Load Balancing Algorithms & Modes

In Q-Balancer a DPS (Dynamic Path Selection) is an object that consists of selected WAN links and load balancing algorithm; optionally, you may set a backup DPS object to prevent network disruption in case all selected WAN links fail. The load balancing algorithm decides how a Q-Balancer appliance distributes traffic across the selected paths. In case all selected WAN links fail, the pre-defined backup DPS will be activated and take over the task automatically. Here we will illustrate how the algorithms work as follows:

> Connections distribution by real-time total bandwidth
Bi-directional Sensitive Weighted Least Traffic (BSWLT) measures total bandwidth (downlink and uplink) over the last mile, and dynamically direct new connections to the link, which has most available bandwidth.

> Connections distribution by real-time uplink bandwidth
Uplink Sensitive Weighted Least Traffic (USWLT) measures uplink bandwidth over the last mile, and dynamically direct new connections to the link, which has most available uplink bandwidth.

 

> Connections distribution by real-time downlink bandwidth
Downlink Sensitive Weighted Least Traffic (DSWLT) measures downlink bandwidth over the last mile, and dynamically direct new connections to the link, which has most available downlink bandwidth.

> Connections distribution by least response time
ISP Response Time keeps gauging the response time from target IP to the Q-Balancer appliance itself, and dynamically direct new connections to the WAN link, which has least response time.


> Connections distribution based on measured result of total bandwidth, response time, and packet loss
Optimum Routing Path keeps gauging the total bandwidth(uplink and downlink), packet loss, and response time (from target IP to the Q-Balancer appliance). It directs new connections to the path, which has best combination result of available bandwidth and least response time and packet loss.

> Connections distribution by link priority and failover
Priority always directs new connections the primary link, which has highest priority. It directs new connections to the secondary path with lower priority only when the primary link fails. The algorithm consists of several levels of priority for users to choose.

> Connections redirection to local servers based on policy rules
Redirect to Transparent Proxy redirects connection to transparent proxy by policy. This algorithm is useful for the networks with proxy servers hosted locally.

> Connections distribution by link weight
Weighted Round-Robin by Connection directs new connections to the selected WAN links in accordance with the weight, which is assigned to each of the WAN links respectively.

> Connections distribution by IP with sessions persistent
Weighted Round-Robin IP Persistent distributes traffic based on the source IP address. It directs traffic to the selected WAN links in accordance with the weight, which is assigned to each of the WAN links respectively. Meanwhile, the algorithm persists session traffic on the same path in a period of time.

> Packet-level WAN/VPN Bonding:
XBond algorithm dynamically distributes traffic by packet across multiple tunnels. The algorithm logically combines bandwidth for multiple tunnels, and the combined bandwidth theoretically equals to the sum of all the individual connections. For example, 3 * 1Mbps internet lines would provide 3Mbps of total bandwidth.

Top Benefits

  • Increased network performance

  • Minimal downtime with WAN redundancy

  • Increased WAN scalability

  • Improved productivity

  • Cost saving by leveraging low-cost broadband technologies