Authorization Issue with navigational attribute..

Dear Experts,

I am stuck with Navigational attribute authorization.

I have created a custom master Info object ZSPOKE.

Now this has 2 navigational attribute ZZONE and ZHUB.

I have checked all the authorization related settings but still this not working.

ZONE HUB SPOKE

Delhi Delhi Delhi

Delhi Delhi Mayapuri

Delhi Gurgaon Faridabad

Delhi Gurgaon Ghaziabad

Delhi Jaipur Bhilwara

Delhi Jaipur Kota

The above mentioned is the example of the Zone - Hub - Spoke levels.

I need to authorize user based on HUB or Spoke or even on Zone level.

Please advice.

Thanks,

Sanjana.