Answer
This is typically a firewall/IP-whitelisting issue, not a request or authentication problem — a web-based tool like Boomi's or Postman's own web app sends its requests from that vendor's own cloud infrastructure IP ranges, not from the customer's own network, so it isn't covered by whatever IP whitelisting already lets the customer's own internal network (and therefore their locally-installed desktop client) reach IFS Cloud. Getting the network team to whitelist Boomi's and/or Postman's published IP ranges (both vendors publish the specific ranges/hostnames their platforms use) resolves connectivity from the web-based versions of these tools.