Sauce Labs recommends using Sauce Connect Proxy to test internal sites and applications, rather than whitelisting Sauce Labs IP addresses for incoming connections.
You can find further information on this topic at
https://wiki.saucelabs.com/display/DOCS/Why+Sauce+Labs+Recommends+Sauce+Connect+Proxy+Over+Whitelisting+IP+Addresses
If you need to whitelist connections to Sauce Labs so that Sauce Connect Proxy will work correctly, we recommend whitelisting hostnames rather than IP addresses. See the Whitelisting for Restricted Networks section at
https://wiki.saucelabs.com/display/DOCS/System+and+Network+Requirements+for+Sauce+Connect+Proxy
