymity enables malware and unethical software distribution
Efficiency	Resources distributed across peers, reducing individual load	Inefficient management can cause redundancy and overhead
Reliability	Network keeps running even if some peers drop off	Transient peers can compromise data availability

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Key Contrast

	Client–Server	Peer-to-Peer
Architecture	Centralized	Decentralized
Authority	Dedicated server	Distributed among peers
Resilience	Low (single point of failure)	High (no single point of failure)
Security control	Easier to manage	Harder to enforce
Cost to scale	High	Low