Subdivision network switch Led Underground Light have
many designs, such as fixed ground light, adjustable buried ground light and
contemporary recessed design. 3W Led Underground Light,Led Underground,Led Underground Light,Led Underground Paving Light ZHONGSHAN G-LIGHTS LIGHTING CO., LTD. , https://www.glightsled.com
Broadly speaking, there are two types of switches: WAN switches and LAN switches. WAN switches are mainly used in the telecommunications field to provide a basic communication platform. Local area network switches are used in local area networks to connect terminal devices such as PCs and network printers.
According to the current complex network structure, network switches are divided into access layer switches, aggregation layer switches and core layer switches. Among them, the core layer switches all adopt the chassis type modular design, and have basically designed the 1000Base-T modules equipped with them. The Ethernet switch that supports 1000Base-T at the access layer is basically a fixed-port switch, with 10 / 100M ports as the main, and provides 1000Base-T uplink ports in the form of fixed ports or expansion slots. Aggregation layer 1000Base-T switches exist in both chassis and fixed port designs, and can provide multiple 1000Base-T ports. Generally, other forms of ports such as 1000Base-X can also be provided. The access layer and aggregation layer switches together form a complete small and medium-sized LAN solution.
From the perspective of transmission media and transmission speed, LAN switches can be divided into Ethernet switches, Fast Ethernet switches, Gigabit Ethernet switches, FDDI switches, ATM switches, and Token Ring switches. These switches are suitable for Ethernet respectively. , Fast Ethernet, FDDI, ATM and Token Ring networks.
From the scale application, there are enterprise-level switches, department-level switches and workgroup switches. The scales divided by various manufacturers are not completely consistent. Generally speaking, enterprise-level switches are rack-mounted, department-level switches can be rack-mounted or fixed-configuration, and workgroup-level switches are generally fixed-configuration. , The function is relatively simple. On the other hand, in terms of the scale of applications, as a backbone switch, switches supporting large enterprise applications with more than 500 information points are enterprise-level switches, and switches supporting medium-sized enterprises with less than 300 information points are departmental switches, while supporting 100 The switches within one information point are workgroup-level switches.
According to the architectural characteristics, people also divide LAN switches into three types: rack-mounted, fixed configuration with expansion slots, and fixed configuration without expansion slots. Rack switch is a slot-type switch, this kind of switch has better scalability, and can support different network types, such as Ethernet, Fast Ethernet, Gigabit Ethernet, ATM, Token Ring and FDDI, etc. But the price is more expensive. Many high-end switches use a rack structure. Fixed configuration switch with expansion slot is a switch with fixed ports and a small number of expansion slots. This switch can support other types of networks by expanding other network type modules on the basis of supporting fixed port type networks. The price of the switch is in the middle. Fixed configuration switches without expansion slots only support one type of network (usually Ethernet), which can be applied to local area networks in small business or office environments. The price is the cheapest and the most widely used.
According to OSI's seven-layer network model, switches can be divided into layer two switches, layer three switches, layer four switches, etc., all the way to layer seven switches. Layer 2 switches that work based on MAC addresses are the most common and are used for the network access layer and aggregation layer. Layer 3 switches that exchange based on IP addresses and protocols are commonly used in the core layer of the network, and are also used in a small amount in the aggregation layer. Some layer 3 switches also have a layer 4 switching function, which can determine the target port based on the protocol port information of the data frame. Switches above the fourth layer are called content switches and are mainly used in Internet data centers.
According to the manageability of the switch, the switch can be divided into a manageable switch and an unmanageable switch. The difference between them is the support for network management protocols such as SNMP and RMON. Manageable switches are convenient for network monitoring and traffic analysis, but the cost is relatively high. Large and medium-sized networks should choose manageable switches at the aggregation layer, depending on the application needs at the access layer, and core layer switches are all manageable switches.
According to whether the switch can be stacked, the switch can be divided into two types of stackable switches and non-stackable switches. A main purpose of designing stacking technology is to increase port density.
According to the most common general classification method, LAN switches can be divided into desktop switch (Desktop Switch), workgroup switch (Workgroup Switch) and campus network switch (Campus Switch). Desktop switches are the most common type of switches, and they are the most widely used, especially in general offices, small computer rooms, and business departments with concentrated business acceptance, multimedia production centers, and website management centers. In terms of transmission speed, most modern desktop switches provide multiple ports with 10 / 100M adaptive capability. Workgroup switches are commonly used as expansion devices. When desktop switches cannot meet the needs, most workgroup switches are directly considered. Although the workgroup switch has only a small number of ports, it supports more MAC addresses and has good expansion capabilities. The transmission speed of the ports is basically 100M. Campus network switches are relatively few applications, only used in large networks, and are generally used as the backbone switches of the network, with fast data exchange capabilities and full-duplex capabilities, can provide intelligent features such as fault tolerance, and also support expansion options and Layer 3 Various functions such as virtual local area network (VLAN) in switching.
According to the different switching technologies, some people divide the switch into three types: port switch, frame switch and cell switch. Unlike the bridge, the forwarding delay of the port switch is very small, and the operation is close to the performance of a single local area network, far exceeding the forwarding performance between ordinary bridged Internet. Port switching technology first appeared in slot-type hubs. The backplane of this type of hub is usually divided into multiple Ethernet segments, which are not connected by bridges or routers. The networks are not interconnected. After the Ethernet main module is inserted, it is usually allocated to a network segment of a backplane. Port switching is used to distribute and balance the ports of the Ethernet module among multiple network segments on the backplane. Frame switching is currently the most widely used LAN switching technology. It provides a parallel transmission mechanism by micro-segmenting traditional transmission media to reduce collision domains and obtain high bandwidth. ATM technology represents a good medicine for many problems in network and communication. ATM uses a fixed-length cell exchange of 53 bytes. Due to the fixed length, it is easy to implement in hardware. ATM uses a dedicated non-differential connection and runs in parallel. Multiple nodes can be established at the same time through a switch, but it does not affect the communication capabilities between each node. ATM also allows communication capabilities between the source node and the target node. ATM uses statistical time division circuits for multiplexing, which can greatly improve channel utilization. The bandwidth of ATM can reach 25M, 155M, 622M and even several G-bit transmission capacity.
In fact, from the perspective of application, switches can be divided into telephone exchanges (PBX) and data exchanges (Switch). Of course, the very fashionable voice transmission VoIP over data is also called "soft switch".
Fixed ground lights, fixed buried ground uplighters for driveways and pathways.
Adjustable buried ground lights, ideal for uplighting walls, fences and
features. Recessed ground lights providing a great projected light source. LED
recessed uplighters ideal for lighting up features. In ground light fittings
great for uplighting.
Contemporary recessed ground lights, great effective uplighters for a variety
of lighting effects.