Subscriber-Aware Load Balancing

Subscriber-Aware Load Balancing (SALB) is a technique used in telecom and mobile core networks (such as EPC, 5G Core, or DPI-based systems) to distribute user traffic intelligently.

Enhanced Subscriber Intelligence: The load balancing feature significantly enhances the ASN node's capability in enabling subscriber-level intelligence. It achieves this by egressing correlated control and user plane traffic to probes for in-depth analysis.

Efficient Load Distribution: This feature ensures efficient distribution of network load across multiple tools. By balancing the traffic, it prevents any single tool from becoming overwhelmed, thereby maintaining optimal network performance.

Comprehensive Network Analysis: The load balancing feature is crucial for achieving comprehensive network analysis. By directing correlated traffic to specific probes, it allows for detailed monitoring and assessment of traffic pattern.

Currently, wo subscriber-aware load balancing options are available, which can be configured based on customer requirements:

1. Subscriber aware load balancing based on IMSI

2. Subscriber aware load balancing in round-robin fashion

Hash based LB:

The IMSI is used to compute a hash value based on the number of probes in the core network. The hash function takes the modulo of the IMSI with the tool count, yielding a value between 0 and the tool count. This hash value is established when the first request packet of a subscriber flow is received. Using correlation logic, all subsequent control and user packets for the same subscriber are directed to the same tool, ensuring consistent and efficient traffic analysis.

Round Robin LB:

Alternatively, the ASN node can use round-robin load balancing, assigning flows to tools sequentially to evenly distribute the load, regardless of IMSI. A hash table maintains the tool ID for each subscriber, ensuring all packets from the same subscriber go to the same tool. This method effectively balances the network load, especially for large traffic flows.