The State of the Art in Intrusion Prevention and Detection

192 The State of the Art in Intrusion Prevention and Detection

′

k

i

and K′: k

i

and K after being encrypted, respectively.

E

ii

(,)kkκ=

′

where E is some symmetric-

key cryptographic function

l

i

: The encrypted locations of

′

k

i

in δ

R: Proximity ranking function. Inputs documents, keywords, and locations and returns a

ranking for each document

τ: Encrypted keyword truncation index used to map the encrypted truncated keyword with its

full counterpart

β: Number of bits used to store each of the encrypted keywords

8.3.3 indexing

In our model, prior to searching for an individual document δ, the trusted client-side server must gen-

erate an encrypted index ...