A load balancer distributes traffic evenly among each system in a pool. A load balancer can help you achieve both high availability and resiliency.
Say you start by adding additional VMs, each configured identically, to each tier. The idea is to have additional systems ready, in case one goes down, or is serving too many users at the same time.
Azure Load Balancer is a load balancer service that Microsoft provides that helps take care of the maintenance for you. Load Balancer supports inbound and outbound scenarios, provides low latency and high throughput, and scales up to millions of flows for all Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) applications. You can use Load Balancer with incoming internet traffic, internal traffic across Azure services, port forwarding for specific traffic, or outbound connectivity for VMs in your virtual network.
When you manually configure typical load balancer software on a virtual machine, there’s a downside: you now have an additional system that you need to maintain. If your load balancer goes down or needs routine maintenance, you’re back to your original problem.
Azure Application Gateway
If all your traffic is HTTP, a potentially better option is to use Azure Application Gateway. Application Gateway is a load balancer designed for web applications. It uses Azure Load Balancer at the transport level (TCP) and applies sophisticated URL-based routing rules to support several advanced scenarios.
- Cookie affinity. Useful when you want to keep a user session on the same backend server.
- SSL termination. Application Gateway can manage your SSL certificates and pass unencrypted traffic to the backend servers to avoid encryption/decryption overhead. It also supports full end-to-end encryption for applications that require that.
- Web application firewall. Application gateway supports a sophisticated firewall (WAF) with detailed monitoring and logging to detect malicious attacks against your network infrastructure.
- URL rule-based routes. Application Gateway allows you to route traffic based on URL patterns, source IP address and port to destination IP address and port. This is helpful when setting up a content delivery network.
- Rewrite HTTP headers. You can add or remove information from the inbound and outbound HTTP headers of each request to enable important security scenarios, or scrub sensitive information such as server names.
What is a Content Delivery Network (CDN)?
A content delivery network (CDN) is a distributed network of servers that can efficiently deliver web content to users. It is a way to get content to users in their local region to minimize latency. CDN can be hosted in Azure or any other location. You can cache content at strategically placed physical nodes across the world and provide better performance to end users. Typical usage scenarios include web applications containing multimedia content, a product launch event in a particular region, or any event where you expect a high-bandwidth requirement in a region.
DNS, or Domain Name System, is a way to map user-friendly names to their IP addresses. You can think of DNS as the phonebook of the internet.
How can you make your site, which is located in the United States, load faster for users located in Europe or Asia?
network latency in azure
Latency refers to the time it takes for data to travel over the network. Latency is typically measured in milliseconds.
Compare latency to bandwidth. Bandwidth refers to the amount of data that can fit on the connection. Latency refers to the time it takes for that data to reach its destination.
One way to reduce latency is to provide exact copies of your service in more than one region, or Use Traffic Manager to route users to the closest endpoint, One answer is Azure Traffic Manager. Traffic Manager uses the DNS server that’s closest to the user to direct user traffic to a globally distributed endpoint, Traffic Manager doesn’t see the traffic that’s passed between the client and server. Rather, it directs the client web browser to a preferred endpoint. Traffic Manager can route traffic in a few different ways, such as to the endpoint with the lowest latency.