Non-intrusive traffic management is a core function of Istio. With traffic management, you only need to focus on your own service logic rather than service access management. Traffic management enables you to:

Dynamically modify load balancing policies for cross-service access, such as configuring consistent hashing to forward traffic to specific service pods.
Distribute a certain proportion of traffic to a specific version of a service when the service has two online versions.
Protect services, for example, limiting the number of concurrent connections and requests, and isolating faulty service pods.
Dynamically modify the content of a service or simulate a service running fault.

ASM provides retry, timeout, connection pool, outlier detection, load balancing, HTTP header, and fault injection functions to meet traffic management requirements in most service scenarios.

**Table 1** Common mesh functions and management roles
Mesh Function	Management Role
Mesh Function	Service Initiator	Service Provider
Route management	Y	N
Load balancing	Y	N
Tracing analysis	Y	Y
Service authentication	Y	Y
Observability data	Y	Y
Retry	Y	N
Rewrite	Y	N
Redirection	Y	N
Authorization	N	Y
Fault injection	Y	N
Timeout	Y	N
Connection pool	Y	N
Outlier detection	Y	N
HTTP header	Y	N

Constraints

Traffic management cannot be performed for the service whose configuration diagnosis fails. For details about rectifying faults, see Manual Fixing Items or Auto Fixing Items.

Overview

Constraints