c02.fm
A31003-S2000-R102-16-7620, 02/2016
Provisioning Service, Developer’s Guide
17
Nur für den internen Gebrauch
DHCP
Extended Configuration
2.2
Extended Configuration
Additionally, it is possible to provide these parameters by DHCP, as an alternative to setting
them manually, or via provisioning service.
•
SNTP IP Address (option #42 "NTP Servers")
: IP address or hostname of the SNTP
server to be used by the phone.
•
Timezone offset (option #2 "Time Offset")
: Offset in seconds in relationship to the UTC
time provided by the SNTP server.
•
SIP server (option #120 "SIP Servers DHCP Option")
: The SIP server to be used by the
phone.
•
Domain name (option #15 "Domain Name")
: The name of the DNS domain wherein the
phone is residing.
•
VLAN ID
: Necessary if the phone operates in a VLAN (Virtual LAN). This parameter can
be provided by means of a "vendor-encapsulated-options" option.
•
Provisioning service contact address
: Enables the phone to contact the provisioning
service immediately on startup. This parameter can be provided by means of a
vendor-encapsulated-options
option.
2.3
Example DHCP server configuration
The following description demonstrates by example how a ISC DHCP server can be configured
in order to build up a working infrastructure for OpenStage phones or OpenScape Desk Phone
IP.
The configuration example has been tested with ISC DHCP server version 3 running on Debian
Linux (package: dhcp3-server).
On startup, the OpenStage phone or OpenScape Desk Phone IP sends a DHCP discovery
message which contains the
vendor-class-identifier
option. The fixed value is
Op-
tiIpPhone
. This identifier is used by the DHCP server to send a specified set of sub-options
to each OpenStage phone or OpenScape Desk Phone IP by means of vendor encapsulated
options. The
vendor-encapsulated-options
option allows for defining custom-made op-
tions in either a single series of bytes or a sequence of parameters which is constructed from:
1. the single-byte vendor-specific option code;
2. the single-byte length indication for the option data (the length does not include itself or the
option code);
3. the data itself in as many bytes of data as are specified in the length indication.