What is a DIP IP shift?

A.
When specific addresses in the DIP pool require port translation and others do not

B.
When a one-to-one mapping of a range of internal addresses to a range of external addresses is needed

C.
When a DIP has run out of addresses in the DIP pool and must "shift" to addresses from another pool instead

D.
When a DIP pool is "shifted" to use an address pool in the network range of the secondary address instead of the primary address

Explanation:
You can define a one-to-one mapping from an original source IP address to a translated source IP address for a
range of IP addresses. Such a mapping ensures that the NetScreen device always translates a particular source IP address from within that range to the same translated address within a DIP pool. There can be any number of addresses in the range. You can even map one subnet to another subnet, with a consistent one-to-one mapping of each original address in one subnet to its translated counterpart in the other subnet.