Networking Primer – Part 5.3: Network Layer – IP Routing

Map of The Internet

Previous: Networking Primer – Part 5.2: Network Layer – DNS and DHCP

Up until this point, all of the layers, addresses and other attributes we have discussed have conceptually existed inside either the source or destination node. We now need a mechanism for physically moving the data from point A and B. While it is possible and would provide a very simple solution to delivering data, having a single connection between each source and destination node isn’t feasible. This might be appropriate for a test system in a lab where we could use a cross-over cable to connect two computers together, but we would face insurmountable challenges if we tried to connect the billions of devices in the world together with one-to-one connections. We need to split down our global network into smaller interconnect pieces and it is at this point we introduce additional devices outside of the nodes that will […]

Networking Primer – Part 5.1: Network Layer – IP Addressing

Image of 3D IP Address

Previous: Networking Primer – Part 4: Transport Layer, TCP and UDP

The clue might be in the title, but the Network Layer is one of the more important layers in the network stack. So far we have defined high-level identities, application services and data formats. We have also established our protocols, chopped up data into smaller more manageable pieces and tagged them with a sequence number. It is at this point we need to start defining more details on where we will be sending the data and moving closer to establishing a unique address for both source and destination. We also need network components to be in place to allow us to transmit and route the data appropriately.

The two core concepts at work in this layer are addressing and routing.

Addressing: Internet Protocol (IP)

The most ubiquitous protocol used for network […]