Alibaba Cloud provides two editions of Application Load Balancer (ALB) instances: basic and standard. The features and limits vary by edition. This topic compares the features and limits of basic and standard ALB instances.

Differences

The following table describes the features supported by basic and standard ALB instances.

Feature Basic Standard
Listener protocol
Quick UDP Internet Connections (QUIC) Supported Supported
HTTP/2 Supported Supported
WebSocket Supported Supported
Forwarding rule
Distribute network traffic based on domain names or URLs Supported Supported
Distribute network traffic based on HTTP headers Supported Supported
Distribute network traffic based on query strings Not supported Supported
Distribute network traffic based on cookies Not supported Supported
Distribute network traffic based on HTTP request methods Not supported Supported
Distribute network traffic based on source IP address Not supported Supported
Distribute network traffic based on response status codes Not supported Supported
Distribute network traffic based on response headers Not supported Supported
Redirects Supported Supported
Rewrite requests or return custom responses Not supported Supported
Add or delete headers Not supported Supported
Traffic mirroring Not supported Supported (submit a ticket to be included in the whitelist first)
QPS throttling Not supported Supported (submit a ticket to be included in the whitelist first)
AScript Not supported Supported (submit a ticket to be included in the whitelist first)
Security
Access control based on whitelists and blacklists Supported Supported
TLS cipher suites Supported Supported
Server Name Indication (SNI) for multiple certificates Supported Supported
Rivest-Shamir-Adleman (RSA) and elliptic-curve cryptography (ECC) certificates Supported Supported
ECC certificates Supported Supported
End-to-end data transfer over HTTPS Not supported Supported
Custom TLS cipher suites Not supported Supported
TLS 1.3 Supported Supported
Monitoring
Access logs Supported Supported

Limits

ALB Basic Standard
Instance
The number of additional certificates that can be added to each ALB instance (excluding default certificates) 10 25
The number of forwarding rules that can be configured for each ALB instance (excluding default forwarding rules) 40 100
The number of listeners that can be added to each ALB instance 50 50
The number of backend servers that can be added to each ALB instance 200 1000
Listener
The number of network access control lists (ACLs) that can be associated with each listener 3 3
The number of network ACL entries that can be associated with each listener 300 1000
Region
The number of custom security polices supported in each region 50
The number of health check templates supported in each region 50
The number of ALB instances supported in each region 60
The number of network ACLs supported in each region 1000
The number of server groups supported in each region 3000
Server group
The number of listeners or forwarding rules that can be associated with each server group 50
The number of ALB server groups in which a backend server (IP address) can be specified 200
The number of backend servers (IP addresses and ports) that can be added to each server group 1000
Forwarding rule
The number of actions that can be specified in each forwarding rule 3 5
The number of match conditions that can be specified in each forwarding rule 5 10
The number of wildcards that can be used in each forwarding rule 5 10
Network ACL and security policy
The number of listeners that can be associated with each network ACL 50
The number of entries that can be added to each network ACL 1000
The number of listeners that can be associated with each custom security policy 10