A load balancer distributes user traffic across multiple instances of your applications. By spreading the load, load balancing reduces the risk that your applications experience performance issues. Google's Cloud Load Balancing is built on reliable, high-performing technologies such as Maglev, Andromeda, Google Front Ends, and Envoy—the same technologies that power Google's own products.
Cloud Load Balancing offers a comprehensive portfolio of application and network load balancers.
Use our global proxy load balancers to distribute millions of requests per second among backends in multiple regions with our Google Front End fleet in over 80 distinct locations worldwide—all with a single, anycast IP address. Implement strong jurisdictional control with our regional proxy load balancers, keeping your backends and proxies in a region of your choice without worrying about TLS/SSL offload. Use our passthrough load balancers to quickly route multiple protocols to backends with the high performance of direct server return (DSR). Cloud Load Balancing overview
Key features
Cloud Load Balancing offers the following load balancer features:
Single anycast IP address. With Cloud Load Balancing, a single anycast IP address is the frontend for all of your backend instances in regions around the world. It provides cross-region load balancing, including automatic multi-region failover, which moves traffic to failover backends if your primary backends become unhealthy. Cloud Load Balancing reacts instantaneously to changes in users, traffic, network, backend health, and other related conditions. Seamless autoscaling. Cloud Load Balancing can scale as your users and traffic grow, including easily handling huge, unexpected, and instantaneous spikes by diverting traffic to other regions in the world that can take traffic. Autoscaling does not require pre-warming: you can scale from zero to full traffic in a matter of seconds. Software-defined load balancing. Cloud Load Balancing is a fully distributed, software-defined, managed service for all your traffic. It is not an instance-based or device-based solution, so you won't be locked into a physical load-balancing infrastructure or face the high availability, scale, and management challenges inherent in instance-based load balancers. Layer 4 and Layer 7 load balancing. Use Layer 4-based load balancing to direct traffic based on data from network and transport layer protocols such as . Use Layer 7-based load balancing to add request routing decisions based on attributes, such as the HTTP header and the uniform resource identifier. External and internal load balancing. Defines whether the load balancer can be used for external or internal access. An external load balancer accepts traffic from the internet, whereas an internal load balancer only accepts RFC 1918 traffic. You can use external load balancing when your users reach your applications from the internet. You can use internal load balancing when your clients are inside of Google Cloud. To learn more, see . Global and regional load balancing. Defines the scope of the load balancer. A global load balancer supports backends in multiple regions, whereas a regional load balancer supports backends in a single region. Even though the IP address of a regional load balancer is located in one region, a regional load balancer is globally accessible. You can distribute your backends in single or multiple regions to terminate connections close to your users and to meet your high availability requirements. To learn more, see . Routing of traffic in Premium Tier and Standard Tier. The load balancing services in Google Cloud come in different flavours depending on the network tier you choose, that is, Premium Tier or Standard Tier, with the former being more expensive than the latter. The Premium Tier leverages Google's high-quality global backbone whereas the Standard Tier uses the public internet to route traffic across the network. The network tier you choose depends on whether you prioritize cost or performance for your enterprise workload. Some load balancing services are only available in Premium Tier and not the Standard Tier. To learn more, see . Advanced feature support. Cloud Load Balancing supports features such as IPv6 load balancing, , , WebSockets, user-defined request headers, and protocol forwarding for private virtual IP addresses (VIPs). It also includes the following integrations: Integration with for cached content delivery. Cloud CDN is supported with the global external Application Load Balancer and the classic Application Load Balancer. Integration with to protect your infrastructure from distributed denial-of-service (DDoS) attacks and other targeted application attacks. Always-on DDoS protection is available for the global external Application Load Balancer, the classic Application Load Balancer, the external proxy Network Load Balancer, and the external passthrough Network Load Balancer. Additionally, Google Cloud Armor supports advanced network DDoS protection only for external passthrough Network Load Balancers. For more information, see .
Types
Cloud Load Balancing offers two types of load balancers: Application Load Balancers and Network Load Balancers. You'd choose an Application Load Balancer when you need a Layer 7 load balancer for your applications with HTTP(S) traffic. You'd choose a Network Load Balancer when you need a Layer 4 load balancer that supports TLS offloading (with a proxy load balancer) or you need support for IP protocols such as UDP, ESP, and ICMP (with a passthrough load balancer).
The following table provides a high-level overview of the different types of Google Cloud load balancers categorized by the OSI layer on which they operate and whether they are used for external or internal access
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Cloud Load Balancing
