The VPN 3060 Concentrator can contain up to four SEP (Scalable Encryption Processing) modules for maximum system throughput and redundancy. Two SEP modules provide maximum throughput; additional modules provide redundancy in case of module failure. SEP redundancy requires no configuration: it is always enabled and completely automatic; no administrator action is required. If a SEP module fails, the VPN Concentrator automatically switches active sessions to another SEP module.This package also includes second power supply.