In modern computer networks, core switches and ordinary switches are two key network devices, which have significant differences in network architecture and functionality. Understanding these differences and the importance of core switches is critical to building an efficient and reliable network.
The network architecture can usually be divided into three layers: the access layer, the distribution (or aggregation) layer, and the core layer. The access layer is the part of the network that directly connects to or accesses the users, and its main goal is to allow end users to connect to the network. Therefore, access layer switches are usually characterised by low cost and high port density.
The distribution layer (or aggregation layer) is located between the access layer and the core layer and serves as an aggregation point connecting multiple access layer devices. Distribution layer switches must be able to handle all traffic from access layer devices and provide uplinks to the core layer. Distribution layer switches require higher performance, fewer interfaces, and higher transfer rates than access layer switches.
The core layer is the backbone of the network and its main task is to provide an optimised and reliable backbone transmission structure through high-speed forwarding.
Therefore, core layer switches need to have higher reliability, performance and throughput in applications. The core layer is designed to meet the need for fast transmission of large amounts of data in the network and to ensure that the entire network operates in an efficient and reliable manner.
In terms of location and role, the core switch is located in the core part of the network, connecting multiple low-level switches and routers, and is responsible for handling a large amount of data traffic and realising fast connection of different network subnets. Ordinary switches are usually located at the edge or access part of the network, connecting end devices and mainly responsible for forwarding packets in the local network.
In terms of size and capacity, core switches have a higher port density and greater switching capacity to handle the high traffic demands of large networks. Ordinary switches, on the other hand, have fewer ports and are suitable for smaller networks that don't need to handle large-scale data flows like core switches.
In terms of speed and performance, core switches typically support higher data transfer speeds, such as Gigabit or 10 Gigabit Ethernet, to cope with high-speed data streams in complex networks. Ordinary switches typically support lower speeds, such as 100 Gigabit Ethernet, for basic communication between end devices.
Core layer switches are Layer 2 or Layer 3 switches with network management functions and powerful throughput. For networks with more than 100 computers, a core switch is required for stable and high-speed operation. When the network size is small, about 50 devices or less, a core switch is usually not necessary, and a router is sufficient to meet the demand.
Connecting Data Centres: Core switches play a key role in data centre networks by connecting individual servers, storage devices and other network equipment to achieve efficient communication within the data centre.
Data Forwarding: The core switch is responsible for fast forwarding of packets in the core part of the network. It connects multiple lower-level switches, routers, and other network devices, forwarding packets from one network subnet to another over a high-speed channel to achieve connectivity between the various parts of the network.
Handling large amounts of traffic: Core switches typically have high performance and high bandwidth and are capable of handling large amounts of data traffic. In scenarios such as large enterprise networks or data centers, there are many end-device communications that need to pass through the core switch, so its performance is critical.
Provides a network aggregation point: Core switches are often the aggregation point of the network, bringing together traffic from different subnets. This helps simplify the network topology and reduces the need to manage and configure network devices.
Support for high-speed connections: Core switches typically support high-speed connections, such as Gigabit or 10 Gigabit Ethernet. This allows them to handle large volumes of data traffic and adapt to rapidly evolving network requirements.
Provide network security and management features: Some core switches provide advanced network security and management features, including virtual local area network (VLAN) support, traffic monitoring, load balancing, and more. This helps ensure network security and effective management.
Achieving Redundancy and High Availability: To improve network reliability, core switches are often designed with redundancy features to prevent a single point of failure. This can be achieved through the use of redundant power supplies, redundant hardware components, or other redundant designs.
In a nutshell, core switches connect different network subnets, provide support for the rapid transmission of data across the network, and offer a range of performance, security and management features to ensure the efficient operation of the entire network. When building and maintaining a network, understanding the difference between core switches and ordinary switches as well as the importance of core switches can help to reasonably plan the network architecture, improve network performance and reliability, and meet the needs of networks of different sizes.