{"id":5980,"date":"2023-01-16T14:53:36","date_gmt":"2023-01-16T13:53:36","guid":{"rendered":"https:\/\/www.excentis.com\/blog\/\/"},"modified":"2023-07-06T14:46:58","modified_gmt":"2023-07-06T13:46:58","slug":"active-queue-management-aqm-the-key-to-reducing-latency","status":"publish","type":"post","link":"https:\/\/www.excentis.com\/blog\/active-queue-management-aqm-the-key-to-reducing-latency\/","title":{"rendered":"Active Queue Management (AQM): the key to reducing latency\u00a0"},"content":{"rendered":"

\"AQM<\/p>\n

The battle for network speed and capacity is on<\/strong> in home networks. For smooth videoconferencing and online gaming services, low latency is key. Streaming and download services require high bandwidth. All that competition for speed and capacity puts your network quality under serious pressure<\/strong>. Active Queue Management (AQM) to the rescue!<\/p>\n

The basics: buffers and queues\u00a0<\/strong><\/h2>\n

To understand what Active Queue Management is about, we must start with memory buffers and queues. Most modern network devices<\/strong> like routers and switches come with a set of queues, which all have<\/strong> a buffer to store arriving packets<\/strong>. The queues absorb naturally occurring bursts of traffic: when there is too much traffic, it is temporarily held back in the buffer to avoid unnecessary losses.<\/p>\n

However, when<\/strong> high-speed (often TCP-based) applications put too much pressure<\/strong> on the network, these<\/strong> will start to fill up and block real-time data in the queues<\/strong>. The result: high delay and possibly varying packet delays, also known as latency and jitter. This will severely degrade interactive applications or even break them completely (\u2018buffer bloat\u2019).<\/p>\n

\u2192 Deeper dive into latency? Read our low latency blog post series.<\/a><\/p>\n

Why embrace Active Queue Management?<\/h2>\n

Queues used to operate on the principle of tail drop: a packet was put in the queue only if there was still enough space, if not, the packet was dropped<\/strong>.<\/p>\n

Active Queue Management (AQM) is smarter<\/strong>: it actively marks or drops packets before the queue is full<\/strong>, usually by maintaining mark\/drop probabilities<\/strong>. In this way, AQM:<\/p>\n