Network bandwidth is growing at an unprecedented speed, and the effective capture and filtering helps to boost network device performance and reducing the cost of ownership. Among these, the load balancing is one of the essential and fundamental components of packet broker’s functionalities.  It enables the device to distribute the input traffic to the output ports in a balanced way, using Balancing Groups and a Session Oriented Hash Algorithm, and, in some specific cases, use an evenly distributed approach, such as Round Robin.

When data is transmitted and the traffic flow is unevenly distributed on the instances, load balancing is necessary. Each Balancing Group is a logical association between a set of IN ports and a set of OUT ports. The traffic coming from the input ports within the same group will be balanced before being forwarded to the output groups. Every port (IN, OUT or IN/OUT) can be used to build the Balancing Groups, whereas an output port can only belong to one of these groups. All ports can also be used in other configurations without balancing.

Session-based/Flow-aware Load balancing is performed using ‘flow association’. The system maintains the association of packets with each flow or conversation between any two network endpoints, as one flow and one server. The Load Balancer will store the association between a given flow label value and a given server, which will improve the consistency and balance for all traffic from a given flow. Different flows are distributed to different ports within the group, effectively balancing the traffic across all ports of the load balanced group. Flow association is done by examining selected fields within each packet and performing a mathematical algorithm called Hashing.

The Hashing algorithm employing simple Hash mode is used to calculate the “output port” used in the balancing groups. The Hashing function is session oriented, and consists of various header parameters including L2 MAC address, L3 IPv4 Address, L4Port UDP/TCP, and so on. The algorithm guarantees that all the input traffic belonging to a specific session is sent to the same output port and thereby to the same probe, therefore is able to identify that the parameters (L2 MAC address, L3 IPv4 Address, L4Port UDP/TCP etc.) used to identify the “sessions” are also used in the hash algorithm.

Therefore, it would be pivotal and effective for a packet broker to have Load Balancing feature built in. Traffic distributed across multiple monitor ports, can effectively utilize the bandwidth of the load balanced ports. By configuring the output groups to evenly distribute traffic throughout the load balanced group, up to eight ports can be configured as a single logical pipe in any given conversation for data stream between any two points within. Moreover, the consistency of the conversation is guaranteed within the same output port, ensuring the packet monitoring tools can effectively see every single packet of a given conversation.

Luxar Tech Inc. Luxcope™ series of products address various needs in network visibility. Luxar Tech takes pride in leading the industry in cost-effectiveness and meeting customization needs. Luxcope™ LTV8134 is capable of copying, filtering, aggregating, and distributing network traffic to enable efficient use of traffic analysis tools, providing full function up to 7 tuples involved hashing load balancing: LTV8134 can receive mirrored traffic from a subset of 10GE/40GE ports, filter the received traffic by ACL rules, load-balance and redistribute the received traffic to another subset of 10GE/40GE ports for processing by traffic analysis tools so that the traffic analysis tools receive interested traffic only.

You may easily download the datasheet of LTV8134 here. should you have any questions please contact us. Additionally, we will be more than happy to schedule a live demo for you.  Please call Luxar today at 855-50-LUXAR to talk to us. We look forward to working with you!

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