Programming instructions

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Installation Planner
• IP Routing form
- When the CXi/MXe receives a packet from a host on the LAN, it
checks the table. If a route is found on the Network List, the
CXi/MXe forwards the packet to the system Gateway or a router
connected to the local subnet. If no route is found, the CXi/MXe
forwards the packet to the internet through its WAN interface.
CXi/MXe VLAN Behavior
• Default VLAN 1
In the default case where the CXi/MXe is on the default VLAN, the
CXi/MXe accepts tagged VLAN 1 frames and untagged frames. Any
non-VLAN 1 tagged frames are dropped. The CXi/MXe treats
untagged frames as VLAN 1 frames. The CXi/MXe prioritizes traffic
based on the priority tag and maintains two priority queues. The low
priority queue is for untagged frames and tagged VLAN 1 frames with
priority 0-3. The high priority queue is for tagged VLAN 1 frames with
priority 4-7. Traffic in the high priority queue is processed first. On
egress, all traffic on all ports is untagged with the exception of port 17
on the CXi and the two LAN ports on the MXe, where the user has the
option to tag the traffic via the “VLAN Tags on Trunk Ports” parameter.
• Voice VLAN
In order for the phones to operate on the Voice VLAN, the CXi/MXe L2
Switch must also be on the same Voice VLAN, or unknown VLAN
frames will be dropped. With the introduction of Voice VLAN support,
the CXi/MXe will accept untagged frames and tagged VLAN 1 or Voice
VLAN frames. All other VLAN tagged frames will be dropped. Priority
queues are maintained as described above, but in this case, for Voice
VLAN tagged traffic. On egress, Voice VLAN traffic remains tagged on
all ports. Untagged frames are treated as VLAN 1 and forwarded to an
external router.
Installation
The traditional installation remains the same as for the MX and LX
controllers because the CXi and MXe rely on external routers to perform
VLAN routing just as the CX, MX, and LX do.
The main difference is that the CXi and MXe maintain Voice VLAN tags on
egress. An externally managed L2 switch connected to the CXi/MXe uplink
port(s) must tag Voice VLAN traffic unlike the setup for the other controllers
that require untagged Voice VLAN traffic.