Computer Networks
According to Wikipedia:
A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. These interconnections are made up of telecommunication network technologies, based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies.
Internet Protocol (IP)
Note: Read more at Internet Protocol Suite (TCP/IP)
The Internet Protocol (IP) is the principal communications protocol being used on the Internet. As part of the OSI model, IP is the network layer protocol, or layer 3 protocol, in the Internet protocol suite. Devices form a network based on an IP address. Which is a 32-bit number that is used to identify a device on a network, at least when it comes to IPv4. In the future IPv6 will be used, which is a 128-bit number. NAT or Network Address Translation is used to translate the IP address of an internal network to an external IP address, which expands the number of available IP addresses on the Internet.
Application Layer Protocols
HTTP
HTTP is by far the most used application layer protocol on the Internet.
Publish-Subscribe Pattern
Note: See the Publish Subscribe Pattern for more details.
In software architecture, publish–subscribe is a messaging pattern where senders of messages, called publishers, do not program the messages to be sent directly to specific receivers, called subscribers, but instead categorize published messages into classes without knowledge of which subscribers, if any, there may be. Similarly, subscribers express interest in one or more classes and only receive messages that are of interest, without knowledge of which publishers, if any, there are.
One of the benefits of the publish/subscribe model vs. the request/response model of HTTP and REST, is that it doesn't rely on a reliable connection. Clients can connect and disconnect randomly and the queue of the broker will manage flushing of the queue by delivering the message when it can.
Message Queue
Note: See the Message Queue Pattern Notes for more details.
In computer science, message queues and mailboxes are software-engineering components typically used for inter-process communication (IPC), or for inter-thread communication within the same process. They use a queue for messaging – the passing of control or of content. Group communication systems provide similar kinds of functionality.
Message Queue Implementations
Here are some of the dominant Message Queue implementations:
Message Queues and Internet of Things
The Internet of Things takes these kinds of message queuing networks and applies it to create vast networks of low power and simpler devices to communicate with each other and traditional servers.