Practical reference material for network engineers. Short enough to scan, detailed enough to use when you're designing, configuring or troubleshooting a network.
Work through network address, broadcast address, usable host range, host counts and subnetting with practical examples.
Understand prefix length, masks, address ranges, longest-prefix matching and the CIDR notation you'll use every day in routing and addressing.
Understand MTU, packet overhead, fragmentation, PMTUD and TCP MSS — with practical encapsulation examples.
The guides focus on the details that matter when you're actually configuring equipment or troubleshooting a path: boundaries, overhead, failure modes and practical calculations.