この製品のマニュアルセットは、偏向のない言語を使用するように配慮されています。このマニュアルセットでの偏向のない言語とは、年齢、障害、性別、人種的アイデンティティ、民族的アイデンティティ、性的指向、社会経済的地位、およびインターセクショナリティに基づく差別を意味しない言語として定義されています。製品ソフトウェアのユーザーインターフェイスにハードコードされている言語、RFP のドキュメントに基づいて使用されている言語、または参照されているサードパーティ製品で使用されている言語によりドキュメントに例外が存在する場合があります。シスコのインクルーシブランゲージに対する取り組みの詳細は、こちらをご覧ください。
このドキュメントは、米国シスコ発行ドキュメントの参考和訳です。リンク情報につきましては、日本語版掲載時点で、英語版にアップデートがあり、リンク先のページが移動/変更されている場合がありますことをご了承ください。あくまでも参考和訳となりますので、正式な内容については米国サイトのドキュメントを参照ください。
目次
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
The following are the prerequisites for voice VLANs:
Voice VLAN configuration is only supported on switch access ports; voice VLAN configuration is not supported on trunk ports.
(注) |
Trunk ports can carry any number of voice VLANs, similar to regular VLANs. The configuration of voice VLANs is not supported on trunk ports. |
Before you enable voice VLAN, we recommend that you enable QoS on the switch by entering the mls qos global configuration command and configure the port trust state to trust by entering the mls qos trust cos interface configuration command. If you use the auto-QoS feature, these settings are automatically configured.
You must enable CDP on the switch port connected to the Cisco IP Phone to send the configuration to the phone. (CDP is globally enabled by default on all switch interfaces.)
The following are the restrictions for voice VLANs:
The voice VLAN feature enables access ports to carry IP voice traffic from an IP phone. When the switch is connected to a Cisco 7960 IP Phone, the phone sends voice traffic with Layer 3 IP precedence and Layer 2 class of service (CoS) values, which are both set to 5 by default. Because the sound quality of an IP phone call can deteriorate if the data is unevenly sent, the switch supports quality of service (QoS) based on IEEE 802.1p CoS. QoS uses classification and scheduling to send network traffic from the switch in a predictable manner.
The Cisco 7960 IP Phone is a configurable device, and you can configure it to forward traffic with an IEEE 802.1p priority. You can configure the switch to trust or override the traffic priority assigned by a Cisco IP Phone.
This network configuration is one way to connect a Cisco 7960 IP Phone.
The Cisco IP Phone contains an integrated three-port 10/100 switch. The ports provide dedicated connections to these devices:
You can configure an access port with an attached Cisco IP Phone to use one VLAN for voice traffic and another VLAN for data traffic from a device attached to the phone. You can configure access ports on the switch to send Cisco Discovery Protocol (CDP) packets that instruct an attached phone to send voice traffic to the switch in any of these ways:
(注) |
In all configurations, the voice traffic carries a Layer 3 IP precedence value (the default is 5 for voice traffic and 3 for voice control traffic). |
The switch can also process tagged data traffic (traffic in IEEE 802.1Q or IEEE 802.1p frame types) from the device attached to the access port on the Cisco IP Phone. You can configure Layer 2 access ports on the switch to send CDP packets that instruct the attached phone to configure the phone access port in one of these modes:
In trusted mode, all traffic received through the access port on the Cisco IP Phone passes through the phone unchanged.
In untrusted mode, all traffic in IEEE 802.1Q or IEEE 802.1p frames received through the access port on the Cisco IP Phone receive a configured Layer 2 CoS value. The default Layer 2 CoS value is 0. Untrusted mode is the default.
(注) |
Untagged traffic from the device attached to the Cisco IP Phone passes through the phone unchanged, regardless of the trust state of the access port on the phone. |
Because a Cisco 7960 IP Phone also supports a connection to a PC or other device, a port connecting the switch to a Cisco IP Phone can carry mixed traffic. You can configure a port to decide how the Cisco IP Phone carries voice traffic and data traffic.
The voice VLAN should be present and active on the switch for the IP phone to correctly communicate on the voice VLAN. Use the show vlan privileged EXEC command to see if the VLAN is present (listed in the display). If the VLAN is not listed, create the voice VLAN.
The Power over Ethernet (PoE) switches are capable of automatically providing power to Cisco pre-standard and IEEE 802.3af-compliant powered devices if they are not being powered by an AC power source.
The Port Fast feature is automatically enabled when voice VLAN is configured. When you disable voice VLAN, the Port Fast feature is not automatically disabled.
If the Cisco IP Phone and a device attached to the phone are in the same VLAN, they must be in the same IP subnet. These conditions indicate that they are in the same VLAN:
The Cisco IP Phone and a device attached to the phone cannot communicate if they are in the same VLAN and subnet but use different frame types because traffic in the same subnet is not routed (routing would eliminate the frame type difference).
Voice VLAN ports can also be these port types:
IEEE 802.1x authenticated port.
(注) |
If you enable IEEE 802.1x on an access port on which a voice VLAN is configured and to which a Cisco IP Phone is connected, the phone loses connectivity to the switch for up to 30 seconds. |
The voice VLAN feature is disabled by default.
When the voice VLAN feature is enabled, all untagged traffic is sent according to the default CoS priority of the port.
The CoS value is not trusted for IEEE 802.1p or IEEE 802.1Q tagged traffic.
You can configure a port connected to the Cisco IP Phone to send CDP packets to the phone to configure the way in which the phone sends voice traffic. The phone can carry voice traffic in IEEE 802.1Q frames for a specified voice VLAN with a Layer 2 CoS value. It can use IEEE 802.1p priority tagging to give voice traffic a higher priority and forward all voice traffic through the native (access) VLAN. The Cisco IP Phone can also send untagged voice traffic or use its own configuration to send voice traffic in the access VLAN. In all configurations, the voice traffic carries a Layer 3 IP precedence value (the default is 5).
You can connect a PC or other data device to a Cisco IP Phone port. To process tagged data traffic (in IEEE 802.1Q or IEEE 802.1p frames), you can configure the switch to send CDP packets to instruct the phone how to send data packets from the device attached to the access port on the Cisco IP Phone. The PC can generate packets with an assigned CoS value. You can configure the phone to not change (trust) or to override (not trust) the priority of frames arriving on the phone port from connected devices.
Follow these steps to set the priority of data traffic received from the non-voice port on the Cisco IP Phone:
コマンドまたはアクション | 目的 | |||
---|---|---|---|---|
ステップ 1 |
configure terminal 例: Switch# configure terminal |
|||
ステップ 2 |
interface
interface-id 例: Switch(config)# interface gigabitethernet1/0/1 |
Specifies the interface connected to the Cisco IP Phone, and enters interface configuration mode. |
||
ステップ 3 |
switchport priority extend {
cos
value |
trust} 例: Switch(config-if)# switchport priority extend trust |
Sets the priority of data traffic received from the Cisco IP Phone access port:
|
||
ステップ 4 |
end 例: Switch(config-if)# end |
|||
ステップ 5 |
show interfaces
interface-id
switchport 例: Switch# show interfaces gigabitethernet1/0/1 switchport |
|||
ステップ 6 |
copy running-config startup-config 例: Switch# copy running-config startup-config |
To display voice VLAN configuration for an interface, use the show interfaces interface-id switchport privileged EXEC command.
This example shows how to configure a port connected to a Cisco IP Phone to use the CoS value to classify incoming traffic and to accept voice and data priority traffic tagged with VLAN ID 0:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet1/0/1 Switch(config-if)# mls qos trust cos Switch(config-if)# switchport voice vlan dot1p Switch(config-if)# end
To return the port to its default setting, use the no switchport voice vlan interface configuration command.
This example shows how to enable switch port voice detect on a Cisco IP Phone:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet 1/0/1 Switch(config-if)# switchport voice? detect detection enhancement keyword vlan VLAN for voice traffic Switch(config-if)# switchport voice detect? cisco-phone Cisco IP Phone Switch(config-if)# switchport voice detect cisco-phone? full-duplex Cisco IP Phone Switch(config-if)# switchport voice detect cisco-phone full-duplex full-duplex full duplex keyword Switch(config-if)# end
This example shows how to disable switchport voice detect on a Cisco IP Phone:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet 1/0/1 Switch(config-if)# no switchport voice detect cisco-phone Switch(config-if)# no switchport voice detect cisco-phone full-duplex
This example shows how to configure a port connected to a Cisco IP Phone to not change the priority of frames received from the PC or the attached device:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet1/0/1 Switch(config-if)# switchport priority extend trust Switch(config-if)# end
After configuring voice VLANs, you can configure the following:
Related Topic | Document Title |
---|---|
For complete syntax and usage information for the commands used in this chapter. |
Standard/RFC | Title |
---|---|
— |
— |
MIB | MIBs Link |
---|---|
All supported MIBs for this release. |
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: |
Description | Link |
---|---|
The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies. To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password. |
Release | Modification |
---|---|
Cisco IOS 15.0(2)EX1 |
This feature was introduced. |
目次
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
The following are the prerequisites for voice VLANs:
Voice VLAN configuration is only supported on switch access ports; voice VLAN configuration is not supported on trunk ports.
(注) |
Trunk ports can carry any number of voice VLANs, similar to regular VLANs. The configuration of voice VLANs is not supported on trunk ports. |
Before you enable voice VLAN, we recommend that you enable QoS on the switch by entering the mls qos global configuration command and configure the port trust state to trust by entering the mls qos trust cos interface configuration command. If you use the auto-QoS feature, these settings are automatically configured.
You must enable CDP on the switch port connected to the Cisco IP Phone to send the configuration to the phone. (CDP is globally enabled by default on all switch interfaces.)
The voice VLAN feature enables access ports to carry IP voice traffic from an IP phone. When the switch is connected to a Cisco 7960 IP Phone, the phone sends voice traffic with Layer 3 IP precedence and Layer 2 class of service (CoS) values, which are both set to 5 by default. Because the sound quality of an IP phone call can deteriorate if the data is unevenly sent, the switch supports quality of service (QoS) based on IEEE 802.1p CoS. QoS uses classification and scheduling to send network traffic from the switch in a predictable manner.
The Cisco 7960 IP Phone is a configurable device, and you can configure it to forward traffic with an IEEE 802.1p priority. You can configure the switch to trust or override the traffic priority assigned by a Cisco IP Phone.
You can configure an access port with an attached Cisco IP Phone to use one VLAN for voice traffic and another VLAN for data traffic from a device attached to the phone. You can configure access ports on the switch to send Cisco Discovery Protocol (CDP) packets that instruct an attached phone to send voice traffic to the switch in any of these ways:
(注) |
In all configurations, the voice traffic carries a Layer 3 IP precedence value (the default is 5 for voice traffic and 3 for voice control traffic). |
The switch can also process tagged data traffic (traffic in IEEE 802.1Q or IEEE 802.1p frame types) from the device attached to the access port on the Cisco IP Phone. You can configure Layer 2 access ports on the switch to send CDP packets that instruct the attached phone to configure the phone access port in one of these modes:
In trusted mode, all traffic received through the access port on the Cisco IP Phone passes through the phone unchanged.
In untrusted mode, all traffic in IEEE 802.1Q or IEEE 802.1p frames received through the access port on the Cisco IP Phone receive a configured Layer 2 CoS value. The default Layer 2 CoS value is 0. Untrusted mode is the default.
(注) |
Untagged traffic from the device attached to the Cisco IP Phone passes through the phone unchanged, regardless of the trust state of the access port on the phone. |
Because a Cisco 7960 IP Phone also supports a connection to a PC or other device, a port connecting the switch to a Cisco IP Phone can carry mixed traffic. You can configure a port to decide how the Cisco IP Phone carries voice traffic and data traffic.
The voice VLAN should be present and active on the switch for the IP phone to correctly communicate on the voice VLAN. Use the show vlan privileged EXEC command to see if the VLAN is present (listed in the display). If the VLAN is not listed, create the voice VLAN.
The Power over Ethernet (PoE) switches are capable of automatically providing power to Cisco pre-standard and IEEE 802.3af-compliant powered devices if they are not being powered by an AC power source.
The Port Fast feature is automatically enabled when voice VLAN is configured. When you disable voice VLAN, the Port Fast feature is not automatically disabled.
If the Cisco IP Phone and a device attached to the phone are in the same VLAN, they must be in the same IP subnet. These conditions indicate that they are in the same VLAN:
The Cisco IP Phone and a device attached to the phone cannot communicate if they are in the same VLAN and subnet but use different frame types because traffic in the same subnet is not routed (routing would eliminate the frame type difference).
Voice VLAN ports can also be these port types:
IEEE 802.1x authenticated port.
(注) |
If you enable IEEE 802.1x on an access port on which a voice VLAN is configured and to which a Cisco IP Phone is connected, the phone loses connectivity to the switch for up to 30 seconds. |
(注) |
When you enable port security on an interface that is also configured with a voice VLAN, you must set the maximum allowed secure addresses on the port to two plus the maximum number of secure addresses allowed on the access VLAN. When the port is connected to a Cisco IP Phone, the phone requires up to two MAC addresses. The phone address is learned on the voice VLAN and might also be learned on the access VLAN. Connecting a PC to the phone requires additional MAC addresses. |
The voice VLAN feature is disabled by default.
When the voice VLAN feature is enabled, all untagged traffic is sent according to the default CoS priority of the port.
The CoS value is not trusted for IEEE 802.1p or IEEE 802.1Q tagged traffic.
You can configure a port connected to the Cisco IP Phone to send CDP packets to the phone to configure the way in which the phone sends voice traffic. The phone can carry voice traffic in IEEE 802.1Q frames for a specified voice VLAN with a Layer 2 CoS value. It can use IEEE 802.1p priority tagging to give voice traffic a higher priority and forward all voice traffic through the native (access) VLAN. The Cisco IP Phone can also send untagged voice traffic or use its own configuration to send voice traffic in the access VLAN. In all configurations, the voice traffic carries a Layer 3 IP precedence value (the default is 5).
コマンドまたはアクション | 目的 | |||
---|---|---|---|---|
ステップ 1 |
configure terminal 例: Switch# configure terminal |
|||
ステップ 2 |
interface
interface-id 例: Switch(config)# interface gigabitethernet1/0/1 |
Specifies the interface connected to the phone, and enters interface configuration mode. |
||
ステップ 3 |
mls qos trust cos 例: Switch(config-if)# mls qos trust cos |
Configures the interface to classify incoming traffic packets by using the packet CoS value. For untagged packets, the port default CoS value is used.
|
||
ステップ 4 |
switchport voice vlan {vlan-id | dot1p | none | untagged } 例: Switch(config-if)# switchport voice vlan 125 |
Configures how the Cisco IP Phone carries voice traffic:
|
||
ステップ 5 |
end 例:
Switch(config-if)# end
|
|||
ステップ 6 | Use one of the following:
例: Switch# show interfaces gigabitethernet1/0/1 switchport Switch# show running-config interface gigabitethernet1/0/1 |
Verifies your voice VLAN entries or your QoS and voice VLAN entries. |
||
ステップ 7 |
copy running-config startup-config 例: Switch# copy running-config startup-config |
You can connect a PC or other data device to a Cisco IP Phone port. To process tagged data traffic (in IEEE 802.1Q or IEEE 802.1p frames), you can configure the switch to send CDP packets to instruct the phone how to send data packets from the device attached to the access port on the Cisco IP Phone. The PC can generate packets with an assigned CoS value. You can configure the phone to not change (trust) or to override (not trust) the priority of frames arriving on the phone port from connected devices.
Follow these steps to set the priority of data traffic received from the non-voice port on the Cisco IP Phone:
コマンドまたはアクション | 目的 | |||
---|---|---|---|---|
ステップ 1 |
configure terminal 例: Switch# configure terminal |
|||
ステップ 2 |
interface
interface-id 例: Switch(config)# interface gigabitethernet1/0/1 |
Specifies the interface connected to the Cisco IP Phone, and enters interface configuration mode. |
||
ステップ 3 |
switchport priority extend {
cos
value |
trust} 例: Switch(config-if)# switchport priority extend trust |
Sets the priority of data traffic received from the Cisco IP Phone access port:
|
||
ステップ 4 |
end 例: Switch(config-if)# end |
|||
ステップ 5 |
show interfaces
interface-id
switchport 例: Switch# show interfaces gigabitethernet1/0/1 switchport |
|||
ステップ 6 |
copy running-config startup-config 例: Switch# copy running-config startup-config |
This example shows how to configure a port connected to a Cisco IP Phone to use the CoS value to classify incoming traffic and to accept voice and data priority traffic tagged with VLAN ID 0:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet1/0/1 Switch(config-if)# mls qos trust cos Switch(config-if)# switchport voice vlan dot1p Switch(config-if)# end
To return the port to its default setting, use the no switchport voice vlan interface configuration command.
This example shows how to enable switch port voice detect on a Cisco IP Phone:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet 1/0/1 Switch(config-if)# switchport voice? detect detection enhancement keyword vlan VLAN for voice traffic Switch(config-if)# switchport voice detect? cisco-phone Cisco IP Phone Switch(config-if)# switchport voice detect cisco-phone? full-duplex Cisco IP Phone Switch(config-if)# switchport voice detect cisco-phone full-duplex full-duplex full duplex keyword Switch(config-if)# end
This example shows how to disable switchport voice detect on a Cisco IP Phone:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet 1/0/1 Switch(config-if)# no switchport voice detect cisco-phone Switch(config-if)# no switchport voice detect cisco-phone full-duplex
This example shows how to configure a port connected to a Cisco IP Phone to not change the priority of frames received from the PC or the attached device:
Switch# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet1/0/1 Switch(config-if)# switchport priority extend trust Switch(config-if)# end
Description | Link |
---|---|
The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies. To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password. |