Dhcp Option Reclassification - Mitel mivoice business Engineering Manualline

DHCP OPTION RECLASSIFICATION

Mitel's legacy IP device configuration approach, using DHCP options 128 – 135 is still
supported, but the preferred methods based on either DHCP options 124/125 or 60/43 are
recommended. The standards based options (124/125 and 60/43) will remove potential DHCP
conflict with other devices and manufactures that may be using the same DHCP server for
optional information.
The following three points contain general information about the supported Client DHCP
Discovery method:
1. RFC 3925 Vendor-Identifying Option exchange (options 124 / 125).
Option 125 is used to return the vendor-specific configuration in response to option 124
containing the Mitel enterprise number (1027 decimal).
For MiVoice IP Phones, this option will contain the following sub-fields:
- enterprise-number = 1027 (decimal), the IANA-registered Mitel Enterprise Number
- data-len = length of the following configuration string
- vendor-class-data = Mitel-specific configuration string, as defined in "Vendor
information data format (options 125 and 43)" on page 247.
2. RFC 2132 Vendor Class based exchange (options 60 / 43)
Option 43 is used to return the vendor-specific configuration in response to option 60
containing the Mitel identification string ("ipphone.mitel.com").
For MiVoice IP Phones, this option will contain only the following sub-fields:
- vendor-specific-information = Mitel-specific configuration string, as defined in "Vendor
information data format (options 125 and 43)" on page 247.
3. Legacy Options 128-135 (for backwards compatibility only)
In this response, the DHCP server returns options 128 – 135 shown in Table 72, and any
Mitel partner-specific options. If the 3300 embedded DHCP does not receive option 124
or option 60, it will also respond this way, if configured to do so for these options. If these
options were previously configured in the 3300 DHCP server, they will already be in place
(they are not deleted as a result of an upgrade), however they may need to be configured
in a new installation if the IP Phones on the site were previously on a system with Active
Software Release of 7.0 or earlier. The options will be needed to allow these IP Phones to
be upgraded when they first boot up.
DHCP
OPTION
3
6
44
120
128
129
130
Table 72: Mitel-Internal current DHCP Option Usage
FIELD TYPE DESCRIPTION
IP address Default Gateway (Router) IP address
IP address Preferred DNS IP address (used by Webset, PDA phone only)
IP address Preferred WINS address (used by PDA phone only)
IP address SIP outbound proxy address
IP address list TFTP Server IP address (for software loads)
IP address list ICP IP address list
string Mitel server discrimination string: "MITEL IP PHONE"
Network Configuration Specifics
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