Difference among Core switch, Distribution Switch and Access Switch

For building a network, the first step is planning and design, and the current network design is a hierarchical design. For example, an ordinary home is a first-tier network design. A little more equipment requires a second-tier network world, and a larger scale requires a second-tier network world. Three-layer design, such a hierarchical design and construction, can make the entire network simpler, save costs and reduce faults, and have more flexible scalability.

The so-called core switch, Distribution switch and access switch, among which the core switch and the Distribution switch are the concept of three-layer network design, which refers to the level of the switch. 3 Layer switch, the Distribution switch is at layer 2, and the first layer is a common switch or access switch. It is conceivable that for ordinary switches or access switches belonging to the first layer, they are mainly faced with terminals such as computers, so there are a large number of interfaces, and the performance requirements are not particularly high. After that, these access switches are aggregated into fewer lines and connected to the Distribution switches. At this time, the access switches collect all terminal data and hand them over to the Distribution switches. Then the performance of the Distribution switches is much stronger than that of the access switches. .

Features and Functions of Access Layer Switches

We usually refer to the part of the network that directly connects or accesses the network to users as the access layer, which is equivalent to the grassroots employees in the company structure.

The access layer provides users with the ability to access the application system on the local network segment, mainly solves the mutual access requirements between adjacent users, and provides sufficient bandwidth for these accesses. In large and medium-sized networks, the access layer should also be properly responsible for some user management functions (such as address authentication, user authentication, billing management, etc.), and user information collection (such as user IP addresses, MAC addresses, access logs, etc.) .

Because the primary purpose of the access layer is to allow end users to connect to the network, access layer switches tend to have low cost and high port density, and cost-effective devices are often recommended. Both managed and unmanaged switches can be used at the access layer, depending on the specific budget and network needs.

Features and Functions of Distribution Layer Switches

It is not difficult to understand that the Distribution layer is also equivalent to the middle-level management of the company. It is used to connect the core layer and the access layer. It is in the middle position. Its uplink is the core switch, and the downlink is the access layer switch.

The convergence layer has various functions such as policy enforcement, security, workgroup access, routing between virtual local area networks (VLANs), source or destination address filtering, and it is where policies are implemented.

Because the Distribution layer switch is the aggregation point of multiple access layer switches, it must be able to handle all traffic from the access layer devices and provide the uplink to the core layer, so the Distribution layer switch is compared with the access layer switch. Higher performance and switching speeds and fewer interfaces are required.

In practical applications, the Distribution layer is often omitted. When the transmission distance is short and the core layer has enough accesses to directly connect to the access layer, the Distribution layer can be omitted. This is a common practice. First, it can save the overall cost, and secondly, it can reduce the Maintenance burden, network conditions are also easier to monitor.

Features and Functions of Core Layer Switches

The core layer is the backbone of the network and guarantees the performance of the entire network. Its equipment includes routers, firewalls, core layer switches, etc., which are equivalent to the top management in the company structure.

The main purpose of the core layer switch is to provide a fast and reliable backbone transmission structure through high-speed forwarding of communication. Therefore, the core layer switch should have the following characteristics: reliability, high efficiency, redundancy, fault tolerance, manageability, adaptability, Low latency, etc.

Because the core layer is the pivotal center of the network and its importance is prominent, the core layer switches should adopt gigabit or even 10G managed switches with higher bandwidth, higher reliability, higher performance and throughput. 3 Layer  switches that exchange based on IP addresses and protocols are generally used at the core layer of the network, and are also used in a small amount at the Distribution layer. Some 3 Layer switches also have Layer 4 switching functions, which can judge the target port according to the protocol port information of the data frame.