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Check out the MS switches’ CDP support for voice VLANs

Easily configure Cisco VoIP phones to use separate VLANs for voice and data.

Many organizations use voice over IP (VoIP) to drive down telephony infrastructure costs and to provide more dynamic multimedia experiences for end users. VoIP traffic is time-sensitive and often corralled in its own virtual LAN (VLAN) to isolate it from regular data traffic.

It’s easy to steer voice traffic to a separate voice VLAN using Cisco Meraki MS switches — even for organizations using Cisco VoIP phones that only support the Cisco Discovery Protocol (CDP).

Simply navigate in the Cisco Meraki dashboard to the switch port connected to the IP phone, and specify the desired voice VLAN. You can also specify a separate data VLAN for any IP devices connected directly to the phone itself, splitting voice and data traffic (check out our VoIP deployment solution guide for step-by-step instructions).

MS switches now use CDP to advertise the appropriate voice and data VLANs to any directly connected Cisco IP phones. To illustrate this functionality, you can run a packet capture on an individual switch port from within the dashboard (exporting the capture to CloudShark); here are example results:

This MS switch is advertising voice VLAN 200 to a connected CDP-enabled IP phone.


Meraki MS switches also support LLDP, so it’s possible to specify a voice VLAN for IP phones that do not use CDP — the configuration is the same, in fact. So regardless of which vendor an organization chooses for its IP phones, Meraki MS switches allow for distinct VLANs for voice and data to be configured for ports connected to those phones.

Meraki switches offer additional features to optimize VoIP traffic and facilitate deployment of IP phones, including PoE models supporting PoE/PoE+ across all ports and QoS (using DSCP) to prioritize voice traffic. For more details, check out our blog post here.