According to industry analysts, fewer than 20% of mission critical Internet applications achieve internal objectives for continuous availability.  Challenges include maintaining uptime when servers fail, scaling data center capabilities to handle increased load, and protecting infrastructure from network vulnerabilities. For applications requiring persistence, the Barracuda Load Balancer can maintain state using client IP addresses or Layer 7 information such as client cookie, depending on model. It can also be used to provide Global Server Load Balancing (GSLB) for multi-site redundancy.