Protocols And Standards - HP 10500 Series Configuration Manual

Sub-option 1—Contains the user-specified access node identifier (ID of the device that adds
Option 82 in DHCP messages), and the type, number, and VLAN ID of the interface that
received the client's request. The VLAN ID field has a fixed length of 2 bytes. All the other
padding contents of sub-option 1 are length variable. See
Figure 25 Sub-option 1 in verbose padding format
Sub-option 2—Contains the MAC address of the DHCP relay agent interface or the MAC address of the
DHCP snooping device that received the client's request. It has the same format as that in normal
padding format. See
Option 184
Option 184 is a reserved option. You can define the parameters in the option as needed. The device
supports Option 184 carrying voice related parameters, so a DHCP client with voice functions can get
voice parameters from the DHCP server.
Option 184 has the following sub-options:
Sub-option 1—Specifies the IP address of the primary network calling processor, which serves as
•
the network calling control source and provides program download services.
Sub-option 2—Specifies the IP address of the backup network calling processor. DHCP clients
•
contact the backup processor when the primary one is unreachable.
• Sub-option 3—Specifies the voice VLAN ID and the result whether or not the DHCP clients takes this
ID as the voice VLAN.
Sub-option 4—Specifies the failover route that includes the IP address and the number of the target
•
user. A Session Initiation Protocol (SIP) user uses this IP address and number to directly establish a
connection to the target SIP user when both the primary and backup calling processors are
unreachable.
For Option 184, sub-option 1 must be defined to make other sub-options take effect.

Protocols and standards

RFC 2131, Dynamic Host Configuration Protocol
•
RFC 2132, DHCP Options and BOOTP Vendor Extensions
•
RFC 1542, Clarifications and Extensions for the Bootstrap Protocol
•
RFC 3046, DHCP Relay Agent Information Option
•
• RFC 3442, The Classless Static Route Option for Dynamic Host Configuration Protocol (DHCP)
version 4
Figure 24.
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Figure 25.