Module 5 – Network Protocols (Vocabulary Flashcards)

A collection of key vocabulary terms and definitions from Cisco CyberOps Associates Module 5: Network Protocols.

Network Protocol

A set of rules that governs message encoding, formatting, timing, and delivery between devices on a network.

TCP/IP Protocol Suite

Open, standards-based collection of protocols used for modern internetwork communication, including the Internet.

Host (End Device)

Any computer or device that participates directly in network communications.

Server

A host running specialized software to provide services (e.g., web, email, file) to other devices on the network.

Client

A host running software that requests and displays information obtained from servers.

Peer-to-Peer Network

A small network in which devices can act simultaneously as both clients and servers without dedicated server hardware.

SOHO Network

Small Office/Home Office network that links a remote or home office to corporate resources or the Internet.

Internet Service Provider (ISP)

Company that provides individuals and organizations access to the Internet and related services.

Tier 1 ISP

Global provider that forms the Internet backbone and peers with other Tier 1 networks at IXPs.

Tier 2 ISP

Regional provider that connects to Tier 1 networks at exchange points and sells service to smaller ISPs or organizations.

Tier 3 ISP

Local provider that delivers Internet connectivity to homes and small businesses via a Point of Presence (PoP).

Internet Exchange Point (IXP)

Facility where multiple ISPs interconnect their networks to exchange Internet traffic.

Point of Presence (PoP)

Physical location where an ISP provides access for customers to connect to its network.

Traceroute

Utility that traces the path packets take to a destination, listing each hop along the route.

Hypertext Transfer Protocol (HTTP)

Application-layer protocol for transferring web pages and other resources over the World Wide Web.

HTTP Secure (HTTPS)

Encrypted version of HTTP that protects data exchanged between web clients and servers.

Representational State Transfer (REST)

Web-service architectural style that uses HTTP methods and APIs to create web applications.

Domain Name System (DNS)

Protocol/service that translates domain names into their corresponding IP addresses.

Dynamic Host Configuration Protocol (DHCPv4)

Protocol that dynamically assigns IPv4 addresses and related information to hosts at startup.

DHCPv6

IPv6 version of DHCP that dynamically assigns IPv6 addressing information to hosts.

Stateless Address Autoconfiguration (SLAAC)

IPv6 method allowing a device to self-configure its address without a DHCPv6 server.

Simple Mail Transfer Protocol (SMTP)

Protocol that enables clients to send email to servers and servers to relay email between themselves.

Post Office Protocol v3 (POP3)

Protocol that allows clients to retrieve and download email from a mail server.

Internet Message Access Protocol (IMAP)

Protocol that lets clients access and manage email stored on a server while keeping mail on the server.

File Transfer Protocol (FTP)

Protocol that allows users to transfer files between hosts across a network.

SSH File Transfer Protocol (SFTP)

Secure, encrypted version of FTP that operates over SSH.

Trivial File Transfer Protocol (TFTP)

Simple, connectionless protocol for basic file transfer with best-effort delivery.

Transmission Control Protocol (TCP)

Connection-oriented transport-layer protocol providing reliable, acknowledged data delivery.

User Datagram Protocol (UDP)

Connectionless transport-layer protocol that sends packets without guaranteed delivery.

Internet Protocol version 4 (IPv4)

Network-layer protocol using 32-bit addresses to route packets end-to-end.

Internet Protocol version 6 (IPv6)

Successor to IPv4, using 128-bit addresses for vastly larger address space.

Network Address Translation (NAT)

Technique that converts private IPv4 addresses to public addresses for Internet communication.

ICMPv4

Messaging protocol that provides error and status information for IPv4 packet delivery.

ICMPv6

IPv6 equivalent of ICMPv4, providing error messaging and diagnostics for IPv6.

ICMPv6 Neighbor Discovery (ND)

Set of ICMPv6 messages used for address resolution and duplicate address detection.

Open Shortest Path First (OSPF)

Open-standard, link-state interior routing protocol that uses areas in a hierarchical design.

Enhanced Interior Gateway Routing Protocol (EIGRP)

Cisco proprietary routing protocol that uses a composite metric of bandwidth, delay, load, and reliability.

Border Gateway Protocol (BGP)

Exterior gateway routing protocol used between ISPs to exchange routing information across the Internet.

Address Resolution Protocol (ARP)

Protocol that maps IPv4 addresses to their corresponding hardware (MAC) addresses on a local network.

Ethernet

Set of data-link and physical-layer standards defining wiring, signaling, and frame formats for wired LANs.

Wireless LAN (WLAN)

Standards-based protocol (802.11) defining wireless signaling over 2.4 GHz and 5 GHz frequencies.

Encapsulation

Process of adding protocol headers (and trailers) to data as it moves down the protocol stack for transmission.

De-encapsulation

Process by which the receiving device removes protocol headers as data moves up the stack.

Protocol Data Unit (PDU)

Generic term for the form data takes at each OSI or TCP/IP layer during encapsulation.

Segment (TCP) / Datagram (UDP)

Transport-layer PDU carrying application data plus TCP or UDP header information.

Packet

Network-layer PDU containing transport-layer data plus an IP header.

Frame

Data-link-layer PDU containing a packet plus link-layer header and trailer information.

Bits

Physical-layer representation of data as electrical, optical, or radio signals transmitted across media.

Segmentation

Dividing large data streams into smaller pieces (packets) for efficient network transmission.

Multiplexing

Interleaving multiple conversations over the network simultaneously by sharing bandwidth.

Sequencing

Transport-layer function (mainly TCP) that numbers segments so they can be reassembled in order.

Flow Control

Mechanism that manages the rate of data transmission between sender and receiver to prevent overload.

Response Timeout

Specified period a device waits for a reply before taking corrective action or retransmitting.

Access Method

Rule that determines when a device may transmit on a shared medium (e.g., CSMA/CA in WLANs).

Unicast

One-to-one message delivery from a single sender to a single receiver.

Multicast

One-to-many message delivery from one sender to a selected group of receivers.

Broadcast

One-to-all message delivery where all hosts on a network segment receive the message simultaneously.

Layered Model

Concept of dividing network functions into hierarchical layers to simplify design and interoperability.

OSI Reference Model

Seven-layer conceptual framework that standardizes functions of a telecommunications or computing system.

TCP/IP Model

Four-layer framework that describes TCP/IP protocol suite operations (Network Access, Internet, Transport, Application).

Wireshark

Packet-sniffer application used to capture and analyze network traffic for troubleshooting and education.

Cloud Service (Medical Example)

Centralized Internet-accessible storage and application platform enabling secure sharing of medical data like X-rays.