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Networking

Big picture: one drawing of the home network, then a VPC as its own address space, then the rewrite at the edge, then how the prefixes are written. Names come after, because a name is only useful once an address has somewhere to go.

Follow a packet

  1. The network: interfaces, the next hop, and a container, on one drawing.
  2. VPC: the same ideas as an address space in AWS. The instance is a machine on one subnet inside it.
  3. NAT: at the public boundary the router rewrites the private source, and remembers how, so the reply can come back.
  4. CIDR: how the prefixes in those tables are written. Read this once /24 and /16 need unpacking.

After you have an address

DNS turns a name into the address the packet was following.

These two use a connection. Each stands on its own.

  • SSH: a tunnel and a remote shell.
  • RPC vs REST: two styles of calling another service.
  • VPC inventory: gateways, route tables, and the addresses AWS reserves, after the VPC page.
  • Route 53: DNS, as AWS runs it.