Load balancing Options

Azure Load balancing Service categorization

Azure Load Balancing services are categorized in below categories:

Global versus Regional: 

Global : It distributes the traffic across regional backends, clouds or hybrid on-premises services. These Services route end user traffic to the closest available backend. 

Regional: It distributes traffic within virtual networks across Vms or Zonal-redundant service endpoints within a region. 

HTTP(S) versus non-HTTP(S)

HTTP(S) : These services are Layer 7  load balancers that accept HTTP(S) traffic. They are mostly used for web applications or other HTTP(S) endpoints. They include features such as SSL offload , Web Application firewall , path-based load balancing and session affinity. 

Non-HTTP(S) : Load Balancing services can handle non-HTTP(S) traffic and are recommended for non-web workloads. 

Below table summarizes these categories.

Azure load balancing Services: 

Below are some main Load Balancing services currently available in Azure

Front Door: It is the Application delivery network that provides Global Load balancing and Site Acceleration Service for Web Applications. 

It offers layer 7 capabilities for your applications like SSL offload , path based Routing , fast Failover caching , , in order to improve the performance and high-availability. 

Enterprise can use the front door to provide higher Availability for applications than deploying in a single region. If regional outage affects primary region, Front Door will fail over to Secondary regions. 

Traffic Manager: It is the DNS based traffic load balancer that enables you to distribute traffic optimally to service across global Azure Regions. As it is a DNS based load-balancing service , it load balances only at the domain level , due to which it cannot fail over as quickly as Front door due to common challenges around DNS caching and system not honoring DNS TTLs. 

Application Gateway: It provides Application gateway controller (ADC) as a Service. It offers various Layer 7 load-balancing capabilities , which can be used to optimize web farm productivity by offloading CPU-intensive SSL termination to gateway. 

Azure Load balancer: it is a high performance , ultra low-latency layer 4 load balancing service for all UDP and TCP protocols. It handles millions of requests per second while ensuring High-Availability. 

It is a Zone redundant , ensuring high availability , across different Availability Zones.