Clever speed limit ensures enterprises' Internet access speed

Mr. Wang is a network administrator of an Organization. The Organization recently rented a 10 MB broadband Fiber line from the local telecommunications department, enabling the organization's LAN to directly connect to the Internet. At the beginning, no matter which workstation on the LAN accesses the webpage content or downloads information, the speed is very fast. However, with the gradual expansion of the Unit scale, the number of workstations in various departments is increasing. In addition, some unconscious employees can use professional tools such as BT to download movie or video information during work, which slows down the Internet access speed of the LAN, it may often take several minutes to open a simple web page. The organization leader attaches great importance to this phenomenon and asks Mr. Wang, who is a network administrator, to quickly take measures to solve the problem of slow local network access speed.

　　Solution Selection

Generally, there are only two main ways to increase the access speed of the broadband network. One is to increase the bandwidth at the LAN egress so that the Internet access channel can meet the work access needs of larger traffic, another way is to keep the size of the existing network bandwidth, starting from the internal optimization settings of the LAN network, to improve the outbound access efficiency of the network. Because the Unit must pay higher communication fees to increase the capacity of the egress bandwidth, it is obvious that this method has little practical significance. Therefore, Mr. Smith decided to adopt the second solution, to make appropriate optimization settings for the LAN. Considering the decrease in the speed of LAN access, this is mainly because employees do not consciously use professional tools such as BT to download large volumes of information, and P2P download applications are often difficult to directly restrict and block, as a result, Mr. Wang, a network administrator, searched for relevant information on the Internet and decided to restrict the bandwidth of each Workstation user in the LAN, to ensure that the egress Bandwidth Resources of the LAN are not exhausted.

Under normal circumstances, when we limit the Internet bandwidth of the LAN workstation, we can have two options: one is to install a professional network management tool-Sygate, with the help of this professional tool, we can limit or limit the maximum transmission speed of different subnets in the LAN, or set the speed limit for workstations with specific IP addresses; another option is to directly limit the transmission speed of a specific switch port in a manageable switch. Considering that the workstations in the LAN are scattered and installed in different locations in different departments, Mr. Smith believes that if he directly configures a proxy server to limit the bandwidth of the workstations, the cost is not only high, in addition, when all workstations in the LAN use proxy servers for Internet access, the proxy server will face a lot of traffic pressure, making it difficult for the local area network to have a substantial speed change. After repeated consideration, mr. Wang, a network administrator, decided to use the management function of the LAN switch to limit the speed of the port connecting the switch, so as to limit the unauthorized use of the BT tool to consume Internet bandwidth resources.

　　Solution implementation

After repeated consideration, after selecting a specific implementation scheme, the network administrator Mr. Wang decided to set a limit on the speed of LAN access. Because Mr. Smith has a network topology of the LAN, he quickly figured out which Subnet or workstation in the LAN by carefully comparing the drawings, corresponds to the switch port in the core switch of the organization. After finding the target, Mr. Smith immediately uses the system administrator privilege to go To the backend management interface of the switch, the bandwidth Command provided by the switch system is used to limit the maximum transmission speed of each switch port. For example, if a workstation A in the LAN is connected to Port 2 of the switch, we want the maximum transmission speed of Port 2 of the switch to be limited to less than 2 MB. To achieve this speed limit, we can first enter the vswitch background management interface as a system administrator, then enter the configuration mode of Port 2, and enter the string command "Bandwidth 2000" under the command line in this status ", after you click the Enter key, the maximum transmission speed of Port 2 of the vswitch is limited to less than 2 MB. Therefore, the maximum access speed of workstation a connected to the port will not exceed 2 MB. Note that the unit of "2000" is kb, and the unit of KB is actually 2 MB. In the same way, we can limit the connection speed of other subnets in the LAN or the Internet access speed of other workstations, as a result, the bandwidth resources at the egress of the LAN of the entire Organization will not be "occupied" by a subnet or a workstation, so the speed of the LAN access will be guaranteed.

When the number of workstations is not large, you can set the switch ports one by one to quickly limit the speed at which the workstation accesses the Internet. However, with the gradual expansion of the local area network, if we still set a single switch port in sequence, the network administrator will have a huge workload, in addition, it is not conducive to improving the efficiency of lan network maintenance. considering this, the network administrator Mr. Wang decided to divide all workstations in the same department into the same virtual subnet, in this way, the workstations of different departments are basically located in different virtual subnets, and then Mr. Smith imposes a speed limit on the switch ports connected to the virtual subnet. For example, if we want the maximum transmission speed of the virtual subnet 1 to be 2 MB, we only need to enter the vswitch background management interface as a system administrator, then enter the configuration mode of the virtual subnet 1, enter the string command "Bandwidth 2000" under the command line in this status, and click the Enter key, the maximum transmission speed of the port connecting to vsubnet 1 in the vswitch is limited to less than 2 MB, so the maximum speed of access to the Internet by All workstations in vsubnet 1 is no more than 2 MB.

　　Solution comment

By limiting the speed of the vswitch ports connected to the virtual subnet or workstation, we can easily limit the outbound speed of the LAN of the entire unit, this ensures that limited bandwidth resources will not be consumed by very few users. This speed limit solution does not need to add any new devices, add new costs, or adjust the existing network topology of the LAN, therefore, the clever use of this solution limits the speed of the LAN workstation to quickly solve the problem of slow overall speed of the LAN. Of course, this solution still has some shortcomings for enterprise local networks that are larger in size. However, at present, this solution is very suitable for small and medium-sized enterprise local networks!