AP Computer Science Principles Terms Study Guide

AP Computer Science Principles Terms Study Guide protocol - ANSWER-procedure; code of behavior to dictate how the communication should happen and how data gets from one place on the Internet to another. Internet Protocol - ANSWER-(IP) sets the rules for how information is transferred from one computer to another. Routers - ANSWER-makes up the IP connections (web of connected routers/ devices that help send info from one computer to another IP Addresses - ANSWER-required for every device that is directly connected to a TCP/IP network. Always identifies the packet's final destination, even if its on another network. #.#.#.# where each # stands for a number in the range of 0-225 packets - ANSWER-medium in which data is stored. big packet broken down to little packets via Internet. labeled / assigned a packet number os receiving computer can put it back in the right order. (known as TCP or Transmission Control Protocol) ©EMILLECT 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER 2024 Page 2/10 port - ANSWER-a number which is assigned by TCP to indicate what type of internet service the data should be used for. EX: SMTP (email) uses port 25, while HTTP (normal web browsing) uses port 80 TCP - ANSWER-the data created into packets, which are then given a port/ packet number. IP adds destination and return address. Go through routers to destination routing table - ANSWER-Routers are programmed with instructions about where to send each packet of data, depending on the destination's IP address. These instructions are often stored in a routing table. Routers can judge, based on the initial digits of an IP address, which direction packets need to be sent. the router just sends the packet one step closer to the destination, and lets the next router take care of the rest. Domain name system - ANSWER-(DNS) A large database of unique IP addresses that correspond with domain names Dynamic Host Configuration Protocol - ANSWER-helps to assign each device an IP address. When computers connect to a network, they will connect to a DHCP server. The DHCP server is able to access a pool of available IP addresses, and the server is responsible for assigning each computer on the network a unique IP address. ©EMILLECT 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER 2024 Page 3/10 devices on the Internet are able to receive their own IP, and determine which IP address corresponds to the website that a user is trying to visit. domain - ANSWER-just an identifier like "" or "", when a user types a URL into a web browser, the computer contacts a DNS server, which stores information about which domain names map to which IP addresses. There are many DNS servers, and not all of them will always be updated at the same time when there are new changes to which domain names map to which IP addresses. DNS tree hierarchy - ANSWER-Root-->com/net-->google/facebook/cs50--> images/ maps IPv4 - ANSWER-- 32-bit decimal network addressing standard meaning that there can be at most 2^32 addresses under IPv4. With individual 8 bit numbers consists of 4 n