Load Balancers Glossary

DigitalOcean fully manages Regional Load Balancers and Global Load Balancers, ensuring they are highly available load balancing services. Load balancers distribute traffic to groups of Droplets in specific regions or across different regions, which prevents the health of a backend service from depending on the health of a single server or a single region.

This glossary defines the core concepts behind load balancers to help build your mental model of how load balancers work and understand what the documentation is referring to when it uses certain terminology.

Autobahn|Testsuite is a fully-automated test suite that verifies client and server implementations of the WebSocket Protocol.
In load balancing, a backend pool is a group of resources, such as Droplets, whose traffic are managed by the load balancer.
Classless Inter-Domain Routing notation, or CIDR notation, is a method of representing an IP address network range.
A handshake is the authentication process between two networked devices to ensure that both devices are who they claim to be.
A health check is a scheduled HTTP or TCP request that you can configure to run on a repeating basis to ensure that a service is healthy.
High Availability (HA) is an approach to infrastructure design focusing on reducing downtime and eliminating single points of failure.
The Internet Protocol (IP) is a communications protocol used to connect computers across a network, specifically the internet. IP consists of rules and regulations for transmission of packets across a network including routing and addressing. IP ensures that the packets of data that travel across a network arrive at the correct location.
Keep-Alive, or keepalive, is a signal sent from one device to another in order to maintain the connection between the two devices.
A load balancer distributes traffic across a backend pool of servers to improve the stability and responsiveness of an application.
A port is a communication endpoint of a network connection. A port is identified using a port number for each transport protocol.
A proxy is a computer or software system that acts as a dedicated intermediary between an endpoint device and another server.
SSH (Secure Shell Protocol) is a method to secure remote logins and communications from one computer to another which provides strong authentication and protects communication through strong encryption.
SSL certificate is a digital document outlining the identity of the website.
SSL passthrough is the process of passing SSL-encrypted traffic on to a backend server for decryption.
SSL termination is the process of decrypting traffic encrypted with SSL.
Sticky session, or session persistence occurs when the load balancer creates a connection between a network and a user for a direction of the session.
Tags are keywords associated with DigitalOcean resources. You can use tags to organize and manage resources.
The Transmission Control Protocol (TCP) is a communication standard for programs and computing devices to exchange messages over a network.
Transport Layer Security (TLS) is a security protocol focused on privacy and data security for communication across the internet.
User Datagram Protocol, or UDP, is an established low-latency connection communication protocol between applications.