Handy tool: DHCP Option 43 builder

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  • Idea
  • Updated 3 years ago

Author says: "You're welcome to use; Disclaimer: Not really debugged, I take no responsibility for errors or for the availability of the service in the future;"

but if you've ever struggled with all the hex...you'll appreciate it!
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Keith - Pack Leader

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Posted 6 years ago

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It would be nice to know what calculation method is being used by Ruckus so that if this site is down/unavailable we can do it ourselves.
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Tim Morton

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It is the vendor controller identifier and HEX value of the IP address.
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Abilash P R, Employee

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Hi Ali,

DHCP Option 43 for ZD and vSZ can be calculated as below.

Let us assume is the IP address of ZD/vSZ/SZ, the formula would be.

Sub option (ZD:03) or (vSZ:06) + Length of the IP in HEX HEX Value of the IP (ASCII to HEX).

Lets apply above formula on IP

Sub Option ZD = 03

Length of IP in HEX has a length of 11 or hex value of 0x0b = 0b

Example string length for different IP: has a length of 10 or hex value of 0x0a has a length of 11 or hex value of 0x0b has a length of 11 or hex value of 0x0b has a length of 12 or a hex value of 0x0c has a length of 14 or a hex value of 0x0e

Hex Value of IP

ASCII to HEX of '1' = 31
ASCII to HEX of '0' = 30
ASCII to HEX of '.'  = 2E
31302e 31302e 31302e 3130

The Complete Option 43 Hex for IP with ZD sub option (03) is  030b31302e31302e31302e3130

The Complete Option 43 Hex for IP with vSZ sub option (06) is 

This is the coverstion method, Hope this Helps.

Abilash PR.