IP Configuration
IPv4 Management and Interfaces
284 Cisco Small Business 200, 300 and 500 Series Managed Switch Administration Guide (Internal Version)
17
The following describes how DHCP Reply packets are handled when DHCP
Snooping is disabled:
Option 82
Insertion
Enabled
Relay – is sent
with Option 82
Bridge – Option
82 is added
(if port is
trusted,
behaves as if
DHCP Snooping
is not enabled)
Packet is
sent with the
original
Option 82
Relay – is sent
with Option 82
Bridge –
Option 82 is
inserted
(if port is
trusted,
behaves as if
DHCP
Snooping is
not enabled)
Relay –
discards the
packet
Bridge –
Packet is sent
with the
original
Option 82
DHCP Relay
VLAN with IP Address
DHCP Relay
VLAN without IP Address
Packet arrives
without
Option 82
Packet arrives
with Option
82
Packet arrives
without
Option 82
Packet arrives
with Option
82
DHCP Relay
VLAN with IP Address
DHCP Relay
VLAN without IP Address