Key points for choosing a small knock-on Gigabit Switch

The backboard bandwidth in a Gigabit Switch mainly refers to the maximum data volume between the processor and the data bus. It should be said that it represents the comprehensive performance of the Gigabit Switch, which is one of the parameters we must carefully look at when purchasing. At present, Gigabit Ethernet has become a strategic choice for high-speed and enterprise-level broadband network applications thanks to its fast and stable advantages. Recently, my company has taken into account the increase and development trend of its employees and the need to transform and upgrade the original MB network to ensure network bandwidth, prepare to use all ge switches as the switch devices for the enterprise network, and implement Mbit/s to the desktop.

As the head of the network department, I took charge of the purchase of gigabit switch products. After a period of investigation and analysis, the author successfully completed the task and summarized some purchase precautions and common purchase mistakes.

I. Classification of GE Switches

GE switches are generally used in the backbone network of large enterprise Ethernet. They can adopt two transmission media: Optical Fiber and twisted pair wires, which correspond to SC and RJ-45 ports respectively. It has multiple categories. From the perspective of LAN design and application, gigabit switches can be divided into three categories: gigabit core switches, Gigabit working group switches, and gigabit desktop switches. Divided by the working protocol layer, gigabit switches can be divided into L2 switches, L3 switches, and L4 switches. The higher the supported protocol layer, the higher the technical performance of the switch product, the higher the grade.

2. Pay attention to the eight-point shopping

Like a common m switch, when purchasing a gigabit switch, you need to determine the performance of the switch, mainly to pay attention to the performance indicators of the switch, for example, switching mode, port type, backboard bandwidth, and network management functions. In addition, because the price of GE switches is relatively expensive, it is essential to consider the price and service.

1. Price, brand

At present, the price of gigabit switches sold in the market is extremely chaotic, such as the domestic Huaji technology visida VCT) 5280GP Gigabit Switch prices only in 1800 yuan, TP-LINKTL-SL3226P prices in 2750 ~ Between 3500 RMB. The foreign manufacturers of similar products is 5000 or 6000 yuan, tens of thousands or even hundreds of thousands of yuan, such as the price of CiscoWS-C4006-S4-DC is 100,000 yuan. Therefore, when purchasing a gigabit switch, you must pay attention to the price and be sure to compare the three. In addition, in terms of the vswitch brand, the product quality of Cisco, 3Com and other foreign manufacturers is guaranteed. Although many domestic manufacturers have also begun to produce gigabit switches, we recommend that you choose products from well-known manufacturers, such as TP-LINK, D-Link, Lenovo, and Huawei-visida.

2. exchange mode

Currently, GE switches use two main exchange modes: storage-based forwarding and direct-through forwarding. Storage-based forwarding requires that the switch decide how to forward after receiving all data packets, as one of the most widely used technologies in the computer network field, most switch products now support this technology, such as 3ComSuperStack3Switch4900 and the above mentioned switch. When purchasing a gigabit network card, pay attention to whether the storage forwarding mode is supported to ensure the normal operation of the network. Direct-through forwarding means that the switch has started to forward data before it receives the entire frame, which can reduce the latency and is rarely used at present.

3. Port type

Currently, most gigabit switches are 10/100/100/1000 Mbps adaptive ports and 10/100 Mbps adaptive ports. The above mentioned Huawei-visida 5280GP is a/Mbps adaptive Port product; 3ComSuperStack3Switch49003C17700) is a 100/1000 Mbps adaptive Port product. To sum up, there are four common combinations: a 10/100 Mbps + B 1000 Mbps, a 10/100 Mbps + B 100/1000 Mbps, a 100/1000 Mbps and a Mbps. Note: a and B indicate numbers, for example, four 10/100 Mbps + one 100/1000 Mbps ). The last product is rare and expensive. We recommend that you select the first three vswitches.

4. Board bandwidth

The backboard bandwidth is the maximum data volume that can be transferred between the vswitch interface processor and the data bus. The value directly affects the performance of the Gigabit Switch. Pay attention to the bandwidth of the backboard when purchasing a vswitch. The wider the backboard bandwidth, the better. In this way, when the port bandwidth and delay time are the same, the higher the transmission rate of the switch. Generally, the bandwidth of a Gigabit Switch is larger than 8 Gbps, including 16, 24, 32, and 48. Some high-end core products can be expanded to 720 Gbps, such as CiscoWS-C6509. Generally, there is no limit on the number of users. Generally, the larger the bandwidth, the higher the price. for small and medium-sized enterprises, we recommend that you select a bandwidth of about 32 Gbps.

5. network management functions

Through the network management function, you can use management software to manage and configure vswitches, such as Web browsers, Telnet, SNMP, and RMON. Like a common switch, the more network management functions a GE switch supports, the higher the price. When purchasing a gigabit switch, you can choose based on your needs. For core switches, you need powerful network management functions, or select a dedicated gigabit network management switch, such as SMC8612XL3.

6. VLAN support

VLAN is a virtual LAN. Through VLAN support, it can prevent the LAN from generating broadcast effects and enhance management and security between network segments. Different manufacturers of switches to VLAN support different capabilities, support VLAN number is also different, for example, CiscoWS-C6509 support 1000 VLANs, and Lenovo tiangai iSpirit3508G-L3 support 64 VLANs. Most Gigabit Switches now support port-based, IP-and MAC-based, and multicast-based VLANs.

7. MAC address count

The number of MAC addresses is the maximum number of MAC addresses that can be stored in the MAC address table of the vswitch. The more MAC addresses are supported, the higher the data forwarding rate. Generally, a Gigabit Switch can have more than 4 k MAC addresses, such as 6 k, 8 k, 16 k, and 32 k. The larger the number of supported MAC addresses, the higher the general price. We recommend that you select a Gigabit Switch with 16 k mac addresses.

8. After-sales service

Because a Gigabit Switch is different from an ordinary M switch, it has a great difference in price and technology, and the after-sales service level of the product is crucial. When purchasing a gigabit switch, we also need to compare the service level of each brand, including the three-pack service, on-site service, product maintenance, product maintenance, and cost. Considering the localization service factors, it is recommended to choose domestic manufacturers of products, such as Huawei, TP-LINK and so on. In addition, when purchasing a gigabit switch, you should also pay attention to whether the product has a layer-3 switching capability, whether it supports stacking, and whether it supports Qos/Cos.

Iii. Common purchase errors

1. Gigabit = 1000 Mbps?

When purchasing a Gigabit Switch, many network users mistakenly believe that the switch with a Mbps port is a Gigabit Switch. In fact, this is incorrect. In the current market, any port with a transmission rate of 10/100 Mbps is referred to as a Gigabit Switch. For example, most mainstream products currently provide 100/1000/Mbps adaptive and Mbps adaptive ports, port 10/100 Mbps is provided to desktop users, and port Mbps is used for core switching. In fact, there are not many products with a single Mbps port.

2. packet forwarding rate = backboard bandwidth?

Packet forwarding refers to the size of the packet forwarding capability of the switch, which is generally measured in pps. The packet forwarding rate of a Gigabit Switch generally ranges from several Mpps to dozens of Mpps, an important indicator of packet forwarding rate is the backboard bandwidth. However, the bandwidth refers to the maximum data volume of a vswitch. The wider the bandwidth, the larger the packet forwarding rate.