3Com 5500 SI - Switch - Stackable, Configuration Manual

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284 C
HAPTER
17: N
ETWORK
P
ROTOCOL
O
PERATION
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Len: Specifies the Length of the agent information field.
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Agent information field: Specifies the sub-options used.
2 Sub-option format
Figure 68 illustrates the sub-option format.
Figure 68 Sub-option format
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SubOpt: Sub-option number. Currently, the value of this sub-field can be 1, 2, and
5, which have the following meanings:
1 represents this sub-option is for agent circuit ID (Circuit ID);
2 represents this sub-option is for remote agent ID (Remote ID);
5 represents this sub-option is for link selection.
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Len: Length of the Sub-option value sub-filed.
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Sub-option value: Value of the sub-option. For example, the value for sub-option 1
is Circuit ID.
3 Related specification
The following are the RFCs concerning option 82 supporting.
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RFC2131 Dynamic Host Configuration Protocol
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RFC3046 DHCP Relay Agent Information Option