HP V1910 Configuring the voice VLAN

Security mode and normal mode of voice VLANs

Depending on their inbound packet filtering mechanisms, voice VLAN-enabled port can operate in the following modes:

∙Normal mode: In this mode, voice VLAN-enabled ports receive packets carrying the voice VLAN tag and forward packets in the voice VLAN without checking their source MAC addresses against the OUI addresses configured for the device. If the PVID of the port is the voice VLAN and the port works in manual VLAN assignment mode, the port forwards all received untagged packets in the voice VLAN. In normal mode, the voice VLANs are vulnerable to traffic attacks. Vicious users may forge a large amount of voice packets and send them to the device to consume the voice VLAN bandwidth, affecting normal voice communication.

∙Security mode: In this mode, only voice packets whose source MAC addresses match the recognizable OUI addresses can pass through the voice VLAN-enabled inbound port, but all other packets are dropped.

In a safe network, you can configure the voice VLANs to operate in normal mode, reducing the consumption of system resources due to source MAC addresses checking.

HP does not recommend you transmit both voice traffic and non-voice traffic in a voice VLAN. If you have to, ensure that the voice VLAN security mode is disabled.

1.How a voice VLAN-enable port processes packets in security/normal mode

Voice VLAN mode	Packet type	Packet processing mode
	Untagged packets	If the source MAC address of a packet matches an
		OUI address configured for the device, it is
	Packets carrying the voice
Security mode		forwarded in the voice VLAN; otherwise, it is
	VLAN tag	dropped.
	Packets carrying other tags	Forwarded or dropped depending on whether the
		port allows packets of these VLANs to pass through
	Untagged packets	The port does not check the source MAC addresses
		of inbound packets. In this way, both voice traffic
	Packets carrying the voice	and non-voice traffic can be transmitted in the voice
Normal mode		VLAN.
	VLAN tag
	Packets carrying other tags	Forwarded or dropped depending on whether the
		port allows packets of these VLANs to pass through

Configuring the voice VLAN

Configuration task list

Before configuring the voice VLAN feature, you must create the corresponding VLAN and configure the link type of each port to be assigned to the VLAN. VLAN 1 is the default VLAN, and you cannot create it or configure it as a voice VLAN. For more information about port link types, see the chapter “Port management configuration”.

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