Have you ever wondered how your TV shows up on your home network? or how you can cast a video from your phone onto your TV?
The answer to these questions involves networking protocols that are very popular but at the same time not well known to most people.
Home Networking Protocols and Internet Services
Just having computers connected together by WI-FI or Ethernet is the first step. To exchange information they require to have, and use several networking services and protocols.
The Base Layer TCP/IP
Without going into the nitty gritty of networking protocols and the 7 layer model it is helpful to have a basic idea of how these various protocols fit together.
A useful analogy might be a language like English. You can say English is the base layer and you must know English to do any Job in an English speaking country.
However just knowing English isn’t enough to work as a doctor or a lawyer for example as these profession and many others come with a vocabulary and procedures specific to that function.
The same is true of networking were TCP/IP is our English but TCP/IP isn’t enough to read a web page, to do that we need an additional protocol, which uses TCP/IP, and that is HTTP.
So to simplify to do a particular function we need a protocol.
To read web pages we need HTTP, to get and IP address of a website we need DNS to get an IP address we need DHCP. and all of these need TCP/IP.
The main networking ptotocols on home networks are:
IP protocol
All modern networks use the IP networking protocol, and to work on a network all devices require an IP address.
There are two versions of the IP protocol currently in operation.
IPv4 is the original version and is deployed in all home and office networks and on the Internet.
IPv6 is being rolled out and many new networks and network devices support it, but it isn’t used as the default protocol.
DHCP (Dynamic Host configuration Protocol)
DHCP is a service and protocol that requests and assigns IP addresses to computers automatically.
All modern computers,tablets and smart phones are capable of using DHCP and are configured to use it by default.
For home and small office networks the DHCP service is built into the router that connects to the Internet.
For larger office networks this service is configured on a network server.
If no DHCP service is available clients will automatically assign their own IP address (known as a local address) or you can manually assign them( called static addresses).
See understanding DHCP on Home Networks
DNS (domain Name Service)
The domain name system is the heart of the Internet. It is responsible for resolving domain names to IP addresses.
Without DNS you would have to remember the IP address of each website that you visited.
All networking clients (PCs,tablets,Phones) function as DNS clients and have the necessary software built in so that they can use DNS.
The DNS servers store the data and are mainly located on the Internet e.g. your ISP (internet service provider,Google etc).
Large companies will use their own DNS servers locally.
To use DNS the client will need to know the address of a DNS server. This is normally assigned by the DHCP server.
See Understanding DNS and Adding a DNS server to your home network.
MDNS (multicast DNS)– Local version of DNS and is used for locating devices on a local (home) network.-Multicast DNS (MDNS) on Home Networks
MQTT (Message Queue Telemetry transport) -Used for IOT data transfer and home automation. See Smart Homes and MQTT
SSDP (Simple Service Discovery Protocol) – Used in home networks to advertise and discover network services as part of the Universal Plug-and-Play (UPnP) architecture. Wiki -Very good introduction to SSDP
UPnP (Universal Plug and Play) is a service that allows devices on the same local network to discover each other and automatically connect to each other. Used to automatically open ports on home routers.-Wiki
IGMP snooping is the process of listening to Internet Group Management Protocol (IGMP) network traffic to control delivery of IP multicasts. Although it isn’t a protocol it is an important process that you should be aware of. Wiki
Google Cast is a proprietary protocol developed by Google for playing Internet-streamed audiovisual content on a compatible consumer device. Wiki
ARP (Address resolution Protocol)-Used on IPv4 networks to get the MAC address of a destination machine with a given IP address.
Related Tutorials and Resources:
- Using The Ping Command – Home Networking Testing
- 10 Useful Windows Networking Commands
- How to Set Up a Home Network- Beginners Guide
- Home networking course