Chapter 15: Networking in the Cloud: DNS, Load Balancing, and IP Addressing

1. B. The A record is used to map a domain name to an IPv4 address, so option B is correct. Option A is incorrect because the AAAA record is used for IPv6 addresses. Option C is incorrect; NS is a name server record. Option D is incorrect; SOA is a start of authority record.
2. A. DNSSEC is a secure protocol designed to prevent spoofing and cache poisoning, so option A is correct. Options B and C are incorrect because SOA and CNAME records contain data about the DNS record; they are not an additional security measure. Option D is incorrect because deleting a CNAME record does not improve security.
3. A. The TTL parameters specify the time a record can be in a cache before the data should be queried again, so option A is correct. Option B is incorrect; this time period is not related to timeouts. Option C is incorrect; the TTLs are not related to time restriction on data change operations. Option D is not correct; there...