Because LAN switches use virtual circuit switching, they can technically ensure that the bandwidth among all input and output ports is non-contentious, enabling high-speed data transmission between ports without creating transmission bottlenecks. This greatly increases the data throughput of network information points and optimizes the overall network system. This article explains the five main technologies involved.
1. Programmable ASIC (Application-Specific Integrated Circuit)
This is a dedicated integrated circuit chip specifically designed to optimize Layer-2 switching. It is the core integration technology used in today’s networking solutions. Multiple functions can be integrated onto a single chip, offering advantages such as simple design, high reliability, low power consumption, higher performance, and lower cost. Programmable ASIC chips widely adopted in LAN switches can be customized by manufacturers—or even by users—to meet application needs. They have become one of the key technologies in LAN switch applications.
2. Distributed Pipeline
With distributed pipelining, multiple distributed forwarding engines can rapidly and independently forward their respective packets. In a single pipeline, multiple ASIC chips can process several frames simultaneously. This concurrency and pipelining elevate forwarding performance to a new level, achieving line-rate performance for unicast, broadcast, and multicast traffic on all ports. Therefore, distributed pipelining is an important factor in improving LAN switching speeds.
3. Dynamically Scalable Memory
For advanced LAN switching products, high performance and high-quality functionality often rely on an intelligent memory system. Dynamically scalable memory technology allows a switch to expand memory capacity on the fly according to traffic requirements. In Layer-3 switches, part of the memory is directly associated with the forwarding engine, enabling the addition of more interface modules. As the number of forwarding engines increases, the associated memory expands accordingly. Through pipeline-based ASIC processing, buffers can be dynamically constructed to increase memory utilization and prevent packet loss during large bursts of data.
4. Advanced Queue Mechanisms
No matter how powerful a network device is, it will still suffer from congestion in the connected network segments. Traditionally, traffic on a port is stored in a single output queue, processed strictly in FIFO order regardless of priority. When the queue is full, excess packets are dropped; when the queue lengthens, delay increases. This traditional queuing mechanism creates difficulties for real-time and multimedia applications.
Hence, many vendors have developed advanced queuing technologies to support differentiated services on Ethernet segments, while controlling delay and jitter. These can include multiple levels of queues per port, enabling better differentiation of traffic levels. Multimedia and real-time data packets are placed in high-priority queues, and with weighted fair queuing, these queues are processed more frequently—without completely ignoring lower-priority traffic. Traditional application users do not notice changes in response time or throughput, while users running time-critical applications receive timely responses.
5. Automatic Traffic Classification
In network transmission, some data flows are more important than others. Layer-3 LAN switches have begun adopting automatic traffic classification technology to distinguish between different types and priorities of traffic. Practice shows that with automatic classification, switches can instruct the packet-processing pipeline to differentiate user-designated flows, achieving low latency and high-priority forwarding. This not only provides effective control and management for special traffic streams, but also helps prevent network congestion.
Post time: Nov-20-2025