A Security Association (SA) lookup table is maintained at a network interface. The SA data is stored in a memory external to the network interface, for example, in the memory of a host electronic system in which the network interface provides network access. The lookup table stores sufficient information for the network interface, or another system component, to access the SA data. When a cryptography operation is to be performed, the SA data is retrieved from the external memory and delivered to the processor performing the cryptographic operations. In one embodiment, destination Internet Protocol (IP) address and the IPSec protocol are checked after the SA data is retrieved from the external memory. In one embodiment, the lookup table entries contain only an offset value from a base address value to locate the SA data.