NSX-T REST API has defined limits to control the rate of incoming API requests described as "per-client" connections. For more information regarding the limits, see NSX-T Data Center REST API
VMware NSX
"Per-client" API connections are defined as any API request that authenticates as user "X". If user "X" opens several API connections, the limit is calculated on the total number of requests received on all connections. In the case where the API request has no username, the client is identified by the source IP address.