What is a core switch and what are the differences from a regular switch

Core switches are switches placed in the core layer, and generally large enterprise networks require the use of core switches to achieve strong network scalability and protect existing investments. A core switch is designed for network architecture. If it is a small local area network with several computers, an 8-port small switch can be called a core switch; In the network industry, core switches refer to layer 2 or layer 3 switches with network management functions and strong throughput. A core switch is essential for a network with over 100 computers to operate stably and at high speed< Br/>


1. Differences in ports



The number of ports in a regular switch is generally 24-48, with most of the network ports being Gigabit Ethernet or 100 Gigabit Ethernet. The main function is to access user data or gather switch data from the access layer. This type of switch can be configured with Vlan simple routing protocol and some simple SNMP functions at most, and the backplane bandwidth is relatively small< Br/>


There are a large number of core switch ports, which are usually modular and can be freely paired with optical ports and gigabit Ethernet ports. Generally, core switches are three-layer switches that can set various advanced network protocols such as routing protocols/ACL/QoS/load balancing. The most important point is that the backplane bandwidth of the core switch is much higher than that of a regular switch, and usually has a separate engine module, which is the main backup< Br/>


2. Differences in user connection or access to the network



The part of the network that directly faces users to connect or access the network is usually called the access layer, and the part located between the access layer and the core layer is called the distribution layer or aggregation layer. The purpose of the access layer is to allow end users to connect to the network, so the access layer switch has the characteristics of low cost and high port density. A convergence layer switch is a convergence point for multiple access layer switches, which must be able to handle all traffic from access layer devices and provide uplink to the core layer. Therefore, a convergence layer switch has higher performance, fewer interfaces, and higher switching rates< Br/>


The backbone of the network is called the core layer, whose main purpose is to provide an optimized and reliable backbone transmission structure through high-speed forwarding communication. Therefore, the core layer switch application has higher reliability, performance, and throughput< Br/>


Compared to regular switches, core switches need to have features such as large cache, high capacity, virtualization, scalability, and module redundancy technology< Br/>


3. Large cache technology



The data center switch has changed the traditional port caching method of switching systems, adopting a distributed caching architecture. The cache is much larger than ordinary switches, with a cache capacity of over 1G, while ordinary switches can only reach 2-4M. For each port, it has a burst traffic caching capacity of 200 milliseconds under full line speed of 10 Gigabit, which ensures zero packet loss for network forwarding even in the event of burst traffic. This is precisely suitable for the characteristics of large server volume and burst traffic in data centers< Br/>


4. High capacity devices



The network traffic of data centers has the characteristics of high-density application scheduling and surge buffering, while ordinary switches are mainly designed to meet the interconnection and interworking needs, and cannot achieve precise identification and control of services. In large business situations, they cannot achieve fast response and zero packet loss, and cannot guarantee business continuity. The reliability of the system mainly depends on the reliability of equipment< Br/>


So ordinary switches cannot meet the needs of data centers. Data center switches need to have high capacity forwarding characteristics. Data center switches must support high-density 10 Gigabit cards, that is, 48 port 10 Gigabit cards. To enable 48 port 10 Gigabit cards to forward at full line speed, data center switches can only use the CLOS distributed switching architecture. In addition, with the popularization of 40G and 100G, 100G cards that support 8-port 40G cards and 4-port 100G cards are gradually becoming commercially available. 40G and 100G cards in data center switches have already entered the market, meeting the demand for high-density applications in data centers< Br/>


5. Virtualization technology



The network devices in data centers need to have the characteristics of executive rationality and high security reliability, so the switches in data centers also need to support virtualization. Virtualization refers to transforming physical resources into logically manageable resources to break down barriers between physical structures. The virtualization of network devices mainly includes technologies such as multi virtual one, one virtual multiple, and multi virtual multiple< Br/>


Through virtualization technology, multiple network devices can be managed uniformly, and businesses on one device can be completely isolated, thereby reducing data center management costs by 40% and increasing IT utilization by approximately 25%< Br/>


6. Scalability



Scalability should include two aspects:



a. Number of Slots: Slots are used to install various functional modules and interface modules. Due to the fixed number of ports provided by each interface module, the number of slots fundamentally determines the number of ports that a switch can accommodate. In addition, all functional modules (such as super engine module, IP voice module, extended service module, network monitoring module, security service module, etc.) need to occupy one slotTherefore, the number of slots fundamentally determines the scalability of the switch< Br/>


b. Module Type: Undoubtedly, the more supported module types (such as LAN interface module, WAN interface module, ATM interface module, extension function module, etc.), the stronger the scalability of the switch. Just taking the LAN interface module as an example, it should include RJ-45 module, GBIC module, SFP module, 10Gbps module, etc. to meet the needs of complex environments and network applications in large and medium-sized networks< Br/>


7. Module redundancy



Redundancy capability is a guarantee for the safe operation of the network. No manufacturer can guarantee that their products will not malfunction during operation. The ability to switch quickly when a fault occurs depends on the redundancy capability of the device. For core switches, important components should have redundancy capabilities, such as management module redundancy, power redundancy, etc., in order to ensure stable network operation to the greatest extent possible< Br/>


8. Routing redundancy



Utilizing HSRP and VRRP protocols to ensure load sharing and hot backup of core devices, in the event of a failure of a switch in the core switch and dual aggregation switch, the three-layer routing device and virtual gateway can quickly switch, achieving redundant backup of dual lines and ensuring overall network stability< Br/>


Seten, a trusted server hardware and solution provider in the global digital processUsing&quo; Spot+Agency&# quo; Model, rapid response, specialized management, and professional and efficient services to assist partners in achieving digital upgrades and winning the new data era. Saitern has three main product lines: Samsung SSD, Memory (RDIMM), SOLIDIGM SSD, and Broadcom network products. It is also an agent for NVIDIA's Melosi network products and the complete XFusion server.