How does the Web Security Service proxies handle DNS requests internally

Products

• Cloud Secure Web Gateway - Cloud SWG

Issue/Introduction

As an administrator, I would like to understand how DNS queries are handled by the Cloud Secure Web Gateway proxy servers.

Environment

Cloud Secure Web Gateway

Any explicit or transparent proxy deployment type.

Resolution

WSS proxy makes DNS queries against domains that connect to the service.

As long as the client (e.g: browser) adds and passes the server name in the SNI header within the client-hello and/or the proxy has information about the domain that it needs to resolve for.

The WSS proxy does this as an additional security measure.