| Feature | Application Load Balancer | Network Load Balancer |
|---|---|---|
| Supported Protocols | HTTP, HTTPs, HTTP/2 | TCP, UDP |
| Supported Target Group Types | Instance, IP, Lambda | Instance, IP |
| Lambda as target group | ✅ Supported | ❌ Not-Supported |
| Performance | Lesser than NLB | 🚀 Low-latency & High throughput (millions of requests per second) |
| Cross-zone Load Balancing | ✅ Enabled by default | ❌ Disabled by default |
| Elastic IP | ❌ Not-Supported, uses Private IP address and exposes fixed DNS record. | ✅ Supported, can expose both DNS and elastic IP. |
| Preserve source IP Address | ❌ Not-Supported | ✅ Supported |
| TLS Offloading/Termination | ✅ Supported | ✅ Supported |
| Advanced Routing | ✅ Supported - Advanced Content-based routing routing based on Source IP address, path, host, HTTP headers, HTTP method, and query string. |
❌ Not-Supported |
| Dynamic Port Mapping | ✅ Supported | ❌ Not-Supported |
| User authentication | ✅ Supported - ALB can authenticate users before they are allowed to pass through the load balancer. - Supports OpenID Connect protocol, SAML, LDAP, Microsoft Active Directory etc. |
❌ Not-Supported |
| Fixed response | ✅ Supported - ALB has the ability to reply directly to the client with a fixed response, such as a custom HTML page. |
❌ Not-Supported |
| WebSockets | ✅ Supported | ❌ Not-Supported |
| Multiple TLS/SSL certificates using Server Name Indicator (SNI) | ✅ Supported | ❌ Not-Supported |
| Exposes | Fixed DNS name (=URL) | Fixed-IP |