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Practical Packetry guides for engineers, students, and anyone who wants clearer networking fundamentals.
May 8, 2026
Understanding MTU, MSS, and Packet Fragmentation
Learn how Maximum Transmission Unit (MTU) and Maximum Segment Size (MSS) affect network performance. Covers fragmentation, Path MTU Discovery, tunnel overhead, and how to troubleshoot MTU issues.
April 17, 2026
Wildcard Mask Explained: How Routers Really Match Addresses
Learn what wildcard masks are, how they relate to subnet masks, and why Cisco routers use them in ACLs and OSPF. Binary inversion explained step by step.
April 4, 2026
CIDR Notation Explained: Prefix Lengths, Masks, and Host Counts
Understand CIDR notation, how prefix lengths map to subnet masks, and how to estimate host capacity quickly.
April 1, 2026
Subnetting Basics: A Practical Guide to IP Subnetting
Learn how IP subnetting works, including CIDR notation, subnet masks, and how to calculate network and host addresses.