# DHCP Option 43

• Question
• Updated 3 years ago
So Ruckus suggests using the shimi.net website for Ruckus DHCP Option 43.  However I would instead like to know what method is being used to calculate the DHCP Option 43 value for Ruckus.  Cisco explains it on their website for their WLC's.  Why can't Ruckus do the same?

What if that site is down or what if there is an issue with it, I would much rather know what is Ruckus using to calculate the values.

Thanks
• 36 Posts

Posted 3 years ago

• 14 Posts
If you are using a Windows DHCP server or have access to one, you can put in the IP address of the ZoneDirector on the far left side and that will automatically put in the Binary and Data values. You should be able to take the Binary info and move it to any needed DHCP server to fulfill the option requirement.
• 14 Posts
I should have added the following:

It is the vendor controller identifier and HEX value of the IP address.

Abilash P R, Employee

• 60 Posts
Hi Ali,

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

Let us assume 10.10.10.10 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 10.10.10.10

Sub Option ZD = 03

Length of IP in HEX

10.10.10.10 has a length of 11 or hex value of 0x0b = 0b

Example string length for different IP:

10.9.52.32 has a length of 10 or hex value of 0x0a
10.10.52.32 has a length of 11 or hex value of 0x0b
10.11.52.32 has a length of 11 or hex value of 0x0b
10.111.52.32 has a length of 12 or a hex value of 0x0c
192.168.100.10 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

10.10.10.10
31302e 31302e 31302e 3130

The Complete Option 43 Hex for IP 10.10.10.10 with ZD sub option (03) is  030b31302e31302e31302e3130

The Complete Option 43 Hex for IP 10.10.10.10 with vSZ sub option (06) is
060b31302e31302e31302e3130

This is conversion method used, Hope this Helps.

Regards,
Abilash PR.
(Edited)
• 36 Posts