Nortel Networks NN43001-504 manual Dhcp server options, Dhcp options

184Appendix B Troubleshooting WLAN IP Telephony installations

DHCP server options

The DHCP server options known to work in almost every situation are 3, 7, 42, 66, 128, 151, and 152:

•DHCP Option 3—the Default Gateway

•DHCP Option 7—the Syslog Server

•DHCP Option 42—the Time Server

•DHCP Option 60—the Class Identifier

•DHCP Option 66—the IP address of the TFTP Server

•DHCP Option 151—the IP address of the WLAN IP Telephony Manager 2245

•DHCP Option 152—the IP address for the optional WLAN Application Gateway 2246

DHCP options have the same format as the BOOTP vendor extensions. Options can be fixed length or variable length. All options begin with a tag byte, which uniquely identifies the option. Fixed length options without data consist of only a tag byte. The value of the length byte does not include the tag and length fields.

Options containing NVT ASCII data (ideally) do not include a trailing NULL; however, the receiver of such options must be prepared to delete trailing NULLs if they exist. The receiver must not require that a trailing NULL be included in the data. With some variable-length options, the length field is a constant but it still must be specified.

DHCP options

This section provides the IEEE definitions of the DHCP options. The term SHOULD, as used in this section, is to be interpreted as described in [RFC2119].

DHCP option 1: Subnet Mask. Length: 6 bytes

This option specifies the client’s subnet mask. If both the Subnet Mask and the router option are specified in a DHCP reply, this option MUST be first.

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Nortel Communication Server 1000

WLAN IP Telephony Installation and Commissioning

NN43001-504 01.02 Standard

Release 5.0 15 June 2007

Copyright © 2004-2007, Nortel Networks