Chapter 18

What is a communication channel? What is its connection to asynchronous programming?

Communication channels are used to denote both the physical wiring connection between different systems and the logical communication of data that facilitates computer networks. The latter is related to computing, and is more relevant to the idea of asynchronous programming. Asynchronous programming can provide functionalities that complement the process of facilitating communication channels efficiently.

What are the two main parts of the Open Systems Interconnection (OSI) model protocol layers? What purposes do each of them serve?

The media layers contain fairly low-level operations that interact with the underlying process of the communication channel, while the host layers deals with high-level data communication and manipulation.

What is the transport layer? Why is it crucial to communication channels?

The transport layer is often viewed as the conceptual transition between the media layers and the host layers, responsible for sending data along end-to-end connections between different systems.

How does asyncio facilitate the implementation of server-side communication channels?

Server-wise, the asyncio module combines the abstraction of transport with the implementation of an asynchronous program. Specifically, via its BaseTransport and BaseProtocol classes, asyncio provides different ways to customize the underlying architecture of a communication channel.

How doesasynciofacilitate the implementation of client-side communication channels?

Together with the aiohttp module and, specifically, aiohttp.ClientSession, asyncio also offers efficiency and flexibility regarding client-side communication processes, via asynchronously making requests and reading the returned responses.

What isaiofiles?

The aiofiles module, which can work in conjunction with asyncio and aiohttp, helps to facilitate asynchronous file reading/writing.