Restrict extensions calls to extensions

hi im trying to restrict the calls between my extensions
i have 2 ranges
range 100-199 are administration
range 200-299 are marketing
i dont want communication between themwith the exception of the ceo and marketing boss ext 110,102 they can call every body for example not in the other way
how can i do this thing??? please helpme

FreePBX is not inherently “multi-tenent”, asterisk allows communication between endpoints dependent on the context of each endpoint and what is “included” in such contexts, with some effort you can use the “custom contexts” module to define such restrictions, but it is not easy and you will have to fully understand the way contexts work.