The Laserblasted Kickstarter is still going so technically, I ought to share a snippet from that. It’s the last chance for that to be a work-in-progress. Instead, here’s a bit from the new Networking for System Administrators.
These common transport protocols all run over IPv4 and IPv6 alike. Each has minor updates to match the underlying IP stack, but the basic concepts such as port numbers and connection state remain unchanged. Most differences are only visible if you analyze packet headers.
A single chunk of TCP, UDP, or ICMP data is called a segment. Each segment gets wrapped in an IPv4 or IPv6 packet, which is then wrapped in a datalink frame and sent out into the cold hard world. The word segment isn’t used very often. Instead you’ll see references to a UDP or TCP packet, which means an individual segment wrapped in an IP packet. The IP packet contains vital information, like the source and destination IP addresses. Think of a segment like a fast-food hamburger in wax paper. If a cashier dropped a fresh hot burger, unwrapped, straight in your hand, you’d consider it incomplete.
Networking for System Administrators is open for sponsorships. And the Laserblasted Kickstarter closes early next week. I’d appreciate your support on either.