Specifications

Chapter 3 - IP Address and Network Configuration Vendor and Site Specific DHCP Options
54
Mediatrix 4100
Figure 14: Layout for Encapsulated Vendor Specific Options
Figure 15
is an example of a vendor specific option containing an msHost IP address (192.168.1.2).
Figure 15: Example of Encapsulated Vendor Specific Option
Mediatrix units store two types of information in vendor specific options: IP addresses with optional port
number and FQDNs with optional port number. The layout for storing IP addresses is explained in section
“
Entering IP Addresses” on page 55. The layout for storing FQDNs is explained in section “Entering FQDNs”
on page 56.
Vendor Class ID
When using the vendor specific option, first define a Vendor Class ID for the Mediatrix 4100 (not supported in
Windows NT servers). A Vendor Class ID can be used by DHCP clients to identify their vendor type and
configuration. When using this option, vendors can define their own specific identifier values to convey a
particular hardware or operating system configuration or other identifying information.
Where vendor classes are used, the DHCP server responds to identifying clients by using option code 43, the
reserved option type for returning vendor specific information to the client.
DHCP servers that do not interpret this option type are expected to ignore it when it is specified by clients.
Please refer to your DHCP server’s documentation to learn how to create a new vendor class.
Creating Vendor Specific Information
Once the Vendor ID Class is created, place the proper values in the 43 option of the DHCP server. The 43
option contains sub-options that are encapsulated (according to the format described in RFC 2132).
If the option is not in the DHCP server, the Mediatrix 4100 uses an invalid value (0.0.0.0:0).
Please refer to your DHCP server’s documentation to learn how to create vendor specific information. See
“Entering IP Addresses” on page 55 for more details on the syntax to use.
Site Specific Options
Site specific options are non-standard DHCP options specific to the network where the Mediatrix 4100 is used.
You are responsible to allocate an option number (between 128 and 254) for each information element to be
stored.
Mediatrix units store two types of information in site specific options: IP addresses with optional port number
and FQDNs with optional port number. The layout for storing IP addresses is explained in section “Entering IP
Addresses” on page 55. The layout for storing FQDNs is explained in section “Entering FQDNs” on page 56.
Figure 16
is an example of site specific option #146, containing address 192.168.0.1.
Figure 16: Site Specific Option Example
When using the site specific option, you can place the values in the site specific options of your choice in the
DHCP server. You must then enter the values in the proper MIB variables.
43 Len Code1 Len1 Data1 Data1 … Code2 Len2 Data2 Data2 …
43 6 200 4 192 168 1 2
Note: The class to add is Mediatrix 4108, Mediatrix 4116, or Mediatrix 4124, depending on your unit model.
Standards Supported RFC 2132 – DHCP Options and BOOTP Vendor Extensions, section 2
(“BOOTP Extension/DHCP Option Field Format”).
146 4 192 168 0 1