Specifications

Engineering Guidelines
134
• Using RSTP reduces disconnection time to approximately 3 seconds, which has a much
smaller effect on IP phone operation and is the preferred setting throughout the network.
• STP and RSTP in the various 3300 ICP Controllers:
- The Spanning Tree Protocol (STP) is supported on the LX controller; the STP
parameters on this platform is predefined and are not user-configurable
- The Rapid Reconfiguration of Spanning Tree Protocol (RSTP) is supported on the
MXe, AX and Cxi controllers and the user has the ability to configure RSTP
parameters on these platforms.
• In the event that an L2 switch vendor does not adhere to the STP/RSTP or CDP protocols
correctly, there could be issues that prevent E911 from functioning as required. At the time
of writing, Mitel is not aware of any specific L2 switches that fail to comply with STP/RSTP
or CDP.
• As noted under “Teleworker devices” on page 131, Teleworker Solution only supports E911
services when used with a properly configured LIM and when the 3300 ICP is correctly
programmed.
In all other cases, the Teleworker Solution does not directly support E911 services. The
System Administrator should note that devices that are in Teleworker mode and that are
connected outside of the corporate firewall will not have 911 calls blocked. 911 calls placed
from such devices may report an incorrect CESID or may be outside the PSAPs coverage
area.
• As noted under “CESID auto updates, unsupported cConfigurations” on page 132, the
MiCollab Client Softphone and the Wireless phones do not support E911 services.
• Refer to the sections on SIP Trunking and Satellite Office Solution with SIP Gateway for
details regarding 911 services with these applications.
• When provisioning users with 911 services, the System Administrator should consider:
- employing redundant trunks for PSTN access
- using uninterruptible power supplies or redundant mains power for the ICP and the
phones
- deploying the 3300 ICPs in a resilient fashion.
Note: More details on Rapid Spanning Tree configurations can be found in the 3300
ICP Resiliency Guide.
Note: The CX 3300 ICP system supports only one LAN connection. In this case network
resiliency and multiple network connections are not available, but these CX 3300 ICPs
can be combined with other units as part of a resilient cluster.