Load Balancer
Load balancing improves the distribution of workloads across multiple computing resources
Two Types
Layer - 4
Uses information defined at the networking transport layer (Layer 4) as the basis for deciding how to distribute client requests across a group of servers.
Act upon data found in network and transport layer protocols
Layer - 7
Distribute requests based upon data found in application layer protocols such as HTTP
Requests are distributed to a particular server based on a configured algorithm.
Some of standard algorithms are
- Round robin
- Weighted round robin
- Least connections
- Least response time
Layer 7 load balancers can further distribute requests based on application specific data such as HTTP headers, cookies, or data within the application message itself, such as the value of a specific parameter.