- #CISCO 2950 SWITCH CONFIGURE VLAN HOW TO#
- #CISCO 2950 SWITCH CONFIGURE VLAN PC#
- #CISCO 2950 SWITCH CONFIGURE VLAN SERIES#
Note: Use the Command Lookup Tool ( registered customers only) to obtain more information on the commands used in this section. CDP is proprietary to Cisco Systems and other manufacturers’ phones may not be able to use this method to configure the IP phone to match the switch’s port configuration. CDP is the mechanism used between the switch and Cisco IP phone in order to configure the Cisco IP phone for communication with the switch port. By default, the CDP is enabled globally on the switch interfaces. You must enable the CDP on the switch port to which the IP phone is connected. The phone should not change (trust) the priority of frames arriving on the phone port from PC.
#CISCO 2950 SWITCH CONFIGURE VLAN PC#
Packets generated by the PC use an assigned CoS value in the 802.1q header.
#CISCO 2950 SWITCH CONFIGURE VLAN HOW TO#
By issuing this command, the switch will instruct the phone on how to process the data packets from the device attached to the access port on the Cisco IP phone. Use the switchport priority extend trust command in order to extend the trust state to the device (PC) connected to the IP phone. The Cisco IP phone can also send untagged voice traffic or it can use its own configuration to send voice traffic to the access VLAN of the switch.
Use the switchport voice vlan V_VLAN_ID command in order to configure a specified voice VLAN, so the IP phone can send voice traffic in IEEE 802.1Q frames with a Layer 2 CoS value. Use the switchport voice vlan dot1p command in order to instruct the switch port to use the IEEE 802.1p priority tagging to forward all voice traffic with a higher priority through the native (access) VLAN. In order to accept tagged frames on a switch port, one of these commands should be configured on the port:
Before you enable voice VLAN, enable the QoS on the switch by issuing the mls qos global configuration command and configure the port's trust state to trust by issuing the mls qos trust cos interface configuration command.īy default, a switch port drops any tagged frames in hardware. When you enable the voice VLAN on the port, all untagged traffic is sent according to default CoS priority. In the switch, the voice VLAN feature is disabled by default. In this section, you are presented with the information to configure the voice VLAN features described in this document. In untrusted mode, the access port on the IP phone receives all traffic in IEEE 802.1Q frames which contain a configured Layer 2 CoS value. In trusted mode, the access port on the IP phone passes the traffic from the PC without any change. You can configure the switch ports which send CDP packets that instruct the attached IP phone to configure the mode (trusted or untrusted mode) for the access port on the phone. The switch can process data traffic which comes from the device attached to the access port on the IP phone. In the access VLAN, untagged (no Layer 2 CoS priority value) In the access VLAN tagged with a Layer 2 CoS priority value In the voice VLAN tagged with a Layer 2 CoS priority value You can configure access ports on the switch to send Cisco Discovery Protocol (CDP) packets in order to instruct an attached IP phone to send voice traffic to the switch by any of these methods: You can configure the switch port, which is connected with an IP phone, to use one VLAN for voice traffic and another VLAN for data traffic from a device attached to the access port of the IP phone. You can configure the Cisco IP phone to forward traffic with an IEEE 802.1p priority, and configure the switch to trust or override the traffic priority assigned by an IP phone. Based on IEEE 802.1p CoS, the switch supports quality of service (QoS) which uses classification and scheduling to send network traffic from the switch. The voice VLAN feature permits the switch ports to carry voice traffic with Layer 3 IP precedence and Layer 2 class of service (CoS) values from an IP phone. Refer to the Cisco Technical Tips Conventions for more information on document conventions. If your network is live, make sure that you understand the potential impact of any command. All of the devices used in this document started with a cleared (default) configuration. The information in this document was created from the devices in a specific lab environment. The information in this document is based on the Cisco Catalyst 2950 Switch. Have a basic understanding of voice VLAN.
#CISCO 2950 SWITCH CONFIGURE VLAN SERIES#
Have a basic knowledge of configuration on Cisco Catalyst 2960/2950 Series Switches. Make sure that you meet these requirements before you attempt this configuration: Specifically, this document shows how to configure the voice VLAN feature on a Cisco Catalyst 2950 Switch. This document provides a sample configuration for voice VLAN on Cisco Catalyst 2960/2950 Series Switches.