Single service comparison

Azure API Management combines a tenant-level control plane, policy execution engine, developer portal, and gateway tiers in one product; Huawei APIG (API Gateway) is the closest equivalent for hosting, securing, and governing API traffic, but its developer-portal, monetization, and subscription-management surface is narrower. APIG splits gateway deployment into shared and dedicated instances with selectable specifications up to roughly 80,000 TPS per gateway, whereas APIM vehicles scale through named SKUs (Consumption serverless, Standard, Premium with multi-region unit capacity). Verify APIG environment, group, throttling, and SLA tiers against each APIM SKU before assuming parity, especially for Premium-only features like multi-region deployment and self-hosted gateways.

Policy and request-transformation semantics differ materially. APIM exposes an XML policy document with inbound/outbound/backend sections supporting set-variable, rewrite-uri, send-request, validate-jwt, rate-limit-by-key, and cache policies; APIG uses plugin-style policies configured in the console or OpenAPI extensions for traffic control, CORS, response-shaping, signature, and custom authorizers via FunctionGraph. There is no automatic policy XML-to-APIG converter, so each policy must be rewritten and tested. APIG integrates with IAM for auth, WAF for web attack protection, and CCE/Nacos for microservice discovery, but APIM's native integration set (App Service, Functions, Event Grid, Application Insights, Azure Monitor) does not map one-to-one; expect to rewire observability to AOM/LTS and identity to IAM or APIG custom authorizers.

Operating responsibility and integration scope diverge. APIM is a single converged service for gateway, portal, and analytics; on Huawei Cloud, API-only exposure is covered by APIG, but broader application, message, data, and device integration is the domain of ROMA Connect, a separate iPaaS with 100+ connectors. Architecturally, pure API gateway workloads land on APIG, while integration-heavy APIM use cases that leveraged APIM's backend orchestration or third-party system connectivity may need APIG plus ROMA Connect rather than APIG alone. Do not treat APIG and ROMA Connect as interchangeable; they serve distinct workload variants and are billed and operated separately.

Assess the APIM inventory first: list APIs, OpenAPI/SOAP definitions, named-value secrets, policies, subscriptions, products, tags, and the gateway tier in use (Consumption, Standard, or Premium multi-region). For each, decide the target: pure external-facing API traffic maps to APIG; flows that orchestrate third-party SaaS, legacy systems, or messaging map to ROMA Connect, possibly fronted by APIG. Confirm APIG instance type (shared or dedicated), region availability, and per-gateway TPS against your peak and multi-region requirements, because not every APIM Premium capability has a direct APIG equivalent.

Migrate configuration manually since no automated APIM-to-APIG importer exists. Export OpenAPI/SWAGGER specs from APIM and import them into APIG, then recreate backend routing, app quotas, throttling (per app, API, user, IP), CORS, and authentication (IAM, custom authorizers via FunctionGraph, or third-party auth). Re-implement policies: validate-jwt becomes APIG custom-authorizer logic, rate-limit-by-key maps to APIG request throttling, set-variable/rewrite-uri require plugin configuration, and caching must be rebuilt using APIG cache or a front CDN. Recreate named values in APIG or KMS, regenerate subscription keys, and stand up a developer-facing announcement rather than assuming APIM's developer portal moves over.

Validate control and data plane behavior before cutover. Replay representative request payloads against the APIG endpoint to compare latency, status codes, headers, and transformation output with the APIM baseline. Verify throttling thresholds, backend circuit breaking, mTLS or WAF integration, and Observation via AOM/LTS versus Application Insights. Run a parallel or shadow phase: point a test host or weighted traffic split at APIG while APIM remains authoritative, then promote APIG as primary once error rates and policy-equivalence tests are acceptable. Preserve the APIM instance in a read-only state during rollback window.

Mind the gaps and cost-model shift. APIM is billed per gateway unit and request volume by tier; APIG is billed by instance specification and request volume, with add-on charges for WAF, FunctionGraph custom authorizers, AOM, and CDN when used. Recalculate TCO using peak TPS, monthly request count, retention, and cross-region traffic, because dedicated APIG instances can cost more than a serverless APIM Consumption tier at low volume and less than Premium at high volume. Document unsupported features (self-hosted gateway, multi-region units, APIM developer portal customization equivalents) and either retain APIM as an edge, engineer an alternative with APIG plus CCE/Nginx, or accept the capability reduction explicitly.