AP CSP IP Addresses and DNS
38 flashcards covering AP CSP IP Addresses and DNS for the AP-CS-PRINCIPLES Big Idea 4 section.
The topic of IP addresses and Domain Name System (DNS) is a fundamental aspect of computer networking covered in the AP Computer Science Principles curriculum, specifically under Big Idea 4. This section addresses how devices communicate over the internet, including the roles of IP addresses in identifying devices and the function of DNS in translating human-readable domain names into IP addresses. Understanding these concepts is essential for grasping how data is transmitted across networks.
On practice exams and competency assessments, questions about IP addresses and DNS often involve multiple-choice formats or scenario-based problems that require students to apply their knowledge to real-world situations. A common pitfall is confusing public and private IP addresses or misunderstanding how DNS resolution works, which can lead to incorrect answers. It's important to remember that while IP addresses are unique identifiers, DNS is a crucial intermediary that simplifies user navigation on the internet. A practical tip often overlooked is the importance of checking DNS settings when troubleshooting connectivity issues, as misconfigurations can lead to significant access problems.
Terms (38)
- 01
What is the purpose of DNS?
The Domain Name System (DNS) translates human-readable domain names into IP addresses, allowing browsers to load Internet resources. This system is essential for navigating the web effectively (College Board AP CED).
- 02
How does a DNS resolver function?
A DNS resolver is responsible for receiving a query from a client and then performing the necessary lookups to return the corresponding IP address of a domain name (College Board AP CED).
- 03
What is an IP address?
An IP address is a unique identifier assigned to each device connected to a network that uses the Internet Protocol for communication. It serves two main functions: identifying the host or network interface and providing the location of the device in the network (College Board AP CED).
- 04
What is the difference between IPv4 and IPv6?
IPv4 uses a 32-bit address scheme allowing for about 4.3 billion unique addresses, while IPv6 uses a 128-bit address scheme, significantly increasing the number of available addresses to accommodate the growing number of devices (College Board AP CED).
- 05
How often must DNS records be updated?
DNS records should be updated whenever there is a change in the associated IP address or domain name. However, there is no strict frequency; updates depend on the specific needs of the domain (College Board AP CED).
- 06
What is a static IP address?
A static IP address is an IP address that does not change. It is manually assigned to a device and remains constant, making it easier to reach that device consistently (College Board AP CED).
- 07
What is a dynamic IP address?
A dynamic IP address is assigned by a DHCP server and can change over time as devices connect and disconnect from the network. This allows for more efficient use of IP addresses (College Board AP CED).
- 08
What is the role of a DNS server?
A DNS server stores DNS records and responds to queries from clients to resolve domain names into IP addresses, facilitating communication over the Internet (College Board AP CED).
- 09
When a user types a URL into a browser, what is the first step?
The browser sends a DNS query to resolve the domain name into an IP address, allowing it to locate the server hosting the requested resource (College Board AP CED).
- 10
What does the term 'TTL' mean in DNS?
TTL stands for Time To Live, which is a setting that indicates how long a DNS record should be cached by a resolver before it must be refreshed (College Board AP CED).
- 11
What is the function of a DNS cache?
A DNS cache temporarily stores DNS query results to speed up subsequent requests for the same domain name, reducing the need for repeated lookups (College Board AP CED).
- 12
What happens when a DNS query fails?
If a DNS query fails, the client may receive an error message indicating that the domain name could not be resolved, and the user may be unable to access the desired website (College Board AP CED).
- 13
What is a domain name?
A domain name is a human-readable address used to identify a location on the Internet, which is translated into an IP address by DNS (College Board AP CED).
- 14
What is the significance of the 'A' record in DNS?
The 'A' record maps a domain name to its corresponding IPv4 address, allowing users to access the website associated with that domain (College Board AP CED).
- 15
What is a CNAME record?
A CNAME (Canonical Name) record allows one domain name to be an alias for another, enabling multiple domain names to point to the same IP address (College Board AP CED).
- 16
What is the role of the root DNS servers?
Root DNS servers are the highest level of DNS servers that store information about top-level domains and help direct queries to appropriate DNS servers (College Board AP CED).
- 17
How does DNS load balancing work?
DNS load balancing distributes incoming traffic across multiple servers by returning different IP addresses for the same domain name, improving performance and reliability (College Board AP CED).
- 18
What is the purpose of a reverse DNS lookup?
A reverse DNS lookup translates an IP address back into a domain name, which can be useful for troubleshooting and verification purposes (College Board AP CED).
- 19
What is a subnet mask?
A subnet mask is a 32-bit number that divides an IP address into network and host portions, determining which part of the address identifies the network and which part identifies the device (College Board AP CED).
- 20
What does NAT stand for and what is its purpose?
NAT stands for Network Address Translation, which allows multiple devices on a local network to share a single public IP address for accessing the Internet (College Board AP CED).
- 21
What is the function of DHCP in IP address assignment?
DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses to devices on a network, simplifying network management (College Board AP CED).
- 22
What is the purpose of an IP address in data transmission?
An IP address identifies the source and destination of data packets, ensuring that information is sent to the correct device across the network (College Board AP CED).
- 23
What is the difference between public and private IP addresses?
Public IP addresses are accessible over the Internet, while private IP addresses are used within local networks and are not routable on the Internet (College Board AP CED).
- 24
What is a DNS zone?
A DNS zone is a distinct part of the DNS namespace that is managed by a specific organization or administrator, containing DNS records for that zone (College Board AP CED).
- 25
What is the purpose of a PTR record in DNS?
A PTR (Pointer) record is used for reverse DNS lookups, linking an IP address to a domain name (College Board AP CED).
- 26
What does the term 'DNS spoofing' refer to?
DNS spoofing is a malicious attack where incorrect DNS records are inserted into a DNS resolver's cache, redirecting users to fraudulent websites (College Board AP CED).
- 27
What is the function of the 'MX' record in DNS?
The 'MX' (Mail Exchange) record specifies the mail server responsible for receiving email on behalf of a domain, directing email traffic appropriately (College Board AP CED).
- 28
What is the purpose of a DNS query?
A DNS query is a request sent by a client to a DNS server to resolve a domain name into its corresponding IP address (College Board AP CED).
- 29
What is the role of a DNS registrar?
A DNS registrar is an organization that manages the reservation of Internet domain names and maintains the associated DNS records (College Board AP CED).
- 30
What is the significance of an IP address in network security?
An IP address can be used to identify and track devices on a network, playing a crucial role in implementing security measures such as firewalls and access controls (College Board AP CED).
- 31
What is an authoritative DNS server?
An authoritative DNS server contains the complete DNS records for a domain and provides definitive answers to queries about that domain (College Board AP CED).
- 32
What is the purpose of a DNS forwarder?
A DNS forwarder is a DNS server that forwards queries to other DNS servers, typically used to reduce the load on a local DNS server (College Board AP CED).
- 33
What is the function of the 'SOA' record in DNS?
The 'SOA' (Start of Authority) record provides information about a DNS zone, including the primary name server and the email of the zone administrator (College Board AP CED).
- 34
What is the purpose of a DNS lookup?
A DNS lookup is the process of querying a DNS server to obtain the IP address associated with a domain name (College Board AP CED).
- 35
What does the term 'domain hierarchy' refer to in DNS?
Domain hierarchy refers to the structured organization of domain names in the DNS system, where each level of the hierarchy is separated by dots (College Board AP CED).
- 36
What is the role of a secondary DNS server?
A secondary DNS server provides redundancy and load balancing by maintaining a copy of the DNS records from the primary server (College Board AP CED).
- 37
What is the purpose of a DNS zone transfer?
A DNS zone transfer is the process of copying DNS records from a primary DNS server to a secondary server, ensuring consistency between the two (College Board AP CED).
- 38
What does the term 'IP address exhaustion' mean?
IP address exhaustion refers to the depletion of available IP addresses, particularly in IPv4, due to the increasing number of devices connected to the Internet (College Board AP CED).