# Web browsers

<table><thead><tr><th width="156">Source</th><th width="139">Destination</th><th width="114">Protocol</th><th width="103">Port</th><th>Description</th></tr></thead><tbody><tr><td>Web browser (HTML5) and Let's Encrypt service</td><td>RAS Web Admin Service [RAS Management Portal]</td><td>TCP</td><td>20443</td><td>Admin access to HTML5 based Management Portal of RAS environment</td></tr><tr><td></td><td>HALB</td><td>TCP</td><td>80, 443</td><td><p>End-user access to Parallels RAS Web Client (on Secure Gateway in Normal mode) through the HALB</p><p></p><p><strong>Note:</strong> Ports 80 and 443 must be open for incoming requests when using Let's Encrypt.</p></td></tr><tr><td></td><td>RAS Secure Gateway</td><td>TCP</td><td>80, 443</td><td><p>End-user access to Parallels RAS Web Client (on Secure Gateway in Normal mode)</p><p><strong>Note:</strong> Ports 80 and 443 must be open for incoming requests when using Let's Encrypt.</p></td></tr></tbody></table>


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# Agent Instructions: Querying This Documentation

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
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```

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Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.