Networking 101

A network connects local devices together and allows them to communicate. The Internet connects these networks together and acts as one large network. Your network is connected to the internet through your Internet Service Provider (ISP). Having a robust and well designed network, coupled with a reliable internet connection, allows for uninterrupted communication of all of your devices: both between them, and with connected services such as Square. 

A network is typically composed of:

• A modem. Typically provided by your internet provider. It is responsible for sending and receiving signals from the ISP. Usually connected through the means of Fiber, Cable, DSL (over phone wire), or sometimes cellular. 

• A router, which disperses the signal to devices on the network. In a typical network setup, the modem is connected to the router.

• A network switch is used to connect devices together on a network. The network switch acts as a wired extension point, and connects to the router, or other switches.

• Access points (wireless AP) are network devices that transmits and receives data over a wireless local area network (WLAN), serving as the interconnection point between the WLAN and a fixed wire network. Simply put: they allow your devices (laptops, phones, etc) to connect to your network wirelessly.

In certain cases, one physical piece of equipment might have multiple functions. For example, UniFi Express provides an all-in-one router and wireless access point, but you will still need a network switch to wire in additional devices. Though practical in certain use cases (such as food trucks), using all-in-one devices is not recommended as they make it harder to isolate any network issues.

Other terms you may come across:

• PoE stands for Power over Ethernet and uses an Ethernet cable to provide both power and network connectivity with one cable without the need for an additional power line running through walls and ceilings.

• LAN stands for Local Area Network. A LAN, or local area network, is a group of connected devices within a localized area that usually share a centralized Internet connection. 

• A wireless local-area network (WLAN) is a group of devices that form a network based on radio transmissions rather than wired connections. A Wi-Fi network is a type of WLAN.

• An Internet Protocol address (IP address) is a numerical label such as 192.0.2.1 that is assigned to a device connected to a network that uses the Internet Protocol for communication. IP addresses allow the network to route the correct information to the correct devices.

• A MAC address (media access control address) is a unique identifier assigned to each device connected to the network. MAC addresses are constant values that do not change. In comparison, IP addresses are used to uniquely identify a device's network connection but may change as devices move between WLANs. An IP address alone does not indicate whether a device is connected to a network.

• A domain name is the text that maps to an IP address. Domain names are used every day as the text that a user types into a browser window to reach a particular website. The subdomain is simply a part of a main domain. For example, if a domain offered an online store as part of their website example.com , it might use the subdomain shop.example.com .

• “Cat5e”, “Cat6” is the specification for Ethernet cables that are used for networking which defines their performance. Cat5e is most commonly used.

• “Wi-Fi 5”, “Wi-Fi 6”, “Wi-Fi 6e”, and “Wi-Fi 7” are the version of the protocol supported by your Wi-Fi network/devices. Newer versions typically provide additional features and performance improvements.

• A firewall is a network security system that monitors and controls all network traffic based on security rules. A firewall establishes a barrier between a trusted network and an untrusted network, such as the Internet.

Depending on your network setup and its complexity, you may come across more complex needs. We recommend working with a networking professional for any advanced configuration, such as firewall modifications.

• Network segmentation

  • A VLAN is a virtual local area network. It allows you to group your devices to a different “virtual network” while being physically on the same network. Devices on different VLANs are digitally isolated from each other, as if they were using different physical networks

  • A subnet is a subdivision of your network, using the IP Protocol. Networks can be divided into two or more networks and it is called subnetting. VLANs and subnets are commonly used together, to divide or unify groups of devices to control how information travels on your network. 

  • This is important as Square requires that Point of Sale devices are on the same subnet.

• Network communications

  • UDP and TCP and communication protocols. They define how the information navigates on the network. The main difference between TCP (transmission control protocol) and UDP (user datagram protocol) is that TCP is a connection-based protocol and UDP is connectionless. While TCP is more reliable, it transfers data more slowly. UDP is less reliable but works more quickly.

  • Hypertext Transfer Protocol (HTTP) is a protocol for fetching resources such as HTML documents. It is the foundation of any data exchange on the Web. HTTPS transmits all data in encrypted form. It’s essential for sensitive data, so that no no third parties can intercept the data over the network. HTTPS relies on the Transport Layer Security (TLS) protocol for secure communications over the network. 
    
    Note: “WPA”, “WPA2”, “WEP” are Wi-Fi security standards designed to protect communications via encryption. Using some encryption is always better than using none, but WEP is the least secure of these standards, and you should not use it.