Mitel MiVOICE BUSINESS, Engineering Manualline

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Network Configuration Concepts
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The IP devices connected to the port examples above are
• Ports 1 though 4: Dual-port phones with PCs.
• Port 5: Interconnected network switches (only tagged data allowed within network).
• Port 6: Not used with this application. Untagged data on this link goes to VLAN4 only.
• Port 7: 3300 ICP controller, or similar voice applications such as a Mitel Speech Server
(formerly Speak@Ease).
• Ports 8 and 9: PCs.
• Port 10: Router with virtual ports (similar to a connection between switches).
• Port 11: Router port that physically separates VLANs (the data VLAN).
• Port 12: Router port that physically separates VLANs (the voice VLAN).
More details on configuring different HP network switches can be found in HP ProCurve
Networking IP Telephony Solution Design Guide and HP ProCurve Networking IP Telephony
Solution Implementation Guide on Mitel OnLine.
Refer to http://www.hp.com/rnd/solutions/convergence.htm for examples of how to set up HP
switches in a VoIP environment.
WAN LAYER 3 PRIORITY
A number of different WAN technologies provide data routing with different priorities and Service
Level Agreements (SLA). Most of these deal with the WAN technology, but most rely on
information being presented in the Layer 3 Type-of-Service (TOS) field.
The Type-of-Service field has undergone some name and function changes. This field is now
also known as Differentiated Services Code Point (DSCP) or DiffServ. The DiffServ uses the
precedence and some of the TOS bits (TOS instead of Type of Service field) to provide 64
different service levels. See Figure 30 on page 213 for the location of the Type-of-Service field.
Voice will typically be sent in the Expedited Forwarding (EF) queue which is represented by a
DSCP value of 46.
The DSCP value is programmed using DHCP server option (see “DHCP Option
Reclassification” on page 245). This is picked up by the IP phones. The default Mitel values for
DSCP was previously fixed at 44 to allow backward compatibility with older TOS based routers.
However, today, 46 is the expected value to be used. A DSCP value of 44 will still be directed
to a high priority queue, but 46 is handled in a more “Expedited” manner. It is recommended
that to provide for product at different levels routers (default gateways) map DSCP44 to
DSCP46. The alternative is to map DSCP44 to the EF queue, but then this needs to be
programmed in all routers. Note that the DSCP value can still be programmed to 44 to maintain
backward compatibility. Current releases of software (MCD 4.0 upwards) use a default DSCP
value of 46, while the older IP sets and software may also use a default DSCP value of 44. An
example of programming needed for a router is given in the appendix (see page 312 and
page 315).
Note: Using VLAN 0 with HP is not recommended. However, it is possible to extend
VLAN numbering up to a maximum of 4093.