Mitel MiVOICE BUSINESS, Engineering Manualline

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Engineering Guidelines
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this range. As a general rule, VLAN 0 is treated in different ways by different vendors.
The recommendation is
not to use VLAN 0. Cisco also reserves VLAN 1000 and
upward for Cisco purposes, so ensure there is not a conflict when using these higher
VLAN numbers.
• Multi-VLAN port
- Cisco devices provide this as another port configuration. However, on some of the
access switches it is not possible to use multi-VLAN ports and trunk ports on the same
unit. Unfortunately, the multi-VLAN port type is needed in order to work with other
vendor products. A trunk port can be used, but it also removes tagging from the
configured native VLAN, which may not be what is required. An example is a port
configured with the native_VLAN to 1. On ingress, tagging is added, but on egress it
is removed. Tagging information should be maintained through the network, only
being modified at the access points. Removing tagging between switches is not
desirable. There are two possible ways out of this situation:
a. Run Cisco ISL between the two units (but then they both need to be Cisco).
or
b. Create a dummy native_VLAN (tag native_VLAN) that is not used anywhere else
in the network to ensure compatibility with other vendor units and allow products
to be mixed. The dummy VLAN does not carry data since there are no end devices
configured with this VLAN. This effectively turns the trunk port into a multi-VLAN
port for the desired VLAN connections.
HP port examples
The HP switch uses a similar RS232 connection, but the user interface is more menu-driven
making the configuration more intuitive. The following figure shows a typical screen display.
Figure 31: HP Screen Display Example
The default_vlan is VLAN1. The VLAN numbers are assigned names to help follow which
function is assigned to which VLAN. The voice_vlan is VLAN2, the video_vlan is VLAN3, and
test4 is VLAN4. The default VLAN is used by the data devices and also by the IP phones when
they first start up and look for their correct VLAN configuration. (See the section “Startup
Sequence for Phones” on page 234.)