Introduction to Computer Networks and Layered Models

Vocabulary practice flashcards covering fundamental networking concepts, geographical network classifications, layered models (OSI and TCP/IP), encapsulation, and IP addressing.

Network

Multiple computers that are connected and can share information and resources.

WAN

Wide Area Network; a network spanning over a large geographical area.

LAN

Local Area Network; a network covering a small geographical area.

MAN

Metropolitan Area Network; a network designed to cover a metropolitan area.

PAN

Personal Area Network; a short-range network established around a person.

Networking Paradigms

Network-based computing models and architectures, including websites, cloud computing, IoT, and high-performance computing.

Importance of Networks in Computing

The consideration that networking issues can cause correct and efficient code to misbehave or work slowly.

Internet

A network of networks managed by ISPs (Internet Service Providers).

Internet Protocols

Standardisations and rules governing communications over networks.

OSI Model

A $7$-layer network architecture model consisting of: 7. Application, 6. Presentation, 5. Session, 4. Transport, 3. Network, 2. Data link, and 1. Physical.

TCP/IP Model

A four-layer layered network model consisting of Application, Transport (host-to-host), Internet (network layer), and Link (network access layer).

Layered Model Abstraction

An architectural principle operating irrespective of underlying hardware and topology, enabling applications to talk to one another and hosts to talk to one another.

End-to-End Concept

The design principle stating that the network is responsible for providing transparent, best-effort connections, while end hosts are responsible for reliability and security.

Layer Encapsulation

The process where each layer in the TCP/IP stack adds its own header to data, which becomes the payload for the next lower layer (e.g., Data is packaged into UDP data with a UDP header, then IP data with an IP header, and finally Frame data with a Frame header and Frame footer).

Network Access Layer

The TCP/IP layer that deals with the local link a host is connected to, where each host has a link-unique address (such as a $48\text{-bit}$ MAC address).

MAC Address

A link-unique $48\text{-bit}$ hardware address used by hosts on their local network access layer link.

Internet Layer

The layer responsible for next-hop routing, unique addressing, passing received packet payloads to the correct transport layer, facilitating connection of different types of networks, and providing 'best effort' packet delivery.

IPv4

An Internet layer addressing protocol dating from $1981$ that uses $32\text{ bits}$ written in octet-grouped dotted-decimal format, providing approximately $4.3\text{ billion}$ addresses.

IPv6

An Internet layer addressing protocol that utilizes $128\text{ bits}$ of address space.