Which AOS-CX feature is used to prevent head-on-line (HOL) blocking?
Which AOS-CX feature is used to prevent head-on-line (HOL) blocking?
Virtual Output Queuing (VOQ) is specifically designed to prevent head-of-line (HOL) blocking. HOL blocking occurs when a packet at the front of a queue is delayed, causing all subsequent packets in the queue to be delayed as well. VOQ mitigates this by maintaining separate queues for each output port, ensuring that packets destined for non-congested ports are not held up by packets destined for congested ports. This optimizes traffic flow and maximizes performance.
Page 822 Study Guide: ArubaOS- CX switches use an intra- switch queuing method called Virtual Output Queuing (VoQ). If the ingress buffer used a single queue, head of line (HOL) blocking could delay the traffic. If the packet at the front of the queue is destined out a congested port, it delays all packets behind it, even though those that are destined to non- congested ports. VoQ prevents this problem [Aruba Networks]
Wire speed and VOQ A network is only as fast as its slowest component. Without the right performance and capacity for your wired network, the move to Wi-Fi 6 isn’t feasible. Many legacy switches suffer from head-of-line blocking, which limits the throughput of each port—costing both time and the bottom line. Look for switches that have a non-blocking architecture with virtual output queuing (VOQ) and wire speed performance. While common in data center switches, such capabilities will also be critical for campus or edge networks with high-density Wi-Fi 6 deployments in order to: Prevent head-of-line blocking by optimizing traffic flows through the switch Achieve maximum performance on every port