Computer networks theory of operation has lot of similarities with postal networks. This post briefly describes the similarities between a postal network and a computer network with respect to layering. The Hybrid 5-layer model is considered for comparison purposes.
The diagrams below illustrate the similarities between a postal network and computer network with respect to layering
As seen in the diagram above, postal and computer networks have similar operations in each layer.
- For instance, at the Network layer, each home has a unique postal address and each computer has a unique IP address.
- Also, in postal networks, to uniquely identify an area a ZIP or PIN code is used, whereas in computer networks, to uniquely identify a subnet, the subnetwork identification is used.
- At the transport layer, TCP is similar to registered post (with guaranteed delivery of information without loss) whereas UDP is similar to ordinary post (with best effort delivery with no guarantee on lossless information delivery) etc.
- At the datalink and physical layers, in postal networks letter is carried hop by hop via. vehicles through different paths like road(land), sea, air etc., whereas in computer networks, digital data units are carried hop by hop via. datalink layer protocols like Ethernet, ATM etc. through wired and wireless telecommunication links.