A comprehensive, CCNA-focused guide to Network Address Translation — why NAT exists, the four address terms (inside local, inside global, outside local, outside global) made memorable, the three flavors (static NAT, dynamic NAT, and PAT/overload) with real Cisco IOS configuration and verification, the inside/outside interface gotcha that breaks every first attempt, how to troubleshoot with show ip nat translations and debug, and NAT's bigger-picture role: the security myths, broken end-to-end connectivity, carrier-grade NAT, NAT64, and how IPv6 changes the story. Built around exam topic 4.6 with commands you can lab.
Subnetting
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Network Address Translation (NAT): A CCNA-Focused Guide -
IP Address Management (IPAM): A CCNA-Focused Guide A comprehensive, CCNA-focused guide to IP Address Management — what IPAM is, the IPv4 address space and RFC 1918 you have to manage, subnetting and VLSM worked the way the exam expects, DHCP (the DORA process, Cisco IOS server and ip helper-address relay config), DNS record types, IPv6 addressing (global unicast, link-local, EUI-64, SLAAC vs DHCPv6), and how real IPAM is done with spreadsheets, phpIPAM, NetBox, and full DDI platforms like Infoblox. Built around the 200-301 IP Connectivity and IP Services domains, with real config and address plans.
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Subnetting Explained: Why Subnet Masks Aren't Just 255s and 0s A from-intuition walk through subnetting, and a direct answer to the question every beginner eventually asks: would you ever use a subnet mask octet that isn't 255 or 0? Yes — constantly — and here is exactly when and why.
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CCNA: IPv4 Addressing and Subnetting A complete guide to IPv4 addressing and subnetting for CCNA — binary conversion, CIDR, subnet masks, the magic number method that works under exam pressure, VLSM design, and route summarization with fully worked examples.