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Capita Education Software Solutions is a trading name of Capita Business Services Ltd. Our Registered office is 30 Berners Street, London, W1T 3LR and our registered number is 02299747. Further information about Capita plc can be found in our legal statement.

SIMS 8 - APIs - V3 - Throttling Policy

In order to protect our systems from denial of service attacks and ensure performance of our systems for all of our customers, our V3 APIs (similar to V1/V2) for SIMS Primary are protected by Microsoft Azure API Manager.


We have set a default throttle of 5 calls per second per technical integrator initially and will review this as and when we obtain feedback from technical integrators and/our our service technicians. If this or future rate limits are exceeded an error code 429 will be returned, for example:

ERROR: 429: { "statusCode": 429, "message": "Rate limit is exceeded. Try again in x seconds." }

It is essential that any web based application which makes API calls is coded to expect failure.  Retry policies for error 429 and various similar errors should consider an exponential delay-retry timings for example:

   First Fail:   Wait 2 seconds

   Second Fail: Wait 4 seconds

   ...        Doubling utill say the wait period is 1h 

After an hour there is either a long-planned outage in progress or something more fundamentally wrong.  Contact Partner.Support@Capita.co.uk for assistance.