Understanding Network Components and Protocols
NETWORK: A network consists of multiple computers connected using a communication system. Its aim is to communicate and share files. INTERNET: A public access network consisting of interconnected computer networks that transmit data using Internet Protocol (IP). DATA NETWORKS: Digital networks are used to send data between PCs. SERVER: Equipment that serves as a focal point in a client/server model, providing services to network clients. For example: DNS, DHCP, file storage, applications, websites, etc. WIKI: A website in which visitors can add, modify, and delete content, such as Wikipedia. PODCASTING: A media file or files distributed through syndication for playback on portable devices. EXTRANET: A part of the Internet that extends outside the company. INTRANET: An organization’s internal system, a website accessible only to internal employees or students, either internally or remotely. ROUTER: A network layer device that uses one or more metrics to determine the optimal route through which network traffic must be sent. It takes packets and sends them based on information from the network layer. TCP/IP: A protocol that controls transmission over the Internet. ROUTING: The process of finding a route to the destination host. PACKAGE: A logical grouping of information that includes a header containing control information and user data. STREAM: Data streaming from one location to another. For example, real-time video is downloaded while watching. QoS: Quality of Service allows the establishment of queue management strategies that prioritize different classifications of data applications. HASH ALGORITHM: A reproducible method of converting data types into small numbers, serving as fingerprints for data. CHECKSUM: A form of redundancy check, a simple way to protect the integrity of data by detecting errors in data sent over time or space. MULTIPLEXING: A process that combines multiple streams of digital data into a single signal. ENCAPSULATION: The process by which data is wrapped in a particular protocol header. SEGMENTATION: The division of communication into parts. SWITCH: A network device that filters, forwards, or floods frames based on the destination address of each frame. It operates in the data-link layer of the Open Systems Interconnection (OSI) model. DISP. INTERMEDIATE: Connects directly with end-user devices and provides routing to other networks. ADDRESS HOST: Usually refers to the network layer address. HOST: A device that communicates over a network. ENCODING: The process that converts information into symbols for communication. LAN (Local Area Network): Interconnected local networks that are under scrutiny. TOPOLOGY LOGIC: A map of the devices on a network and how they communicate with each other, showing the flow of data in a network. HTTP (Hypertext Transfer Protocol): A common protocol that governs how a server interacts with a web client. TCP (Transmission Control Protocol): A transport protocol that manages individual conversations between web servers and web clients. HTTP TCP messages are divided into small parts called segments for the client stations. IP (Internet Protocol): Responsible for formatting TCP segments into packets, assigning the correct address, and selecting the best route to the destination host. SUITE: A group of components that work cooperatively. For example, TCP/IP protocols work together to provide communication between networks of PCs. Benefits of Using a Layered Model: The layered model shows the operation of the protocols that occur within each layer, as well as the interaction of the layers above and below it. The benefits include:
- Assists in protocol design, ensuring that protocols operating in a specified layer have definite information and a defined interface according to the layers above and below.
- Encourages competition, allowing products from different vendors to work together.
- Prevents changes in technology or capabilities of a layer from affecting other layers.
- Provides a common language to describe features and network capabilities.
RFCs: Documents available to the public (Requests for Comments) that contain formal specifications of communication protocols and resources describing the use of protocols. FOUR LAYERS:
- APPLICATION: Represents data for the user with more control and dialogue coding.
- TRANSPORTATION: Supports communication between different devices on different networks.
- INTERNET: Determines the best route through the network.
- ACCESS NETWORK: Controls how devices and means form the network.