OpenDNS

OpenDNS is a cloud-delivered Domain Name System (DNS) security and content-filtering service used to enforce internet access policies and block known malicious domains.

• Cloud-based DNS-layer security and threat protection for enterprise and institutional networks.
• Web filtering and policy enforcement for user access to internet domains across locations and devices.
• Protection against phishing, malware, and command-and-control domains using reputation and threat intelligence.
• Centralized management console for configuring DNS policies, reporting, and visibility into DNS queries.
• Integration with broader Cisco cloud security services for unified access and threat defense.

More About OpenDNS

OpenDNS provides DNS-layer security services that organizations use as part of their network and security architecture to control and monitor outbound DNS requests before connections are established. By pointing recursive DNS traffic from endpoints, branch offices, or data centers to OpenDNS resolvers, enterprises can apply security and access policies without deploying inline hardware at every site. This approach is used in environments that include distributed workforces, roaming users, and multi-site networks.

The service operates at the DNS protocol layer and evaluates domain requests against threat intelligence and policy rules. When a user or workload queries a domain, OpenDNS can resolve it, block it, or redirect the request to a block page based on configured policies. This capability is used to reduce exposure to phishing, malware distribution, and command-and-control infrastructure and to enforce acceptable-use policies. Because it works at the DNS layer, it applies regardless of the underlying IP network or physical location, as long as traffic is directed to the service’s resolvers.

From a technology perspective, OpenDNS relies on standard DNS protocols and augments them with security analytics, domain reputation, and policy controls. Organizations commonly integrate the service into existing network topologies by configuring Dynamic Host Configuration Protocol (DHCP) scopes, router settings, or endpoint agents to send DNS queries to the OpenDNS infrastructure. The management interface provides logging and reporting on DNS activity, which security and network teams use for visibility, investigations, and policy tuning.

Within enterprise security portfolios, OpenDNS falls under the DNS-layer security and secure access (network security) category and is often positioned alongside secure web gateways and cloud-delivered security services. Compared with traditional perimeter firewalls or on-premises (on-prem) web filters, it focuses on the domain-resolution step rather than full Hypertext Transfer Protocol (HTTP) inspection, which allows use in bandwidth-constrained or highly distributed environments. It is particularly aligned with use cases where organizations need a control point for internet-bound traffic without backhauling all traffic to a central location.

OpenDNS is part of Cisco’s broader cloud security offerings, integrating with other Cisco security platforms (network security, cloud-delivered security). This positioning allows enterprises already using Cisco networking and security technologies to treat DNS security as one component of a wider access and threat protection architecture. In marketplace and directory taxonomies, OpenDNS is best categorized under DNS security, cloud-delivered network security, and web filtering, with applicability across corporate networks, educational institutions, and public-sector environments that require policy-based internet access control.