Configuration Example Using Dhcp Relay Option 82 To Pass Ieee 802.1P Values To Dhcp Servers - Juniper JUNOSE SOFTWARE 11.0.X - BROADBAND ACCESS CONFIGURATION GUIDE 4-1-2010 Configuration Manual

suboption contains a string with the username and domain name in the format:
username@domainname.
The Vendor-Specific suboption contains a value that includes a JUNOSe data field.
You can configure the data field to support one or both of the following values:
layer2-circuit-id (type 1) The hexadecimal representation of the layer 2
identifier in the Agent Circuit ID (suboption 1) value (for example, the ATM
VPI/VCI or Ethernet SVLAN/VLAN ID). You can configure this suboption type
without the Agent Circuit ID.
user-packet-class (type 2) The hexadecimal representation of the user packet
class field, whose value is assigned by the layer 2 policy application. The layer
2 policy application can be used to map the DHCP packet or message IEEE
802.1p value to the user packet class field. See the JUNOSe Policy Management
Configuration Guide for information about layer 2 policies.
Configuration Example—Using DHCP Relay Option 82 to Pass
IEEE 802.1p Values to DHCP Servers
Using the DHCP relay agent option 82 feature, you can configure an environment in
which a customized DHCP server assigns an IP address that provides the desired
service to the DHCP client.
The DHCP server uses information based on the IEEE 802.1p values, which are
extracted from the DHCP packets using JUNOSe software layer 2 policies, to determine
the appropriate IP address to assign to the client.
This type of environment, which is illustrated in Figure 13 on page 508, includes the
following components:
Layer 2 policy on the ingress interface (that is, the interface that receives the
client's DHCP packet) that maps the 802.1p value from the packet to a user
packet class (UPC.)
NOTE: To ensure optimal performance when mapping 802.1p values to UPCs, order
the classifier groups in the VLAN policy list with the most often used UPC values
listed first.
DHCP relay agent option 82 configuration that enables Vendor-Specific suboption
type 2 (User Packet Class) support and maps the Layer 2 policy user packet class
to the option 82 user packet class suboption.
Customized DHCP server configuration that assigns IP addresses based on the
option 82 user packet class suboption. The IP address is associated with the
appropriate quality, type, or class of service for the user packet class specified
in the option 82 suboption.
Chapter 20: Configuring DHCP Relay
Configuring DHCP Relay and BOOTP Relay
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