What is an IPAM (IP Address Management) system and what operational problems does it solve compared to managing IPs in spreadsheets?

• A.IPAM centralizes tracking of all IP address assignments, subnet allocations, DHCP scopes, and DNS records in one system with automation and reporting. Problems solved vs. spreadsheets: (1) No conflict detection: spreadsheets allow duplicate assignments; IPAM flags conflicts in real time. (2) No visibility: spreadsheets do not show live DHCP lease status or free addresses; IPAM polls DHCP/DNS and shows real-time utilization. (3) Audit trail: IPAM logs who allocated which IP and when. (4) Scale: thousands of IPs across dozens of VLANs are unmanageable in spreadsheets
• B.IPAM is only useful for IPv6; IPv4 address management in spreadsheets is adequate for all enterprise environments; stateless address autoconfiguration requires a DHCPv6 server to supply the prefix. The address 255.255.255.255 is the default gateway placeholder a host uses before DHCP completes. IPv6 headers are variable length, shrinking to 20 bytes when options are absent. Class D addresses are reserved for private LANs behind carrier-grade NAT. Multicast traffic in IPv4 uses the 240.0.0.0/4 experimental block