Using Bootp / Dhcp; Bootp/Dhcp Server Parameters; Using Dhcp - AudioCodes Mediant 1000 User Manual

SIP User's Manual
7

Using BootP / DHCP

The Mediant 1000 uses the Bootstrap Protocol (BootP) and the Dynamic Host
Configuration Protocol (DHCP) to obtain its networking parameters and configuration
automatically after it is reset. BootP and DHCP are also used to provide the IP address of a
TFTP server on the network, and files (cmp and ini) to be loaded into memory.
DHCP is a communication protocol that automatically assigns IP addresses from a central
point. BootP is a protocol that enables a device to discover its own IP address. Both
protocols have been extended to enable the configuration of additional parameters specific
to the Mediant 1000.
Note:
7.1

BootP/DHCP Server Parameters

BootP/DHCP can be used to provision the following parameters (included in the
BootP/DHCP reply). Note that only the IP address and subnet mask are mandatory:
IP address, subnet mask - These mandatory parameters are sent to the Mediant 1000
every time a BootP/DHCP process occurs.
Default gateway IP address - An optional parameter that is sent to the Mediant 1000
only if configured in the BootP/DHCP server.
TFTP server IP address - An optional parameter that contains the address of the
TFTP server from which the firmware (cmp) and ini files are loaded.
DNS server IP address (primary and secondary) - Optional parameters that contain
the IP addresses of the primary and secondary DNS servers. These parameters are
available only in DHCP and from Boot version 1.92.
Syslog server IP address - An optional parameter that is sent to the Mediant 1000 only
if configured. This parameter is available only in DHCP.
SIP server IP address – Two optional parameters that are sent to the Mediant 1000
only if configured. These parameters are available only in DHCP.
Firmware file name – An optional parameter that contains the name of the firmware
file to be loaded to the gateway via TFTP.
ini file name - An optional parameter that contains the name of the ini file to be loaded
to the gateway via TFTP.
7.2

Using DHCP

When the gateway is configured to use DHCP (DHCPEnable = 1), it attempts to contact the
local DHCP server to obtain the networking parameters (IP address, subnet mask, default
gateway, primary/secondary DNS server and two SIP server addresses). These network
parameters have a 'time limit'. After the time limit expires, the gateway must 'renew' its
lease from the DHCP server.
Note that if the DHCP server denies the use of the gateway's current IP address and
specifies a different IP address (according to RFC 1541), the gateway must change its
networking parameters. If this happens while calls are in progress, they are not
automatically rerouted to the new network address (since this function is beyond the scope
of a VoIP gateway). Therefore, administrators are advised to configure DHCP servers to
allow renewal of IP addresses.
Version 5.0
BootP is normally used to initially configure the Mediant 1000. Thereafter,
BootP is no longer required as all parameters can be stored in the
gateway's non-volatile memory and used when BootP is inaccessible.
BootP can be used again to change the IP address of the Mediant 1000
(for example).
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7. Using BootP / DHCP
December 2006