Installation manual

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CLI - This example applies a service policy to an ingress interface.
VoIP Traffic Configuration
When IP telephony is deployed in an enterprise network, it is recommended to isolate the
Voice over IP (VoIP) network traffic from other data traffic. Traffic isolation can provide
higher voice quality by preventing excessive packet delays, packet loss, and jitter. This is
best achieved by assigning all VoIP traffic to a single Voice VLAN.
The use of a Voice VLAN has several advantages. It provides security by isolating the
VoIP traffic from other data traffic. End-to-end QoS policies and high priority can be
applied to the VoIP VLAN traffic across the network, guaranteeing the bandwidth it needs.
The VLAN isolation also protects against disruptive broadcast and multicast traffic that
can seriously affect voice quality.
The switch allows you to specify a Voice VLAN for the network and set a CoS priority for
the VoIP traffic. VoIP traffic can be detected on switch ports by using the source MAC
address of packets, or by using LLDP (IEEE 802.1AB) to discover connected VoIP
devices. When VoIP traffic is detected on a configured port, the switch automatically
assigns the port as a tagged member the Voice VLAN. Alternatively, switch ports can be
manually configured.
Configuring VoIP Traffic
To configure the switch for VoIP traffic, first enable the automatic detection of VoIP
devices attached to switch ports, then set the Voice VLAN ID for the network. The Voice
VLAN aging time can also be set to remove a port from the Voice VLAN when VoIP traffic
is no longer received on the port.
Command Attributes
• Auto Detection Status – Enables the automatic detection of VoIP traffic on switch
ports. (Default: Disabled)
• Voice VLAN ID – Sets the Voice VLAN ID for the network. Only one Voice VLAN is
supported and it must already be created on the switch. (Range: 1-4094)
• Voice VLAN Aging Time – The time after which a port is removed from the Voice VLAN
when VoIP traffic is no longer received on the port.
(Range: 5-43200 minutes; Default: 1440 minutes).
Note:
The Voice VLAN ID cannot be modified when the global Auto Detection Status is
enabled.
Console(config)#interface ethernet 1/5 4-186
Console(config-if)#service-policy input rd_policy#3 4-310
Console(config-if)#