RADIUS AAA High Availability and Efficient Load Distribution for Performance and Scalability

RADIUS service continuity requires the ability to process a large number of AAA requests across a limited number of static broadband remote access server (BRAS) clients and a small number of RADIUS proxies. RADIUS authentication is a critical component of broadband access and any RADIUS service failure immediately translates into subscriber retention problems and increased churn.

• RADIUS availability – RADIUS employs the user datagram protocol (UDP). Typically, a large number of AAA requests are received across a single UDP port, making it impossible to effectively distribute the RADIUS request load based on Layer 4 UDP session source and destination information alone. RADIUS service continuity requires the ability to perform intelligent Layer 7 transaction persistency and load distribution to meet a large number of AAA requests from across a limited number of BRAS clients and RADIUS proxies

• RADIUS scalability and traffic surge control – RADIUS service is negatively impacted by traffic bursts caused by BRAS failures, resulting in a sudden peak of high volume user re-connection attempts. This requires the ability to transparently distribute and scale RADIUS service requests to meet surges
  
  
• RADIUS service integrity – RADIUS servers are susceptible to malicious UDP floods, requiring protection against implicit network attacks that can cause Denial of Service (DoS) for AAA processing