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In modern network environments, providing seamless communication and service discovery for Apple devices is essential. Bonjour, Apple’s zero-configuration networking protocol, is widely used for device discovery, resource sharing, and communication in local area networks (LAN). It allows devices such as printers, cameras, speakers, and computers to automatically detect and connect to each other without requiring users to manually configure IP addresses or services.

Cisco’s Wireless LAN Controller (WLC) is an industry-leading solution for managing wireless networks, and it supports Bonjour to make it easier for Apple devices to discover and interact with services in the network. In this blog post, we’ll walk through the process of configuring Bonjour services on Cisco WLC, covering the key concepts and step-by-step configuration.

What is Cisco WLC?

Cisco Wireless LAN Controller (WLC) is a centralized device used to manage multiple wireless access points (APs) in a network. It provides centralized control over network policies, configuration, monitoring, and security. Cisco WLC simplifies the management of wireless networks by offering centralized management, automatic configuration, and scalability for enterprises.

Bonjour Protocol Overview

Bonjour is a service discovery protocol used primarily by Apple devices. It helps devices discover network services like printers, file sharing, and media streaming, all without requiring manual intervention. Bonjour uses the mDNS (Multicast DNS) protocol to allow devices to resolve hostnames and discover services over a local network.

For example, when an Apple device like an iPhone or a MacBook is connected to the network, it uses Bonjour to automatically detect available services like printers, speakers, and file servers. The device will automatically display these services in the relevant application without needing IP addresses or additional configuration.

In enterprise environments, Bonjour is critical for allowing Apple devices to seamlessly connect to network resources. Cisco WLC can integrate with Bonjour to enable this feature across the wireless network.

Cisco WLC and Bonjour Integration

Cisco’s WLC provides support for Bonjour services through its Bonjour Gateway feature. This feature helps extend Bonjour service discovery across different subnets or VLANs, ensuring that Apple devices can find network services even when they are not on the same subnet.

The WLC acts as a Bonjour gateway to facilitate service discovery across multiple subnets, even though Bonjour typically operates in a local subnet. The key benefit of enabling Bonjour on Cisco WLC is that it simplifies the management of Bonjour services and extends service discovery across VLANs.

Key Benefits of Cisco WLC with Bonjour

1. Multi-VLAN Bonjour Support: With Bonjour Gateway, Cisco WLC can help Bonjour services traverse VLANs or subnets, enabling cross-VLAN service discovery.
   
   
2. Enhanced Apple Device Connectivity: By configuring Bonjour on Cisco WLC, organizations can ensure seamless discovery and access to Apple devices and services.
   
   
3. Simplified Service Discovery: The WLC automatically broadcasts the service advertisements and makes it easier for devices to discover network resources like printers, file shares, and cameras.
   
   
4. Scalable Deployment: Bonjour Gateway on Cisco WLC enables the deployment of Bonjour across large and distributed networks by allowing Bonjour services to be accessed and shared across multiple network segments.

Steps to Configure Cisco WLC for Bonjour

Before diving into the configuration steps, ensure you have the following prerequisites in place:

• Cisco WLC should be running a version that supports Bonjour Gateway. Screen shots below are from version 17.9.4a
  
  
• Your network should have multiple VLANs configured if you plan to use Bonjour across different subnets.
  
  
• The devices (Apple devices or Bonjour-capable printers, etc.) should be connected to the same network and should support Bonjour.

Now, let's look at the configuration steps.

Step 1: Configure Multicast Mode in your C9800 controller

1. Go to Configuration -> Services -> multicast 
   
   
   
   
2. Enable "Global Wireless Multicast Mode"
   
   
   
   
3. Set AP CAPWAP Multicast to "Multicast"
   
   
   
   
4. Assign Multicast IP in "AP CAPWAP IPv4 Multicast group Address" (range 224.0.0.0 to 239.255.255.255). The multicast address for Apple's Bonjour service is 224.0.0.251 for IPv4
   
   
   
   
5. Enable "Wireless mDNS Bridging"
   

1. Enable "IGMP Snooping" on VLANs.
         1.Click on the arrows to move VLANs to the Enable box to the right.
   
   
   
   
2. Save the Configuration: Apply the changes and save configurations.

Step 2: Enable Bonjour

8. Navigate to the Bonjour Configuration Page: Go to Configuration > Wireless > mDNS.
   
   
   
9. Enable Bonjour Gateway: To enable Bonjour across multiple subnets, check the option for Bonjour Gateway.
   
   
   
10. Save the Configuration: Apply the changes and save configurations.

Step 3: Configure Bonjour Gateway for VLAN

1. Navigate to the WLANs: Go to Configuration > Layer2 > VLAN.
   
   
   
2. Navigate to the Advance Tab
   
   
   
3. Enable mDNS Gateway:

Step 4: Configure Bonjour Gateway for WLANs

1. Navigate to the WLANs: Go to Configuration > Tags & Profiles > WLANs.
   
   
   
2. Navigate to the Advance Tab
   
   
3. Assign mDNS Mode to Gateway:
   

Step 5: Verify Bonjour Configuration

After configuring Bonjour on the WLC, it’s essential to verify that everything is working correctly.

1. Test Service Discovery: Use an Apple device (Mac, iPhone, etc.) to check if the configured services (like printers, AirPlay devices, etc.) are automatically discovered. I’ve used Sonos App on an android phone to discover Sonos devices.
   
   
2. Check Logs: Monitor the logs to identify any issues with Bonjour advertisements or service discovery. Go to Monitor > Logs to view Bonjour-related messages.

Step 6: Troubleshooting

If you experience issues, there are several things to check:

• VLAN and IP Connectivity: Ensure that the devices are properly connected to the correct VLANs, and there’s no issue with inter-VLAN routing.
  
  
• Service Type Configuration: Double-check that the correct services are enabled and assigned to the appropriate VLANs.
  
  
• Broadcast Traffic: Ensure that multicast and broadcast traffic required by Bonjour is not being blocked or filtered.

Conclusion

Configuring Cisco WLC with Bonjour allows businesses to offer seamless service discovery for Apple devices, extending Bonjour functionality across multiple VLANs and subnets. This setup is especially valuable in enterprise environments where Apple devices are prevalent and the need for network resource discovery is essential.

By configuring Cisco WLC as a Bonjour gateway and enabling Bonjour services, organizations can provide a rich user experience for Apple users while simplifying the management of network services. As wireless and mobile devices become more ubiquitous, leveraging the full potential of Bonjour with Cisco WLC will ensure your network is ready to support a range of advanced, zero-configuration services.

As always if you have any questions on your network security and would like to schedule a free consultation with us, please reach out to us at sales@lookingpoint.com and we’ll be happy to help!