Architecture of Ethernet Virtualization in Data Center

The network frame constitutes a stumbling block

The typical architecture of traditional data center Ethernet adopts tree structure, which is arranged according to three-layer switching mechanism, and is fanned out from the core. This design comes from the LAN architecture, about 10? It was adopted by the data center 15 years ago. At that time, Ethernet was in the limelight, replacing networks such as SNA, token ring and dec net. In the past 10 years, with the continuous development of the data center, the shortcomings of the network began to be exposed, including unsatisfactory performance, inherent low efficiency and too complex. Among these shortcomings, the real obstacle to building a virtualized data center is its complexity.

Complexity comes from the fundamental structure of tree structure. The network is usually composed of multiple autonomous switching devices, which work together through shared protocols. Managing the network requires not only managing the switches, but also managing the correlation between switches. With the continuous expansion of network capacity, the number of switches in the network also increases linearly. However, the increase of potential correlation between switches is related to the square of the number of switches, which can be expressed by the formula I = n * (n-1) / 2, where I refers to the number of potential correlation and N refers to the number of managed devices. It can be seen that the number of interconnected managed increases exponentially, thus increasing the complexity of the network, and as a result, curbing the benefits of virtualization.

Complexity also limits scalability. As the data center network continues to add new ports, connecting devices and traffic, the complexity of management increases exponentially, resulting in the unmanageable large layer 2 network domain. In order to limit complexity, the networks in many data centers are divided into multiple physical network segments. Unfortunately, this is contrary to the desire to build fewer and larger resource pools. In addition, complexity also curbs changes in network architecture, or the ability to quickly reconfigure the network, thus ultimately curbing dynamics.

Simplify network architecture

To overcome the network barrier, the key is to simplify the network and reconsider the network from the architecture level. Here are five specific approaches:

1. Reduce the number of physical networks to a minimum. For most companies, the first step is to combine multiple Ethernet networks into one physical network. The new data center bridging (DCB) function combined with virtual local area network (VLAN) can separate traffic and determine traffic priority. In addition, if possible, consolidate storage traffic to Ethernet networks, which can be achieved by using protocols such as NAS, iSCSI or Ethernet based fibre channel (FCoE).

2. Flatten the physical network. Nowadays, most data center networks are built with three-layer switch system. The latest technology can eliminate the aggregation layer and simplify the network to two layers without affecting the function of expanding network connection. Network flattening can reduce the number of switches and connections to be managed, greatly reduce the complexity, improve the performance and reduce the cost.

3. Migrate to the "network fabric" architecture. Compared with the traditional tree architecture, one of the important aspects of the network architecture is that all units in the network architecture are controlled by a single control plane, which is the same as that all ports in a switch are controlled by a single control plane. In fact, the network structure is a group of different physical units, which work like a logical distributed switch.

In addition, the network structure can be naturally associated with the dynamic resource pool. That is, after the virtual port (the interface between the virtual machine and the network) is defined or configured in the network structure, each physical port in the network knows the configuration. If the virtual machine is migrated on the network structure, the virtual port configuration will be saved automatically, and the connection relationship between the virtual machine and other networking resources will be preserved. These networking resources include storage systems, load balancers, security devices, and edge services (routers). It also automatically protects traffic separation mechanisms, including access control lists (ACLS), virtual LANs, and policy definitions. These all enhance the dynamics of the resource pool.

4. Designed for single point management. Strive to design such an architecture: the management of virtual and physical networks can be treated as a "task" by using only a set of automation tools. This is expected to eliminate many common configuration errors that occur when different people are responsible for configuring virtual and physical switches (using different tools or interfaces). If these configurations are not synchronized, problems may occur when the virtual machine is initially configured or migrated.

5. Plan and implement virtual Ethernet port aggregation (VEPA). VEPA (virtual Ethernet port aggregation, 802.1 QBG) is an emerging open standard, which is expected to improve the relationship between network and Virtualization Server. It separates the task of switching from the hypervisor and completely depends on the physical network. In this way, virtual switches can act as pass through devices, eliminating the entire switching layer, thereby significantly reducing the number of switches and interconnections that need to be actively managed. It also hopes to improve the network signaling mechanism supporting virtual machine migration, so as to improve the dynamics. Assuming that the hypervisor and switch support VEPA, VEPA allows seamless migration of virtual machines across the network.

In order to get the full benefits of virtualization and enjoy a more scalable and dynamic resource pool, we need to redesign the data center network architecture to eliminate its inherent complexity.

Architecture of Ethernet Virtualization in Data Center 1

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The Engineering Institute of Tsinghua University Develops a Flexible Green Multi-mode Access Data Ce
The Engineering Institute of Tsinghua University Develops a Flexible Green Multi-mode Access Data Ce
Hengtong optoelectronics signed a strategic cooperation agreement with the Institute of Engineering Thermophysics of the school of Aeronautics and Astronautics of Tsinghua University in Beijing. The two sides carried out in-depth cooperation around realizing technology R & D and resource integration, building a Green Data Center Research Institute, promoting the technology iteration of green flexible intelligent data center and accelerating the industrialization process. Zhang Xing, director of Institute of thermophysics, School of Aeronautics and Astronautics, Tsinghua University, vice president of China Society of Engineering Thermophysics and President of international heat transfer Council, Li Zhen, deputy director of Institute of thermophysics, School of Aeronautics and Astronautics, Tsinghua University, he Zhiguang, postdoctoral of School of Aeronautics and Astronautics, Tsinghua University, and Pang Shengqing, vice president of Hengtong group attended the signing ceremony.Hao Xiangyong, director of the technology center of Hengtong communication industry group, and Zhang Xing, Institute of Engineering Thermophysics, School of Aeronautics and Astronautics, Tsinghua University, China Mobile signed the contract on behalf of both parties. Li Zhen, deputy director of the Institute of special physics, School of Aeronautics and Astronautics, Tsinghua University, sun Yixing, Hengtong new industry development group, Yin Jicheng, Hengtong communication industry group, Wei Zhongcheng, Technology Research Institute of Hengtong group, etc. witnessed the signing.Zhang Xing said at the signing ceremony that the engineering thermophysics discipline of Tsinghua University was founded in 1958. Relying on the Key Laboratory of thermal science and power engineering of the Ministry of education, the Institute ranked first in the national first-class discipline evaluation of power engineering and Engineering Thermophysics for many times. At present, the Institute has formed many characteristic research directions represented by new concept thermodynamics and micro nano scale heat transfer. Among them, the research on fire accumulation theory was successfully selected into the top 10 hot frontier of Thomson Reuters in 2014, which has had a wide impact in the world. Zhang Xing revealed that energy consumption has always been a key technical problem in the development of large data centers. The Institute has developed a flexible green multi-mode access data center solution by using its technical R & D force in the thermal direction. Hengtong optoelectronics is one of the top three optical fiber communication companies in the world. It has strong capabilities in R & D, manufacturing, integration and general contracting of core products in the data center. This strategic cooperation with Hengtong Optoelectronics in the R & D and business of the data center is committed to the rapid industrialization and market promotion of the latest iteration of low-energy green intelligent technology.Pang Shengqing, vice president of Hengtong group, said that the edge, large, medium and small data centers and other series solutions launched by Hengtong optoelectronics also take flexibility, green and intelligence as the design concept. It adopts a standardized installation mode and has the ability of rapid deployment, which can help users quickly build the cloud management side-end network architecture. At the same time, according to user needs and application scenarios, the heat dissipation scheme can be flexibly adjusted and selected to realize flexible heat dissipation and accurate refrigeration. In addition, it also has the ability of all-round monitoring and dynamic intelligent management. "It can be said that Hengtong optoelectronics can provide a full range of data center solutions from design, construction to EPS turnkey services. This cooperation with the Institute of Engineering Thermophysics of the school of aerospace and aeronautics of Tsinghua University focuses on overcoming flexible heat dissipation and precision refrigeration technologies and building a life-cycle data center construction scheme. We are very honored and confident to contribute to the development of big data in the future The strategic needs of the people. "With the continuous promotion of 5g construction and the rapid development of cloud computing, Internet of things, big data and artificial intelligence, human economy has entered the era of digital economy from network economy, and the disadvantages of traditional data center are gradually emerging. The first highlight is the shortcomings of the traditional data room, such as low maintenance efficiency, long construction cycle, high energy consumption and so on. Therefore, building a "wider, more flexible and faster" new data center has become an urgent demand of the whole society.The micro module data center developed by Hengtong optoelectronics integrates the power distribution, air conditioning, wiring, cabinet, fire protection, monitoring, lighting and other systems of the traditional computer room into an integrated product, which can realize the rapid and flexible deployment of the system, and is easy to expand and maintain. It can not only reduce the construction cycle, but also reduce energy consumption. At the same time, it helps users quickly build a cloud, management, edge and end network architecture, form a series of data center solutions, and build a comprehensive service capacity for building a multi solution green series of data centers.
Why Do in Rooms Data Center Cooling Units Have the Return Air Positioned at the Bottom When Hotter A
I have never, ever seen a return air positioned anywhere but high up in any datacenter I have ever been inside of in over a quarter century of datacenter experience. I bet I have been inside around a hundred facilities of all sorts of configurations, from traditional chiller-based cooling, to AC/DX style, to fresh air/evaporative cooling. All have used return air higher up, either at ceiling height or ducted through the ceiling with containment. So if you have seen one it is an anomaly.That said, pressure differential does more for moving air than "relative altitude within the room" but when you're designing a datacenter you use as much natural assistance from physics as you can to make things more efficient.Why do in rooms data center cooling units have the return air positioned at the bottom when hotter air tends to rise up and away from the floor?.1. 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Is one any better than the other? Let's explore each option and see. DIY freon refresh sets abound. Unfortunately, they just address one specific problem, however, and may miss something more serious. Recharging lost freon might offer you short-term relief but subjects the environment to unsafe chemicals when the system loses freon once again. This choice is the riskiest as a lot of us are not licensed air conditioning repair professionals. You run the risk of squandering money on an inadequate are pair' and damaging the environment. Independent service centers are better than DIY as they have the knowledge and (likely) the tools required for an effective car air conditioning repair. While the technicians will certainly have a far better opportunity of effectively identifying the problem with your vehicle's air conditioning, they might not have all the customized equipment needed to successfully fix it. Independent repair shops are made to service various brands of automobiles, not always your vehicle specifically. Your local dealer is absolutely your ideal option when fixing anything on your vehicle and that includes getting your car air conditioning serviced. The dealership professionals are particularly educated on your vehicle and have access to any kind of specialized equipment and manufacturer replacement components that could be needed to efficiently repair your vehicle's cooling trouble. All three choices have their advantages when it pertains to repairing your car's cooling, yet here at Bob Howard Acura, we have the right devices to correctly diagnose your problem and fix it correctly. What is the Price of an AC Diagnostic? The very first part of repairing your car's air conditioner is recognizing what is broken. This means more than discovering that the car or truck's AC system does not blow cold any longer. The expense of an AC diagnostic can differ substantially depending upon how extensive the diagnostic test is. Some places like the automobile parts store or independent repair shops might only have the ability to evaluate for freon leakages while we have the specific equipment required to correctly fix your vehicle's AC trouble. We recognize that one size does not fit all and we will personalize the A/C diagnostics test for your specific requirements. Ultimately your automobile's AC system quit working because of a leak or a component failure, it likely will never just require a are charge'. Cooling units are cooled down by freon, a chemical that can be unsafe to the atmosphere. So, while you may be most concerned about your loss of cold air, a broken car cooling system may be damaging to the atmosphere and must be inspected immediately.
Directorpoint Celebrates the Launch of a European Data Center
Directorpoint Celebrates the Launch of a European Data Center
Big news from the Directorpoint team! This summer has seen our company reach several milestones.New Directorpoint European Data CenterDirectorpoint is thrilled to announce the opening of an official headquarters and data center in the UK. As our number of European clients has grown, we have actively pursued ways to improve their product experience. The establishment of the data center, in particular, will allow clients in the European Union to experience significantly faster download and upload speeds while using our software. The Directorpoint team sees this European expansion as the next step for extending its international reach.Full Press ReleaseBirmingham-Based Directorpoint Expands to the UKBirmingham-based Directorpoint has established an official UK headquarters and data center in order to better serve its growing base of European clients. Companies and nonprofit organizations in the European Union utilize Directorpoints board management software to enhance boardroom communications and to better overall board decision-making.The creation of the data center will deliver significant software performance improvements for clients in the European Union particularly in file upload and download speeds.The Directorpoint team sees this expansion as the next step for extending its international reach. Directorpoint co-founder and President, John Peinhardt, shares, Were very excited to continue our international growth, and this new data center will ensure that we can provide an exceptional experience to users living outside of the United States. Our physical and digital expansion into Europe will help us serve those customers even more effectively.Directorpoint, which currently serves companies located in 13 countries, is pursuing similar headquarter and data center developments globally. John Peinhardt and Ellen Glasgow founded Directorpoint in 2012. Directorpoint has quickly emerged as a leader in the board software tech sector. The software as a service (SaaS) company provides board management software to maximize board effectiveness. With offices in the United States, Australia, Canada, and Europe, Directorpoints global footprint supports client boards in pursuit of their ambitious missions.Originally published at on August 8, 2018
Back to School Help!Read Details! Get 10Points For1 with Best Outfit!?
Back to School Help!Read Details! Get 10Points For1 with Best Outfit!?
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Design Scheme of Multi-channel Voltage Measurement Based on Stm32
Design Scheme of Multi-channel Voltage Measurement Based on Stm32
This design proposes a design scheme of multi-channel voltage measurement based on STM32 chip, and the measurement range is between 0-10V. The built-in A / D of STM32 samples the multi-channel voltage values to obtain the corresponding digital quantity. Then the corresponding analog voltage value is obtained according to the proportional relationship between digital quantity and analog quantity, which is displayed by TFTLCD display equipment, and the multi-channel collected data is stored in SD card.1. IntroductionIn recent years, data acquisition and its application have attracted more and more attention, and data acquisition system has developed rapidly. It can be widely used in various fields.Data acquisition technology is one of the important branches of information science. Data acquisition is also a process of obtaining object information from one or more signals. Data acquisition is an important link in industrial control systems. It is usually realized by some single chip microcomputer systems with relatively independent functions. As an indispensable part of the measurement and control system, the performance characteristics of data acquisition directly affect the whole system.Voltage measurement is the most universal. It is of great significance to study and design methods and instruments to improve voltage measurement accuracy. In the design of voltage measurement, single chip microcomputer as controller is the core of the whole design. In addition, there must be an analog-to-digital converter (ADC) in the design. ADC is used to directly collect analog voltage and convert analog signal into digital signal. It directly affects the accuracy and speed of data acquisition.2. System overviewThe microcontroller of this design adopts STM32 single chip microcomputer.STM32 Series MCU is designed based on the Cortex-M3 core of arm company. Its clock frequency reaches 72mhz. It is a high-performance product among similar products. It has the advantages of high performance, low cost and low power consumption. It is a good choice in embedded application design. The A / D converter in the design adopts STM32 built-in ADC. STM32 ADC is a 12 bit successive approximation analog-to-digital converter.It has up to 18 channels and can measure 16 external and 2 internal signal sources. The A / D conversion of each channel can be performed in single, continuous, scanning or intermittent mode. The conversion results can be stored in the 16 bit data register in left or right alignment. The maximum input clock can reach 14mhzThis design can measure the voltage value of 8 channels, the measurement range is 0-10V, and the display error is ± 0.001V. LCD displays the voltage value and waveform in real time, and microSD card synchronously stores the data. The system principle block diagram is shown in Figure 1.Design scheme of multi-channel voltage measurement based on stm323.3 LCD control circuitThe LCD used in this design is 2.4 inches, 320 & times; 240 resolution. The LCD module is controlled by the FSMC interface of STM32.FSMC (flexible static memory controller) can be changed into static storage controller. It is a unique storage control mechanism of STM32 series high storage density microcontroller with internal integration of flash of more than 256Kb and suffixes Xc, XD and Xe. By setting the special function register, FSMC can send corresponding data / address / control signal types according to different external memory types to match the speed of the signal, so that STM32 series microcontrollers can not only apply various external static memories of different types and speeds, Moreover, it can expand a variety of different types of static memory without adding external devices, so as to meet the comprehensive requirements of system design for storage capacity, product volume and cost.In STM32, one end of FSMC is connected to core Cortex-M3 through internal high-speed bus AHB, and the other end is an external bus for extended memory. After the access signal of the kernel to the external memory is sent to the AHB bus, it is converted into a signal conforming to the communication protocol of the external memory through the FSMC and sent to the corresponding pin of the external memory to realize the data interaction between the kernel and the external memory. FSMC acts as a bridge, which can not only convert the signal type, but also adjust the signal width and timing, so as to shield the differences of different storage types and make them no difference to the kernel.FSMC can connect devices such as nor / PSRAM / NAND / PC card, and has FSMC_ A [25:0] has 26 address buses and FSMC [15:0] has 16 data buses. In addition, the extended storage space of FSMC is divided into 8 blocks. Select the block of the operation through the address line. In this way, the LCD will operate as a memory with one address space.3.4 SD card drive circuitThe SD card used in this design is microSD, also known as TF card. MicroSD card is a very small flash memory card, which is mainly used in mobile phones. However, due to its small volume and the continuous improvement of storage capacity, it has been used in GPS devices, portable music players, digital cameras and some flash memory disks. The pin diagram of microSD card is shown in Figure 9.MicroSD card, like SD card, has SPI and SDIO operation buses. Compared with SDIO bus, SPI bus has simple interface, but its speed is slow. We use SDIO mode.MicroSD card has 4 data lines in SDIO mode.In fact, microSD has 1-wire mode and 4-wire mode in SDIO mode, that is, 1 or 4 data lines are used respectively. Of course, the speed of 4-wire mode is faster than that of 1-wire mode, but the operation is more complex. The 4-wire mode of SDIO is used in this design. The hardware connection diagram of microSD card is shown in Figure 3.STM32 MCU Chinese official websiteSTMicroelectronics / St / STM
How Does Temperature Affect the Speed of Sound?
How Does Temperature Affect the Speed of Sound?
As other answers show, the speed of sound is slightly influenced by temperature.Much more interesting is the influence of gradients in temperature! The usual distribution of temperature at different heights is: high at ground level, decreasing upwards. This profile, with slightly higher sound velocity at ground level causes wave fronts to curve upwards. Sometimes the temperature profile is inverse, from ground level to a certain height, in the order of hundreds of meters. This inversion layer acts as a reflector, causing sound to propagate over much larger distances.It is not the speed as such, but the differences in speed that have important influence on sound propagation.1. How to increase my running speed?No, leaping prime does now not make you a quicker runner. Speed is muscular so you will do whole frame paintings along side plyometrics, which can be exceptional varieties of bounding and leaping to construct explosive force. To get greater at going for walks you ought to run. If you are employed on lifting and doing the plyometrics you are going to have the groundwork to upgrade your going for walks. What form of going for walks are you running for? If it's soccer then you definitely will have to coach for brief bursts of velocity. If it's one other game you have got to appear on the distances required on your game. A huge aspect of velocity it response. That manner the begin. Whether it's out of the blocks in a race, or attending to a fly ball within the outfield. Speed is vigor so that you ought to be ready to loosen up rise up tall, maintain your elbows at ninety levels, swing them directly entrance to again, and now not throughout your frame. Land at the balls of your ft.2. Water flows through a 1.5 cm diameter pipe into a 275 liter bathtub, which it fills in 5 minutes. What is the speed of the water in the pipe?Mass of 275 litres of Water divided by 5 minutes x 60 seconds = Time of 300 secondsMass Flow Rate of 0.9166 litres per secondThis is excessive amount of water in Speed or Velocity to fill a bathtub in 300 seconds. See IPHE & CIBSE CoP & Technical Guidance on maximum flow rate for 15 mm smooth wall copper pipework. The water pressure is another factor is consider.Water flows through a 1.5 cm diameter pipe into a 275 liter bathtub, which it fills in 5 minutes. What is the speed of the water in the pipe?.3. Not getting the download speed I should be getting?you download a file to what ? a phone or a computer? ethernet or wirelessly ? you need to be more clear on how to ask a question, even with my godlike powers i cant read your mind4. Need help gaining speed/trimming fat?challenging task. browse in google. that will may help!5. Why are people so insistent that speed of light is constant for all observers and is the maximum traveling speed?In special relativity, when the speed of light is constant for everyone, time can be different. When different travellers or observers have light remain constant, their time can change to allow for this. So try to wrap your head around the fact that different observers can have differences in time, and this allows the speed of light to remain constant for all observers.6. fur nice fan motor Polly have to be smaller to make the fan go faster?Motor pulley larger or driven pulley smaller will increase speed7. What are the technical factors in a processor that determine its speed?Clock Speed of the Processor and its primary cache size determines its speed in terms of throughput8. Is faster than the speed of light possible?well ist just a theory so it could be or couldnt be true.....einstien said if we could go the speed of light then we cold time travel...other people say it is still expanding....what i want to know is how can all of that crap fit into somthing the size of a pin head lol.9. How to train for faster picking speed on guitar?Assuming we are talking about alternate picking, there are basically two exercise methods for building speed.The first and the better known one is to start slow. Set your metronome to a comfortable tempo and play the exercise a few times. Then go up 2 bpms or so and repeat. Continue alternating between plus two and minus one. Back down some 10 bpm when you hit your limit and work your way up from there again. You can go up 10 bpm or so from time to time just to see how it feels. The second one is to practice in bursts. Start with two notes and play as fast as you can. Then add the third and continue from there. This method is not as well known as the first one but is every bit as useful. You can also start from the most difficult spot on the exercise and add notes on both sides.Practicing scales only is probably not the best way to go. There are specially crafted exercise sets to build speed that isolate common patterns. Troy Stetina's book Speed Mechanics contains one such set.In terms of technique, on your left hand, only apply enough pressure to avoid buzz. You will get tired very quickly if you exert more force than necessary. The lighter your left hand touch is, the easier it is to play fast. It's easier said than done but that's the whole idea of practicing.On your right hand, I would not worry that much about wrist vs. elbow unless you are aiming for Guiness speed record. Wrist movement is probably a bit better but there's nothing wrong with a combination of wrist and elbow. Guitarists argue about it all the time but there are superb guitarists in both camps which proves that both techniques are equally viable. Just avoid finger movement, it does not work for fast playing
What Is WiFi? Just Tell Me What It Is, and What It's Used For.?
What Is WiFi? Just Tell Me What It Is, and What It's Used For.?
Wi-Fi= wireless fidelity and what everyone else said1. i want to acess internet on my psp and my pc.i heard about this wifi link.i don't what a wifi is.plz help?you are not going to get free internet. if you want internet you have to pay for it. all Wi-Fi is, is you plugging a router into your internet connection, then the router transmits a signal.2. What WiFi router should I buy for my 800 SF apartment?Any wifi router provided by the internet provider will do and serve the purpose...An apartment area of 800 sq. ft is small enough which can easily be served by the company provided hardwares!You would not want to have a very strong signal that anyone outside your apartment can tap into!3. What is wifi and how do I know if my house has it?Wi-Fi is a wireless internet connection that things like laptops, wireless cards, and game systems use connect to the internet. If you do not have a wireless router, you do not have Wi-Fi4. What Wifi usb Adpter Is Better?Neither, they are both low quality. Buy from a reputable brand5. what is wifi actually? how does it works?it's a wireless connection. you can connect any computing device as long as you have a wireless nic enabled on that certain device. to access the internet you need to be in a "hotspot" that's the place where you can get your signal to connect to the internet6. How can I find out what Wifi networks my iPhone knows about?I think the only way is to actually be in range of the network that you want to get rid of. You can not actually see what networks you have stored, not that I know of, but if you want to get rid of a network.Settings > Wifi > Then select the blue arrow on the right of the network that you are connected to and click "Forget this Network".7. How do I find out what wifi chipset my phone has?I simply used the dmesg command in a terminal emulator and scrolled until I found anything named bcm432x... and wlan. Think thats it. I have lg p5008. I'm not entirely sure what WiFi is?Have a look at the wikipedia article. Usually you would get a DSL connection and set up your wireless network at home. The wireless network connection is also called W-LAN or WiFi, but in this context, WiFi has nothing to do with the ISP. Not sure if in your region any provider sells internet acces via WiFi, this is not a common thing to do.9. What is wifi and what does it do for a phone?If you have internet at home and have a wireless router you can connect wirelessly to it and get on the internet etc. on your phone. Hope this helps!10. 802.11 standards compliant methods of forming a LAN. Unlike Ethernet, data does not travel along a cable, but rather, wirelessly, at a frequency of 2.4GHz (802.11b/g) or 5.0GHz (802.11n and the antiquated 802.11a)11. What is "WiFi" and can you explain ,more about it? I'm GOnna buy a laptop.?well if you want wifi in your home you have to have an internet connection threw a modem..ex comcast, qwest, at&t. you will need to purchase a wireless router, its just another device that hooks into your modem. so no it is not free, but it is a one time charge because your ISP will not charge you to have the wireless router hooked up...and where you can use it is in your home. you can also connect to wifi at places like starbucks, and that is free as well.12. What WiFi router brands or models are considered to be secure? [closed]For cheap solution I use a wifi router well supported by dd-wrt alternative firmware. Here you can find supported models database.For more advanced, trouble-safe solution I use Ubiquiti UniFi - the AC-Lite model is really good.13. What is a bluetooth? what is WIFI? And what is a BLU RAY DVD?Bluetooth is a wireless technology for connecting electronic devices to each other. For instance there are Bluetooth Headphones, Bluetooth Cell Phone Ear Pieces, etc... If you want to be able to use the Bluetooth Ear Pieces with your cellphone, your cellphone must be Bluetooth compatible. WiFi is a method of connecting to the internet wirelessly. For instance many big cities may have "WiFi Hotspots". If you are in these WiFi Hotspots and you have your laptop or any other device that can connect to the internet wirelessly, you can surf the web wirelessly as long as you are in that particular area. And Blu-Ray is Sony's High Definition format disc. The difference between Blu-Ray and Regular DVD is that Blu-Ray can produce 1080p HD quality picture and Blu-Ray can hold more data. A Single Layer Blu-Ray disc can hold 25GB and a Dual Layer DVD can hold 50GB. A standard DVD can only hold around 8.5GB total. Basically if you have a HDTV, Blu-Ray would be the best choice for getting the best picture quality with clear, crisp viewing quality.
Which Is Better, WiFi Or ZigBee Wireless Technology
Which Is Better, WiFi Or ZigBee Wireless Technology
Wireless replacing wired has become an irreversible trend, which can also be said to be a new industry. At present, there are two technical camps of ZigBee and WiFi in the field of smart home, and WiFi and ZigBee have their own advantages in wireless technology. Among the most popular wireless technologies in the industry, WiFi technology and ZigBee technology are the most worthy of competition. So which is more advantageous, WiFi or ZigBee? Who will become the mainstream in the future? This is worth discussing.WiFi: WiFi technology is the fastest transmission technology at present. The product cost is low and it is more popular in current life. However, the devices that can be connected with WiFi are limited. The actual scale of adding WiFi network to devices generally will not exceed 16. In the development of, the number of switches, lighting and home appliances will certainly be far more than 16, so WiFi has its advantages, but it has great limitations, Limited development.ZigBee is a two-way wireless communication technology with low complexity, high security and short-range transmission. It has the characteristics of strong scalability and can be embedded in various household devices. ZigBee also has advantages in security.1. The future smart home network will be a smart network, which can sensitively perceive the changes of data and traffic of each node; Be able to intelligently allocate, repair and deal with network resources; It has the attribute of "self-learning and self-organization".. However, in the practical application of families, switches, lighting, curtains, anti-theft devices, etc. will not move after installation.2. ZigBee supports up to 65000 nodes, but can WiFi connect more than 100 devices? The answer is No. So large capacity is good.For example, LVMI smart home, that is, Xiaomi's smart home brand, basically supports ZigBee protocol.When it comes to LVMI, I recommend their smart gateway. The smart home market is very messy. Sometimes we are excited to buy it and find that it does not support it. Therefore, when we buy it, we should see what the device supports or does not support. Of course, the best thing is to buy a gateway with high compatibility. LVMI's gateway product not only supports ZigBee protocol, but also is compatible with homekit. This product supports 32 aqara devices of green rice, which can be connected with Apple's "home" app. After that, it can control the associated devices on IOS devices and Siri directly. I think most young people now use fruit machines to compare prices. In this way, it is still very friendly to most IOS users. For fruit powder users, the biggest advantage of this product is price. At present, the smart home products supporting homekit on Apple's official website are very expensive. Even a simple smart socket costs 295 yuan. Through the aqara gateway of LVMI, the cost of access equipment can be reduced.Well, comprehensive comparison, WiFi is relatively more convenient, but ZigBee will be more stable and support more devices. If you only want to use one or two smart devices, WiFi can be used. If you want to create a complete set of smart home ecological chain, it is obvious that ZigBee is more in line with your requirements. Xiaobian is more optimistic about ZigBee. After all, home is developing towards the trend of comprehensive intelligence, Technology with multiple devices can ensure this. No matter what kind of technology, we hope to constantly update and improve, and making our products convenient is the king.
Smart Home Promotes Building Intercom into Thousands of Households, with Large Stock and Incremental
Smart Home Promotes Building Intercom into Thousands of Households, with Large Stock and Incremental
In the large densely populated cities of Beijing, Shanghai, Guangzhou and Shenzhen and the rising second and third tier cities, the housing demand is increasing year by year. The huge floating population not only promotes the rapid development of low-end real estate resources in the first tier cities, but also extends the complex industrial chain around the buildings. In particular, the development slogan of "smart city" put forward by the state in recent two years gives hope to the market that lives on security products around buildings in addition to real estate developers.Smart home promotes building intercom into thousands of householdsAt present, more and more building intercom manufacturers begin to go deep into the field of smart home and combine building intercom system with smart home system. This is reflected in the construction of "digital building" and "smart home industry ecosystem":Combined with the smart home system, in addition to the traditional intercom unlocking function, the building intercom also integrates many convenient functions such as SMS notification, mobile app remote control, security alarm, indoor monitoring and viewing, elevator call, home control, information home and so on.Building intercom and smart home complement each other, further improving the value-added space and cost performance of both, thus bringing huge space for function expansion.In the future, it is expected to take advantage of the upsurge of smart home to develop rapidly in the wave of home intelligence, and will carry more home control functions.Smart community derived demand brings new business opportunities for building intercomIn addition to the smart home, the building intercom system, as the entrance of the smart community, realizes the extension of multiple functions such as identity confirmation, access control, security monitoring, human-computer interaction and so on by combining AI technology.The consumer demand derived from the smart community can be said to bring new business opportunities to the building intercom industry. In the process of continuous promotion of the smart community, many building intercom enterprises see the future business opportunities and begin to make corresponding layout and planning on products and solutions. Using information means, Internet and Internet of things technology, develop community oriented Internet of things system and information platform, and provide real-time, fast, efficient and low-cost Internet of things, interconnection and intelligence for the community on this basis. For example, it launched smart community management, smart life services, smart travel and other related solutions, and continued to pay attention to the field of community and personal security.High, middle and low-end take all stock and incremental market space is largeAs an upstream industry of real estate, building intercom has significantly increased the demand for medium and low-end building intercom products under the condition that the state vigorously promotes the construction of affordable housing and indemnificatory housing.With the implementation of smart city construction, the demand for high-end building intercom products is also increasing day by day. The application of high-definition visualization and face recognition in the field of building intercom is accelerating.At the same time, after more than 20 years of development, many communities equipped with building intercom in the early stage are facing problems such as disrepair and backward configuration. Therefore, the equipment renewal demand of old communities has also become a new round of market growth point of building intercom system.Overall, China's housing market will continue to develop. According to the relevant development strategies of the State Council, China will build 10 billion square meters of housing by 2020. For building intercom enterprises, there is a large development space for building intercom related products in both stock market and incremental market.Conclusion: in a word, opening up the integration and docking with comprehensive life service platforms and community operation platforms such as third-party payment, smart city, video surveillance, community o2o e-commerce, smart home and community elderly care, that is to provide overall solutions for communities and families, which has become the future development trend of deepening reform, transformation and upgrading of building intercom enterprises. Moreover, with the gradual improvement of community infrastructure, building intercom enterprises also need to change from the role of product provider to the role of supporting service provider.
Upgrading of Set Top Box
Upgrading of Set Top Box
Cable STB From 1990 to 2005, the first generation set-top box, also known as analog TV set-top box, dominated the family living room for 15 years. However, due to the unidirectional content and low definition, it also replaced as the second generation set-top box - Digital TV set-top box as CRT TV withdrew from the historical stage. Although the definition of digital TV set-top box has changed greatly, the unidirectional content of both the first and second generation set-top boxes still fails to meet the needs of users. However, the second-generation TV set-top box still has a very large market. It carries the main way of radio and television live broadcasting. It has been in service until today. With the popularization of Internet and triple play, the second-generation TV set-top box has added interactivity.IPTV set top boxIPTV (Internet Protocol Television), namely network protocol television, is a technology that uses broadband network and integrates Internet, multimedia, communication and other technologies to provide home users with a variety of interactive video services, including digital TV. Its three major functions of live broadcasting, watching back and time shift turn the originally linear TV programs into a nonlinear program stream. Users can choose programs instead of watching programs, which is a great subversion to the viewing habits of traditional cable TV users. In 2004, China's IPTV was jointly launched by Heilongjiang Unicom (formerly Netcom) and Shanghai Wenguang blockbuster in Harbin, and then expanded to other provinces and cities in China. After the exploration stage from 2004 to 2008, the launch stage from 2009 to 2012 and the promotion stage from 2013 to 2017, IPTV has developed very rapidly in China.Ott boxNetwork STB began to rise in 2005, also known as Ott box. Ott not only provides free video viewing without monthly rent, but also can realize on-demand service. At this time, the network STB can only realize the function of online on-demand. Until 2007, Jingchen solved the problem of decoding, the network STB added the local playback function, and then Android in 2011   The entry of TV platform has made a qualitative leap in the network set-top box industry. The Ott industry has changed from "pseudo two-way" to full two-way. The Android TV platform has fundamentally solved the problem of openness. The network set-top box has entered the era of intelligent network set-top box, and the box industry has entered a period of rapid prosperity and development. From 2011 to 2015, the intelligent network set-top box based on 32-bit software and hardware processing system gradually developed into dual core, quad core and 8-core, and the hardware performance tended to be improved. The Android version was from 1.6 to 4.2, and the software became more and more mature, supporting 4K display resolution. Since 2015, the intelligent network set-top box based on 64 bit software and hardware processing system has become popular, The mainstream box is equipped with 1GB or 2GB of running memory, bringing scalable intelligent applications with strong hardware and software.
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