Computer Networks flashcards, generated for you.

TCP is connection-oriented, reliable, and ordered (3-way handshake); UDP is connectionless, unreliable, and fast. TCP guarantees delivery; UDP does not but has lower latency.

Latency: time for a packet to travel from source to destination (measured in ms). Throughput: amount of data successfully transmitted per unit time (measured in Mbps/Gbps). Trade-off: optimizing one often worsens the other.

Seven-layer conceptual framework (Physical, Data Link, Network, Transport, Session, Presentation, Application) that standardizes network communication. Useful for isolating problems and designing protocols at each layer independently.

Circuit switching: dedicated path reserved end-to-end (predictable but inflexible, used in phones). Packet switching: data split into packets routed independently (efficient, scalable, used in internet). Modern networks use packet switching.

Congestion control prevents network overload by reducing sender transmission rate when packets are lost/delayed. TCP Reno uses Additive Increase Multiplicative Decrease (AIMD): increases window linearly, decreases exponentially on loss.

Bandwidth: maximum throughput a link can theoretically support (e.g., 1 Gbps link). Capacity: actual usable bandwidth after accounting for overhead, interference, and protocols. Capacity ≤ bandwidth always.

Synchronizes sequence numbers between client and server, establishes bidirectional communication, and verifies both parties are reachable. Prevents stale connections and ensures ordered delivery of subsequent data.

Reliable protocols (TCP) require acknowledgments, retransmissions, and ordered delivery—adding overhead and latency. Fast protocols (UDP) skip these checks. Choice depends on application: video streaming tolerates loss (UDP-like); file transfer requires reliability (TCP).

A load balancer distributes incoming network traffic across multiple servers. Solves: prevents single server overload, improves fault tolerance, enables horizontal scaling. Common algorithms: round-robin, least-connections, IP-hash.

Jitter: variation in packet arrival times (latency inconsistency). High jitter breaks real-time apps like VoIP or video conferencing because packets arrive out of sync. Buffering helps but increases end-to-end latency. Trade-off: buffer size vs. responsiveness.