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What is the significance of the type length value (TLV) block values with respect to DHCP option 43? How is the TLV value calculated?

April 26, 2017block DHCP LENGTH option respect significance tlv type value values

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What is the significance of the type length value (TLV) block values with respect to DHCP option 43? How is the TLV value calculated?

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A. DHCP option 43 can be enabled on the DHCP server of the Cisco IOS router using this command: Option 43 hex The hexadecimal string in this command is assembled by concatenating the TLV values for the option 43 sub-option. Type + Length + Value • Type is always the sub-option code 0xf1. • Length is the number of controller management IP addresses times 4 in hex. • Value is the IP address of the controller listed sequentially in hex. For example, assume that there are two controllers with management interface IP addresses 10.126.126.2 and 10.127.127.2: • The type is 0xf1. • The length is 2 * 4 = 8 = 0x08. • The IP addresses translate to 0a7e7e02 (10.126.126.2) and 0a7f7f02 (10.127.127.2). • Assembling the string then yields f1080a7e7e020a7f7f02.