About Cisco DNA Service for Bonjour Solution
The Apple Bonjour protocol is a zero-configuration solution that simplifies network configuration and enables communication between connected devices, services, and applications. Using Bonjour, you can discover and use shared services with minimal intervention and configuration. Bonjour is designed for single Layer 2 domains that are ideal for small, flat, single-domain setups, such as home networks. The Cisco DNA Service for Bonjour solution eliminates the single Layer 2 domain constraint and expands the scope to enterprise-grade traditional wired and wireless networks, including overlay networks such as Cisco Software-Defined Access (SD-Access) and industry-standard BGP EVPN with VXLAN. The Cisco Catalyst 9000 series LAN switches and wireless LAN controllers follow the industry standard, RFC 6762-based multicast DNS (mDNS) specification to support interoperability with various compatible wired and wireless consumer products in enterprise networks.
The Cisco Wide Area Bonjour application is a software-defined, controller-based solution that enables devices to advertise and discover Bonjour services across Layer 2 domains, making these services applicable to a wide variety of wired and wireless enterprise networks. The Cisco Wide Area Bonjour application also addresses problems relating to security, policy enforcement, and services administration on a large scale. The new distributed architecture is designed to eliminate mDNS flood boundaries and transition to unicast-based service routing, providing policy enforcement points and enabling the management of Bonjour services. With the Cisco Wide Area Bonjour application, you can seamlessly introduce new services into the existing enterprise environment without modifying the existing network design or configuration.
The enhanced intuitive GUI provides you with centralized access control and monitoring capabilities, combined with the scalability and performance required for large-scale Bonjour services deployments for various supporting enterprise network types.
The following figure illustrates how the Cisco Wide Area Bonjour application operates across two integrated domain networks with end-to-end unicast-based service routing.
Local-Area Service Discovery Gateway Domain - Multicast DNS Mode: The classic Layer 2 multicast flood-n-learn-based deployment model. The service provider and receiver can discover and browse within the common VLAN or broadcast domain without any security and location-based policy enforcement. The Cisco Catalyst switches at the Layer 3 boundary function as the Service Discovery Gateway (SDG) to discover and distribute services between local wired or wireless VLANs based on applied policies. The inter-VLAN service routing at a single gateway is known as Local Area Bonjour.
Local Area Service Discovery Gateway Domain - Unicast Mode: The new enhanced Layer 2 unicast policy-based deployment model. The new mDNS service discovery and distribution using Layer 2 unicast address enables flood-free LAN and wireless networks. Cisco Catalyst switches and Cisco Catalyst 9800 series wireless LAN controllers in Layer 2 mode introduce a new service-peer role, replacing classic flood-n-learn, for new unicast-based service routing support in the network. The service-peer switch and wireless LAN controller also replace mDNS flood-n-learn with unicast-based communication with any RFC 6762 mDNS-compatible wired and wireless endpoints.
Wide-Area Service Discovery Gateway Domain: The Wide Area Bonjour domain is a controller-based solution. The Bonjour gateway role and responsibilities of Cisco Catalyst switches are extended from a single SDG switch to an SDG agent, enabling Wide Area Bonjour service routing beyond a single IP gateway. The network-wide distributed SDG agent devices establish a lightweight, stateful, and reliable communication channel with a centralized Cisco DNA Center controller running the Cisco Wide Area Bonjour application. Service routing between the SDG agents and the controller operates over regular IP networks using TCP port 9991. The SDG agents route locally discovered services based on the export policy.