DNS (Domain Name System) in Computer Networks - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify the primary purpose of DNS.

Computer Networks

The main function of DNS is to translate [1] names into IP addresses.

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Anumeric

Bdomain

Chardware

Dprotocol

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing domain names with IP addresses

Thinking DNS translates hardware names

DNS converts domain names like example.com into IP addresses computers use to communicate.

2fill in blank

medium

Complete the code to show the DNS record type used for mapping domain names to IP addresses.

Computer Networks

The DNS record type that maps a domain name to an IPv4 address is called an [1] record.

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AA

BTXT

CCNAME

DMX

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing MX which is for mail servers

Choosing CNAME which is for aliases

An A record in DNS links a domain name to its IPv4 address.

3fill in blank

hard

Fix the error in the explanation about DNS caching.

Computer Networks

DNS caching helps reduce [1] by storing previous query results temporarily.

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Abandwidth

Berrors

Clatency

Dsecurity

Attempts:

3 left

💡 Hint

Common Mistakes

Thinking caching reduces errors

Confusing bandwidth with latency

DNS caching reduces latency by avoiding repeated lookups for the same domain.

4fill in blank

hard

Fill both blanks to complete the DNS query process description.

Computer Networks

When a DNS resolver receives a query, it first checks its [1] cache and if not found, it queries the [2] DNS server.

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Alocal

Broot

Cauthoritative

Dglobal

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing authoritative with root server

Thinking global cache is checked first

The resolver checks its local cache first, then queries the root DNS server if needed.

5fill in blank

hard

Fill all three blanks to complete the DNS record comprehension example.

Computer Networks

records = { [1]: [2] for [3] in dns_data if dns_data[[3]]['type'] == 'A' }

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Adomain

Bip_address

Crecord

Drecord['name']

Attempts:

3 left

💡 Hint

Common Mistakes

Using record['name'] as key without defining record

Mixing up keys and values

This comprehension creates a dictionary mapping domain names to IP addresses for A records.