User guide

Security
1/1551-HSC 901 35/3 Uen C 2005-12-02
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Figure 57 DHCP Request with Relay Agent (Option 82)
The Service Provider receives the DHCP request in the DHCP server and
(based on the Option 82 identifier) authenticates the DHCP request. The
DHCP server can then assign an IP address to the end-user according to
the services offered by the ISP.
The EDA solution offers three different identification options to be used
when DHCP Option 82 is enabled:
• String option - A string of up to 253 octets can be inserted
• Cisco option - A format specified by Cisco.
• Customer Number Format - A format specified automatically by PEM.
If the String Option 82-identifier option is selected a binary string of up to
253 octets will be inserted as sub-option 2 (Agent Remote ID).
The String Option complies with RFC 3046.
If the Cisco Option 82 identifier option is selected, the option 82 will be
encoded in a Routed Bridge Encapsulation (RBE) format specified by
Cisco.