Avaya 555-245-600 사용자 설명서

Virtual Local Area Networks (VLANs) are an often-misunderstood concept. This section begins 
by defining VLANs, and then addresses configurations that require the Avaya IP Telephone to 
connect to an Ethernet switch port that is configured for multiple VLANs. The IP Telephone is on 
one VLAN, and a personal computer that is connected to the telephone is on a separate VLAN. 
Three sets of configurations are given: Avaya C360, Cisco CatOS, and some Cisco IOS.

With simple Ethernet switches, the entire switch is one Layer 2 broadcast domain that usually 
contains one IP subnetwork (Layer 3 broadcast domain). Think of a single VLAN (on a 
VLAN-capable Ethernet switch) as being equivalent to a simple Ethernet switch. A VLAN is a 
logical Layer 2 broadcast domain that typically contains one IP subnetwork. Therefore, multiple 
VLANs contain logically separated subnetworks. This arrangement is analogous to multiple 
switches being physically separated subnetworks. A Layer 3 routing process is required to route 
between VLANs, just as one is required to route between subnetworks. This routing process 
can take place on a connected router or a router module within a Layer 2/Layer 3 Ethernet 
switch. If no routing process is associated with a VLAN, devices on that VLAN can only 
communicate with other devices on the same VLAN.

Port VLAN and native VLAN are synonymous terms. The IEEE 802.1Q standard and most 
Avaya switches use the term port VLAN, but Cisco switches use the term native VLAN. Issue 
the show trunk command on C360s and CatOS Catalysts to see which term is used in the 
display output.
Every port has a port VLAN or a native VLAN. Unless otherwise configured, it is VLAN 1 by 
default. It can be configured on a per-port basis with the commands in 

.

All untagged Ethernet frames (with no 802.1Q tag, for example, from a personal computer) are 
forwarded on the port VLAN or the native VLAN. This is true even if the Ethernet switch port is 
configured as an 802.1Q trunk, or otherwise configured for multiple VLANs. For more 
information, see