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Alibaba Cloud SDK:(Not recommended) Request syntax and signature method V2

Last Updated:Jun 02, 2026

Signature method V2 is discontinued. If you construct HTTP requests manually, migrate to the request syntax and signature method V3, which offers stronger security and broader region support.

If you use an Alibaba Cloud SDK, skip this page. The SDK handles request signing automatically and already supports signature method V3.

To migrate, choose the topic that matches the API style of the cloud service you want to access:

Request syntax and signature method V2 for ROA APIs

Request syntax and signature method V2 for RPC APIs

Use these topics only as a reference for understanding the V2 structure. For all new and existing integrations, switch to request syntax and signature method V3.

Note

APIs that support signature method V2 also support signature method V3.