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Cisco Umbrella is a cloud-delivered security service that protects users from malicious domains and IPs, regardless of their location or network. When users are off the corporate network, they can use the Cisco Umbrella roaming client, which is embedded in the Cisco AnyConnect client, to enforce Umbrella DNS servers for all DNS queries. This way, Umbrella can block requests to malicious or unwanted domains before a connection is ever made, and provide visibility and protection for users anywhere they go. The Umbrella roaming client does not require any additional agents or end user action, and it can work with or without a VPN connection. References := Cisco Umbrella Roaming, Umbrella Roaming Client - How it Works on Your Company Network