A cost efficient IPSec Accelerator board utilizing a crypto chip and an entry-level Linux PC for the high performance VPN is presented in this paper. The IPIP (IP-over-IP tunneling) processing, encryption & decryption processing, HASH processing, and the integrity test functions of IPSec are processed in the IPSec Accelerator board. The proposed IPSec Accelerator has demonstrated successful execution of the required functions of the IPSec packet processing and verified its performance by processing the IPSec packets at the rate of over 1 Gbps.