# Q3(a) · Network models

Subject: Computer Networks

Exam: TEE

Reader: https://deep-learning-study-room.vercel.app/cn/#tee/papers/paper-2023-final/q3a

Canonical: https://deep-learning-study-room.vercel.app/read/cn/tee/papers/paper-2023-final--q3a/

Actual paper; 100 marks attempted. Current-syllabus alignment is stated per question.

### Q3(a). Distinguish between peer-to-peer communication and client-server communication. [5 marks]

### Answer

In a **client-server** design, users’ clients contact designated service processes. In **peer-to-peer (P2P)**, participating hosts can supply and consume resources. These are application organizations, not different physical cable types.

Swipe across the diagram to read its labels ↔

![Client-server and peer-to-peer organization](https://deep-learning-study-room.vercel.app/cn/fig/tee-client-peer.a7c6f1b535.svg)

Diagram: Client-server and peer-to-peer organization. Labels: Client-server and peer-to-peer organization | Client-server and peer-to-peer organization | Client-server | Peer-to-peer | Server | C1 | C2 | P1 | P2 | P3 | Peers can supply and consume. A central service can be replicated.

Central service versus cooperating peers.

| Point | Client-server | Peer-to-peer |
| --- | --- | --- |
| Roles | Clients request; designated servers provide services | Peers can both request and provide resources |
| Control | Central policies, accounts and backups are easier to coordinate | Control and copies distributed among peers |
| Performance | Predictable with adequate server capacity; server may bottleneck | Resources grow with peers, but peer capacity/availability vary |
| Scalability | Scale servers, replicas, caching and load distribution | More peers can contribute capacity; coordination becomes harder |
| Reliability | One unreplicated server is a failure point; replication helps | Loss of one peer need not stop system if useful replicas remain |
| Security | Central access control and monitoring | Trust and consistent access policy are harder |
| Best fit | Managed collaboration, databases, login services | Distributed content sharing among participating peers |

## Apply to the platform

Central servers can authenticate users, maintain the authoritative shared document and control versions. The organization must provision capacity, replicate data and avoid a single server failure. P2P can exchange large files or local edits among peers and distribute load, but needs discovery, conflict resolution, trust and availability strategies. A hybrid can keep account control centralized while distributing selected content.

#### Practical example

When three teammates edit one document, a replicated central service can order updates. A peer file swarm can speed distribution only while peers with the needed pieces are available.

**Yaad rakho:** Server mein service central; peers dono roles karte hain.