What Is a Home Area Network?

Home Network is a family information platform that integrates home control network and multimedia information network. It is used to implement information equipment, communication equipment, entertainment equipment, household appliances, automation equipment, lighting equipment, security (monitoring) in the home ) Interconnection and management of devices, water and electricity heat meter equipment, home help alarms, and other systems, as well as data and multimedia information sharing systems. Involved in telecommunications, home appliances, IT and other industries.

From a product perspective, it involves manufacturers of communication network equipment and terminal equipment, chip providers, software providers and terminal equipment manufacturers in the IT industry, as well as manufacturers of home appliances. It should be said that the understanding of home networking in these industries is not exactly the same.

Chinese name: Home network
Foreign name: Home Network

Applied discipline: computer science
Involved industry: Telecom, home appliances, IT, etc.

Home Network Home Network Status

China has issued six home network standards covering the home network architecture, home main network communication protocol, home subnet communication protocol, home device description specifications, and conformance test specifications. They constitute the home network standard system. Basic Agreement. These six standards are: SJ / T 11312-2005 "Home Main Network Communication Protocol Specification", SJ / T 11313-2005 "Home Main Network Interface Conformance Test Specification", SJ / T 11314-2005 "Home Control Subnet Communication Protocol Specification ", SJ / T 11315-2005" Conformance Test Specification for Home Control Subnet Interface ", SJ / T 11316-2005" Home Network System Architecture and Reference Model ", and SJ / T 11317-2005" Home Network Device Description File Specification. ^[1]

To establish a home network system, we must first determine the components of the home network, the interrelationships, functions and roles between the various components, and the basic issues of home network applications and coverage. "Home Network System Architecture and Reference Model" plays this role. This standard gives the standard system framework and basic structure of the home network, which is the basis of the entire standard system. ^[1]

The home network system architecture divides the home network system into a home main network and a home control subnet: the home main network transmits high-speed information (including audio and video information), which requires a relatively wide bandwidth and a relatively high cost of communication modules; the home control subnet transmission Low-speed information (control information) requires a relatively narrow bandwidth, and the cost of the communication module is relatively low. Proposing such an architecture has been unanimously approved by members of the standards working group, and is also considered to be the most reasonable in the industry and meets the needs of home network applications. ^[1]

"Home Network Communication Protocol Specification" is a high-speed data network composed of devices with high-performance processing and communication capabilities within the home. Based on actual needs, according to the existing main network equipment, wired or wireless physical transmission media are used in the home main network. For wired physical transmission media, wired Ethernet is used directly. For wireless physical transmission media, consider using IEEE 802.11 and the UWB protocol that is being specified and perfected; the network layer uniformly uses the TCP / IP protocol. The reason for making this choice is that most of the devices now support the above two protocols, and there is no need to add new hardware interfaces and basic communication software in the home network, which saves costs; the second is that the home main network devices often directly To communicate with the Internet or other broadband network information service provider systems, the use of a consistent communication protocol reduces the complexity of the use of the home main network equipment. The "Home Mainnet Communication Protocol Specification" focuses on standardizing IP address resolution and remote access management of the home main gateway, information exchange between the main network and subnets, and software application program interfaces of the home main gateway. The use of remote access in the network and the use of value-added services. For the main applications of communication protocols, such as device management, service discovery, and network security, the current industry standards have been adopted, and no new standards have been formulated. ^[1]

The "Home Control Subnet Communication Protocol Specification" specifies the technical specifications for control and status information transfer and management between home devices. In the home control subnet communication protocol, the underlying communication determines the wired and wireless physical transmission media, a communication protocol with independent intellectual property rights, and specifies the scalability of the protocol to support other physical transmission media including power line carriers. ^[1]

From the perspective of the application prospects of home network systems, wireless physical transmission media systems are generally optimistic. In the related technology research and development process, the first problem that must be faced is the frequency of wireless transmission. To this end, the standard working group The Administration submitted an application and communicated with experts from the National Radio Administration for several times. The radio frequencies of the wireless home control subnet applications have been determined: 430-432MHz and 779-787MHz.

The "Home Network Device Description File Specification" resolves the direct contradiction between the requirements for information consistency between home network device communications and the personalization of multiple home network device functions, performance, and user interfaces. The device description file provides an organization format and method for the description content of a home network device, so that each device manufacturer can retain all the characteristics of the device itself, and ordinary users do not need to update the remote control, gateway and other management controls when using these devices The hardware or software of the device is plug and play. The main role of a device description file is to describe the device's functions, control commands, and user interface. When a device joins a home network system, remote controls, gateways, and other devices can automatically generate the device by obtaining the device's description file. Management and use interface. The device description file solves the problem that the products produced by different manufacturers are not identical in terms of functions, parameters, and control methods. ^[1]

"Home Main Network Interface Conformance Test Specification" and "Home Control Subnet Interface Conformance Test Specification" are a technical reference for home network product and service manufacturers to develop products that support home network standards. These two standards are for home mainnet and subnet respectively, and regulate the rules that must be followed for devices that support home network mainnet and subnet standards. They are the technical specification foundation of the home network protocol conformance test platform. ^[1]

As people's living standards improve, more and more PCs and audio and video equipment will be installed at home. Residents require that information can be obtained from the Internet anywhere in the home, and files, printers, scanners, audio and video equipment can be shared; in the house, around the house or away from the house, the lights, water heaters, air conditioners in the house can be turned on or off And home security systems to effectively manage communication channels, such as assigning telephone lines to telephone, fax, and Internet access. To achieve these functions, you need to set up a network in your home and connect different devices to work together. Establishing a network using a wired method will bring a lot of inconvenience. If you use a wireless method to establish a network, it will greatly improve its flexibility and practicability. At present, many well-known companies in the world are developing wireless home-based intelligent systems. This is one of the development directions of home intelligent systems. ^[1]

The home wireless network must have effective anti-jamming, especially for the increasing number of wireless devices and equipment in the home that emit RF noise; the communication range must be sufficient to cover a typical home, allowing devices in the house and devices anywhere near the house Communicate with each other; have high security to prevent the intrusion of illegal users; at any time, in the house or even away from the house, the entire network should be able to quickly access; the cost must be moderate, and the price must make most consumers Can accept. In short, this wireless network should be easy to use, reasonably priced, easy to access, and capable of transmitting voice and data information. ^[1]

Wireless home networks are not limited by the location of transmission lines, telephone jacks or power outlets, and have a high degree of flexibility, avoiding a series of problems such as difficult wiring, expensive cables, and the need for professional installation and commissioning. It has broad development prospects, and commercial groups representing their respective interests have launched fierce competition for wireless home network standards. ^[1]

Home network wiring introduction

Home Network Introduction

At present, the community broadband network is rapidly spreading, and some families already have more than two computers, so the establishment of a small local area network at home has become a need to adapt to development. Especially for those who have just bought a new house and are preparing to renovate, reasonable planning of the home network layout can better meet the needs of the development of the times. Below we will talk about some specific issues from several aspects. ^[1]

Home network network structure

Generally speaking, as a home network, the number of connected computers is very small, and because the room is small, the wiring length is short. Therefore, there are two types of network topology to choose from: bus topology and star topology. The bus topology uses a cable as the backbone cable, and all devices on the network are connected to this trunk line with cables. ^[1]

The star topology is connected through a central node. This central node is the control node, and communication between any two nodes must pass through it. This topology usually uses a hub (HUP) as the central device to connect multiple computers. (Figure 2) ^[1]

It can be found that although the bus wiring topology has the simplest structure and does not require a hub (HUP), the relative cost is very low, but if we use a laptop and add a new computer, we will face great trouble. So a star topology is recommended. ^[1]

Selection of home network cables

After determining the star topology as the structure of our home network, we must focus on the issue of cable selection, which is often the most overlooked aspect for ordinary users. The main difference between shielded twisted pair and unshielded twisted pair is the addition of a metal shield sheath. The main function of this shielded sheath is to enhance its anti-interference ability, and at the same time it can improve its bandwidth to a certain extent. But because its price is more expensive than unshielded twisted pair, installation is also more difficult, coupled with the simple network structure and few equipment in the home, there is no need to use shielded twisted pair. ^[1]

In the EIA / TIA-568A standard, the recommended use is: 4 pairs of 100 Category 5 UTP (unshielded twisted pair). 4 pairs means that there are 4 twisted pairs in a wire sleeve, for a total of eight wires. Here to talk about the classification of unshielded twisted pair, American Electronics Industry Association (EIA) ^[1]

The wire material used for the five types of wires is 100 24AWG solid core wire (see Figure 3). AWG means: American Wire Gauge. 24 AWG refers to a copper wire with a diameter of 0.5 mm. Copper wires need an insulation layer. The most commonly used insulation layer is PVC. With the development of Gigabit Ethernet, there have been Category 5 and Category 6 cables, but they are not necessary in a home network environment, so they are not described. In the home network, the best choice currently is to use Category 5 cables. ^[1]

Home Network Cabling Specifications

Correct and standardized wiring is a necessary condition to ensure the normal operation of the network. Choosing high-quality cables does not mean that you have a high-quality network. Before introducing the wiring specifications, as a non-professional, you should have some understanding of the following important parameters affecting the network. ^[1]

(1) Near End Cross Talk-NEXT

Crosstalk refers to a tendency for a portion of a signal transmitted along a pair of wires to "leak" onto an adjacent pair of wires. The NEXT parameter of the connected crosstalk depends not only on the performance of the cable itself, but also the receiver along the connection path, including the final connector, and the technical level at which the connection was made (the cable at the connector is stripped to lose the twisted pair length) It also has a great impact on it. For unshielded twisted pair (UTP), near-end crosstalk is a key performance indicator. ^[1]

(2) Attenuation

Attenuation is a measure of signal loss along a line. The greater the attenuation of a twisted pair, the smaller the effective transmission distance of the signal. The effective transmission distance of a standard twisted pair is 100 meters (between the hub and the PC). ^[1]

(3) Noise

Noise in cables can cause problems in all communication systems. There are two types of noise to consider: impulse noise and continuous broadband noise. It should be recognized that incandescent lamps, electric motors, speakers and other electrical equipment are noise sources.

From the introduction above, it should be recognized that when planning the network wiring initially, pay attention to the distance from the noise source. The network cable cannot be placed in the same conduit with the power cable. The -569 standard specifies the distance between power lines below 480V and UTP, please refer to the following table: ^[1]

Home network cost estimation and equipment selection

To set up a home network, the equipment that may be used are: network card, network cable, RJ-45 plug (crystal head), hub and socket. Since the socket is easy to buy in the building material store and the price is relatively transparent, it is not described here. ^[1]

Let's talk about the price of the network card. Network cards are generally divided into 10M and 10M / 100M adaptive. High-end brands include 3com and Intel. Cheap brands include D-Link, TP-Link, Topstar, and Star and Lenovo. Our ordinary users have no need to choose high-end brand products, a common 10M network card is 40-50 yuan, 100M 60-70 yuan. Five types of four-core network cables have many brands in the market, and various counterfeit and inferior products are mixed. For example, brand names such as AMP have more fakes than genuine ones. It is recommended that you can choose the products of regular domestic manufacturers. Generally, the price of a box line (305 meters) is about 400 yuan. An eight-port 10M hub is about 200 yuan, and a 100M eight-port hub costs more than 600 yuan. In addition to the cost of the network card, the investment to set up a home LAN should not exceed 300 yuan, which is a very small part of the total cost of new house decoration. Therefore, I recommend that everyone, especially those who have just bought a new house to be decorated, should consider the network wiring in advance. . ^[1]

Home network formation characteristics

Development of home network technology drives market demand

The home in the future will be a networked and information-based home, with high-speed digital communication lines connected to the outside and a home server to control information appliances with different functions. The home network will be able to operate and control all the household equipment. When you are away, you can also control various equipment in the home through communication, such as opening automatic curtains or turning off the microwave. When you are working on the computer, you can use the computer A small window on the screen observes the image transmitted by the digital camera or camcorder installed on the door, confirms who is knocking on the door, and issues an alarm message if there is an abnormal situation; similarly, through the Internet, you can make various households Information transfer between devices. ^[1]

In the future, home office will become a trend, and home decoration will become a more comfortable office environment. People can use their laptops to maintain a connection with the company's computer network at any time, to carry out data communication anytime, anywhere, using printers, projectors, etc. Peripherals, without having to go through cables to maintain communication. ^[1]

Individuals will communicate with mobile phones and MP3 players through wireless headphones, make calls or listen to music. Digital cameras and digital video cameras will wirelessly communicate with digital photo frames and computers to display captured images. At the same time, they can be connected to printers and televisions wirelessly to enjoy wonderful sceneries.

With the help of short-range wireless communication products. People get more freedom of movement, and they don't have to face a mess of connecting lines. Eliminates many maintenance tasks. ^[1]

Competition of multiple technologies in home network affects the promotion of products

In the office environment of various foreign companies, the use of notebook computers connected with 802.11b antenna Ethernet technology has gradually become more popular, which has brought greater flexibility to people's work, allowing employees to connect with the entire company's computer network at any time. You don't have to choose a place with a wired network interface to go online. The popularity of personal computers in developed areas abroad has brought about the need for data exchange between computers in the home environment, computers and peripherals, such as printers, scanners and other devices. 802.11 wireless Ethernet can play an important role in it. ^[1]

With the popularity of various personal digital consumer products, such as MP3 players, digital cameras, and PDAs, the demand for communication between these digital consumer products and between them and computers is also very strong. The goal of Bluetooth short-range wireless communication technology is to provide communication guarantees in this regard. ^[1]

Traditional home appliances, such as televisions, air conditioners, washing machines, etc., also need wireless communication functions to communicate status, control information, and provide functions including remote access control. There are some wireless communication standardization organizations and products that apply to the control and transmission of status information of traditional home appliances, such as HomeRF, but most of them have not formed a large impact, and there are not many related products. ^[1]

Therefore, the short-range wireless communication technology used in the office or home is basically 802.11 and Bluetooth. 802.11 products should be mature and basically recognized by various manufacturers as the main wireless network technology standard in the future. Bluetooth products have just appeared, and the market and future development are not very obvious. However, considering that the main equipment in the home also includes appliances such as home appliances, and the communication between these devices also requires corresponding standardized technology. ^[1]

Domestic appliance companies represented by Changhong, Haier, and TCL are very optimistic about the networked market of information appliances and home appliances. They have also invested some efforts in market promotion and development, but are subject to restrictions that do not exist in related home wireless network standards. The product has not really entered the market. ^[1]

Home network separation is the foundation of technology

In fact, according to the demand for information transmission on the transmission belt, we can divide the family's demand for short-range wireless communication technology and products into two types. One is the audio, video stream information and high-speed data transmission that require large transmission bandwidth; The first is low-bandwidth control, status information, and low-speed data transmission. Considering the cost of supporting different needs and the acceptance of users, the entire home network is also structurally divided into two interconnected subnets. ^[1]

For high-speed video, audio and data streams, we use 802.11 as the underlying transmission technology to develop high-performance audio and video processing platforms and application-layer protocols for audio and video transmission, and eventually develop wireless audio and video products such as those used in Home theater wireless speakers, wireless TVs, wireless monitors, wireless printers, wireless scanners, wireless projectors, and other office products used for computer information transmission. At the same time, it supports standard TCP / IP protocols and builds on existing network protocols. Application protocols such as device discovery, service sharing, and device management. ^[1]

For low-speed control, status information, and data flow, we developed a set of low-level wireless transmission technologies, designed and developed high-level processing platforms and application-layer protocols, and finally developed a home wireless network system for the interaction of home appliances. Operation, home three meters / security / lighting and other equipment control and information transmission. ^[1]

The home information network is divided into different network segments according to the types of media and underlying protocols used when the devices and gateways are connected. The gateways are used to connect between different network segments. The gateway includes the home main network gateway and sub-gateways. The home main network gateway implements the connection conversion function between the home internal network and the external network, and the sub-gateway implements the connection conversion function between the home internal network segments. The network segment containing the home mainnet gateway is called the home mainnet, and the network segment connected to the mainnet through the sub-gateway is called the home subnet. Each gateway can provide other optional services in addition to the conversion function of connections between different types of networks. Devices on each subnet and main network provide various services within the home, which can be information devices that already have network functions, or devices that have network access capabilities after adding network function modules, or lower-level devices Subnet device. ^[1]

802.11/TCP/IP Home network is based on 802.11 / TCP / IP

The transmission technology and protocol specifications of the physical layer and data link layer of the home main network use Ethernet (including wired Ethernet and wireless Ethernet at various rates), and the network layer and transmission layer use the TCP / IP protocol. If wireless networking is used, it needs to be seamlessly connected with wired Ethernet and comply with relevant regulations of national radio management. ^[1]

The home mainnet and home control subnet realize the management of various devices in the home, including remote monitoring and various intelligent management. With remote control, remote query, centralized management and monitoring, home security defense, self-diagnosis of faults, self-feedback, remote maintenance, home energy management, etc. It should have the following features: ^[1]

a) Internet business: online shopping, telemedicine, browsing, sending and receiving E-mail, and online upgrading of home appliances;

b) Family information processing: document processing, etc .;

c) At least one device in the network handles functions such as memo, electronic dictionary, and electronic book reading;

d) Intelligent home management: remote control (computer control and telephone control), remote inquiry, centralized control, management and monitoring, home security defense, self-diagnosis of faults, self-feedback, remote maintenance, home energy management, remote centralized meter reading;

e) Personalized and schedule management;

f) home electronic entertainment;

g) Multimedia (AV) processing: remote timing TV program recording, etc. ^[1]

The home main network gateway is the core of the home information system structure. It can reduce the burden on other parts of the system and achieve interconnection with the WAN. The internal management of the local area network can play a leading role. The home main network gateway can receive communication signals from different external networks and transmit signals to various devices in the home through the home network. ^[1]

The home main network gateway should have two main functions:

-A physical interface that connects all external networks to the interior of the home and the internal network of the home to the outside;

Home users get various home services (including existing services and possible futures ^[1]

Home network upgrade network

Home network replace hub with switch

After installing ADSL, upgrade your home Linux LAN: Eliminate the hub and install a switch. If the difference between a switch and a hub is described in the simplest language, it should be the difference between intelligent and non-intelligent. ^[1]

A hub is a device that connects multiple computers. It can only play a role in signal amplification and transmission. It cannot process fragments in the signal, so it is very prone to errors during transmission. The switch can be regarded as an intelligent hub. In addition to all the features of the hub, it also has the functions of automatic addressing, switching, and processing. And in the transmission process, only the sending source and the receiving source work independently, and there is no relationship with other ports, so as to prevent data loss and improve throughput. From their working status, hubs are shared. In other words, when one port sends information to another port, other ports can no longer transmit information, and can only wait. In addition, the hub works in half-duplex, that is, it can only be unidirectional during the transmission process. The receiver must send the signal only after the information is sent from a sending source. The working principle of the switch is very different from that of the hub. Because each port of the switch can be regarded as an independent channel, it will not affect the transmission of other ports when it works. The switch works in full-duplex mode, so its data processing capacity has doubled virtually. ^[1]

Broadband sharing method for home network

Broadband sharing generally has three methods:

(1) Connect ADSL directly to the Up Link interface of the hub or switch (the first RJ-45 port on the left of the switch). Take this approach with caution, as you have encountered billing issues before. ^[1]

(2) Use Windows 2000 as a server to share broadband, but the higher computer hardware configuration required to run Windows 2000. ^[1]

(3) Use an older computer to install a Linux server to share the broadband. In fact, it is regarded as a NAT (Network Address Translation). ^[1]

After using ADSL, network security encountered a new problem. The importance of ADSL users' network security issues is much more important than those of users who access the Internet through modem dial-up. The reason lies in the "high-speed connection" of ADSL. When a saboteur attacks ordinary Modem dial-up network users, a slower connection reduces the efficiency of the saboteur, thereby improving their own security, and attentive users can feel the change in network speed. However, due to the extremely fast speed of ADSL, saboteur intrusion is not only highly efficient, but also very fast in carrying out sabotage actions. At the same time, the extremely high bandwidth makes users unable to detect the intrusion behavior. Using NAT can protect the system to a certain extent. ^[1]

Finally, I chose the third method, which is to install a Linux server using an older computer to share the broadband.

New network topology for home networks

In the new network topology, the positions of PC1 and PC3 are reversed. The upgraded PC1 acts as a server, and two network cards are installed, one connected to the ADSL Modem and one connected to the switch. That is, use it as a NAT (Network Address Transfer), so that the old machine can use its residual heat. It is well-known that what affects network speed is bandwidth, and CPU speed is not much affected. ^[1]

NAT can connect to the Internet, but does not allow all computers in the network to have a real Internet IP address. Through the NAT function, the legal Internet IP addresses applied for can be uniformly managed. When internal computers need to access the Internet, the fake IPs are dynamically or statically converted into legal IP addresses. In addition, if you do not want to let external network users know the internal structure of the network, you can isolate the internal network from the external Internet through NAT. ^[1]

After the upgrade, the IP address of PC1 is 192.168.1.1, the IP address of PC2 is 192.168.1.2, the IP address of PC3 is 192.168.1.3, the subnet mask is 255.255.255.0, and the gateway is 192.168.1.1.

At this point, the Linux home network upgrade is over. ^[1]

Home network network type

Home networking is also primarily the exclusive domain of technology enthusiastsmost homes don't need or can afford multiple computers. But now, a computer is not enough to meet the needs of many homes. In homes with multiple computers, home networking is often a necessity, not a technical toy. ^[1]

The two most popular types of home networks are wireless and Ethernet. In both types, routers perform most of the work and are responsible for controlling communication between connected devices. By connecting your router to a dial-up, DSL, or cable modem, you can also allow multiple computers to share an Internet connection. Many new routers combine wireless and Ethernet technologies and include hardware firewalls. The easiest and least expensive way to connect computers at home is to use a wireless network. This network uses radio waves instead of cables. Because no physical cables are used, this network is very flexible. For example, you can move your laptop between rooms without having to adjust the network cable or disconnect it. The disadvantage is that wireless connections are usually slower than Ethernet connections. ^[1]

Faster wireless network

Most home wireless networks use 802.11g wireless networking, which is capable of transmitting data at 54 megabits at 2.4 GHz. The newer wireless standard is 802.11n, which is faster and has a larger coverage area than 802.11g. However, the 802.11n standard is not the final version, and its early hardware failed to meet expectations during testing. If you want to establish a wireless network, you need a wireless router. The signal from the wireless router can travel about 30.5 meters in all directions, but the wall can interrupt the signal. Depending on the size and structure of your home and the coverage of your router, you may need to purchase a signal booster or repeater to achieve the coverage you need. ^[1]

A wireless adapter is also required for each computer you plan to connect to the network. You can also add printers and other devices to your network. Some new models of devices have built-in wireless communication capabilities, and you can use wireless Ethernet bridges to add them to devices without wireless capabilities. ^[1]

If you decide to establish a wireless network, you need to take steps to protect it-you probably won't want your neighbors to use your wireless signal for free. Wireless security options include:

Wired Equivalency Privacy (WEP)

WiFi Protected Access (WPA)

Media Access Control (MAC) address filtering

You can choose the method (or combination of methods) to use when setting up your wireless router.

You can choose the method (or combination of methods) to use when setting up your wireless router. ^[1]

Although wireless networks are simple and flexible, they are not for everyone. Some people just feel safer using a wired network, while others want to move large amounts of data quickly. In either case, wired Ethernet is the better choice. Ethernet is faster than wireless networks and can be very inexpensive. However, the cost of Ethernet cables is cumulative-the more computers on the network, the further away they are from each other, the more expensive it becomes. Also, unless you are building a new house and pre-installing Ethernet cables in the walls, you will see the cables spread around the home. ^[1]

If you plan to connect only two computers, you only need to install a network interface card (NIC) in each computer and connect a cable between the two computers. The most commonly used cable is Category 5 unshielded twisted pair (UTP). If you want to connect multiple computers or other devices, you need an additional device-an Ethernet router. You also need to connect each computer or device to the router with a cable. ^[1]

Home Network Cyber Security

There are hidden cyber security issues behind homes that set up wireless networks to access the Internet. A wireless network is more vulnerable to intrusion than a wired network, because the attacked computer and the attacked computer do not need a connection on the network cable device. As long as it is within the range of your wireless router or repeater, you can enter your internal network The accessed resources, if the data you transmit on the internal network is not encrypted, it is more likely that others will spy on your data privacy. ^[1]

1. Modify username and password (do not use default username and password)

Common home wireless networks access external networks through a wireless router or repeater. Usually these router or repeater device manufacturers provide a management page tool for the convenience of users to set up these devices to establish a wireless network. This page tool can be used to set the device's network address and account information. To ensure that only the device owner can use this management page tool, the device usually also has a login interface, and only users who enter the correct username and password can enter the management page. However, when the device is sold, the default username and password provided by the manufacturer for each model of the device are the same. Unfortunately, many home users will not modify the default username and password of the device after they buy these devices. This gives hackers a chance. They can easily find out the addresses of these devices with a simple scanning tool and try to log in to the management page with the default username and password. If they succeed, they will immediately take control of the router / switch. ^[1]

2. Use encryption

All wireless networks provide some form of encryption. As I mentioned before, as long as the attacking computer is within the effective range of the wireless router / repeater, then it has a great chance to access the wireless network. Once it can access the internal network, all transmissions in the network are transmitted. The data are transparent to him. If these data are not encrypted, hackers can use some packet sniffing tools to capture packets, analyze and sniff the privacy in them. Enable your wireless network encryption so that even if the data you transmit on the wireless network is intercepted, there is no way (or it is not that easy) to interpret it. Several encryption technologies already exist in wireless networks. Usually we use the strongest encryption technology. In addition, please note that if there are multiple wireless network devices in your network at the same time, the encryption technology of these devices should be the same. ^[1]

3 Modify the default service area identifier (SSID)

Usually each wireless network has a service area identifier (SSID). When wireless clients need to join the network, they need to have the same SSID, otherwise they will be "rejected." Usually router / repeater equipment manufacturers set a default SSID in their products. For example, the SSID of a linksys device is usually "linksys". If a network is not assigned an SSID or uses only the default SSID, then any wireless client can enter the network. This undoubtedly opens the door for hackers to invade the network. ^[1]

4 Disable SSID broadcast

In a wireless network, each routing device has a very important function, that is, service area identifier broadcast, that is, SSID broadcast. Originally, this feature was designed for commercial wireless networks where wireless network client traffic is particularly heavy. A wireless network with SSID broadcasting enabled, its routing device will automatically broadcast its SSID number to wireless network clients within its effective range. After receiving this SSID number, the wireless network client can use this SSID number to use this network. However, this feature has great security risks, as if it automatically opens the door for hackers who want to enter the network. In commercial networks, this function must be enabled at the expense of security in order to meet the frequently changing wireless network access points, but as a home wireless network, the network members are relatively fixed, so it is not necessary to enable this function. ^[1]

5. Set MAC address filtering

As we all know, basically every network contact device has a unique identifier called a physical address or MAC address, of course, wireless network devices are no exception. All routing devices such as routers / repeaters track the source MAC address of all packets passing through them. Generally, many of these devices provide operations on MAC addresses, so that we can prevent unauthorized devices (hosts, etc.) from accessing the network by establishing our own list of pass-through MAC addresses. But it is worth mentioning that this method is not absolutely effective, because we can easily modify the MAC address of our computer network card, I have an article dedicated to how to modify the MAC address. ^[1]

6. Assigning a static IP to a network device

As the DHCP service is becoming easier and easier to establish, many home wireless networks use the DHCP service to dynamically assign IPs to clients on the network. This leads to another security hazard, that is, the attacking end of the access network can easily obtain a valid IP through the DHCP service. However, in home networks with very fixed members, we can assign fixed IP addresses to network member devices, and then set a list of allowed device IP addresses on the router, which can effectively prevent illegal intrusion and protect your network. . ^[1]

7. Determine your location and hide your router or repeater

Devices such as wireless network routers or repeaters all transmit data through radio waves, and data transmission has a valid range. When your device's coverage is far beyond the range of your home, then you need to consider your network security, because in this case, hackers may easily log in to your home wireless network from outside your home. . In addition, if your neighbors also use wireless networks, then you also need to consider whether the coverage of your router or repeater will overlap with that of your neighbors. If they overlap, it will cause conflicts and affect your network transmission. Once this happens, you need to set a different frequency band (also called Channel) for your router or repeater from the neighbor network. According to your own home, choose a router or repeater with a suitable effective range and choose a location for it. Generally speaking, it is most suitable to place it in the middle of the home. ^[1]

Home Cyber Security Services

Home equipment security control services

When accessing and controlling a home device from a home external network, the control request must be over the Internet. But the Internet is not a secure area. So we designed a set of security control services for home facilities. This service establishes a secure channel between the mobile device and the home gateway. ^[1]

The Type field defines the type of the packet. The Sequence Number and Port are used to prevent MITM attacks. Integrity is used to check the integrity of the data. The operation procedure is as follows: First, the client sends an authentication packet to the server. After the server receives it, it authenticates the user. If the user is a registered user, the server returns the information to accept; otherwise it rejects. The client can continue to communicate with the server only after receiving the acceptance message. ^[1]

After the above procedure, all information transmitted between the home gateway and the PDA will be encrypted by the SEED block cipher Algorithm. With the exception of encryption, all encrypted data is accompanied by an Integrity value to ensure data integrity. Calculate the Integrity value using the MD5 hash algorithm. ^[1]

Stateful firewall

A firewall based on the state of transmission can detect and control network transmission. It protects the home network from Denial of Service (DoS) attacks, while also rejecting or receiving data from specific IP addresses and port numbers. ^[1]

The transmission state information collector collects communication information in the form of a state unit and analyzes it using statistical methods. The status unit includes the transmission mode and corresponding statistical information. The security policy manager establishes a security policy by using a security status chart. It reflects the status of all communications that appear on the network. The security state diagram changes the security policy according to the state transition of the transmission. The filtering rule generator converts the new security policy into filtering rules. The transport controller uses this rule to control the transport. When the state transition signal generator sends state transition information to the state table, the S1 state representing the transmission state will detect its own condition to see if it can accept the state transition signal. This engine can effectively manage network security to cope with rapidly changing transmission conditions. Administrators can save and analyze transmission information and security policy logs through a graphical interface. The transmission state-based firewall controls data transmission based on the IP address list in the home gateway and can reject or allow packets from specific IP addresses and ports specified by the user. ^[1]

Wireless LAN Security Services

WLAN security services [6] have the capabilities of intrusion detection [7] and access control. Intrusion detection systems include proxy collection and intrusion detection servers. Agents collect mobile sites that monitor and collect access point information and transmit data over wireless networks. The collected data is transmitted to the detection engine and converted into the format of audit data. ^[1]

Use 802.11 management data frames to monitor wireless networks [8]. The MAC data frame collector is responsible for collecting management frames, and the information extractor is responsible for extracting status information and statistical information. Status information is used to indicate the status of stations and access points. The statistical information represents the throughput and bit error rate of each channel, as well as the number of different types of frames and transmission information. The audit data generator then reconstructs the data using the audit data format. The audit data includes 7 fields. They are MAC address, current status, request count, separation count, non-authentication count, current serial number, serial number threshold, and so on. The detection engine detects intrusions through the Organizationally Unique Identifiers (OUI) list matching module and the serial number analysis module. ^[1]

Before an intruder can attack a WLAN, they need to forge a MAC address. The IEEE has assigned 6,278 prefixes to hardware manufacturers to specify the MAC address of the network card. By comparing OUIs and allocation lists, we were able to detect attackers who intruded by forging random MAC address prefixes. The IEEE recommends a method to accommodate fragmented addresses by using data frame ordering. In the sequence control field, 4 bits are used for the fragment address, and 12 bits are used for the sequence number. The sequence number field is a sequence counter. Each time a non-fragmented data frame is generated, the sequence counter is incremented by one. It starts at 0 and takes 4 096 to take the modulus. Unless the data frame is a fragment of a large packet, the fragment count is always 0. Hackers have no way to set this parameter to arbitrary values when cracking 802.11 data frames. When the module receives the first management data frame, it extracts the sequence number and saves it as a temporary variable. When the module receives the second frame, it compares it with the serial number of the first frame. If the sequence number of the second frame is not greater than the sequence number of the first frame, it will consider this to be an attack. Administrators can monitor the status of each site and access point. It can register trusted access points and use MAC address filters to manage those sites where households use wireless LAN resources. ^[1]

User Management Services

^[2] User management services provide users with authentication and authorization. We use role-based access control model [9] (RBAC) to implement. The RBAC model simplifies authorization management by assigning roles to access rights and users; instead of determining access rights based on users, users and permissions are assigned a role. The user's permission is both the permission of the role being assigned. Each home network user is assigned a role, such as using a father to represent administrators, children, and guests. Administrators can assign guests or children permissions to control home facilities and network resources. Every user who wants to access the home network from outside must have an ID and password. The administrator assigns each user the right to use home facilities by using an integrated management interface. ^[1]

Home network home network considerations

Since the widespread popularity of the Internet, scholars and technology enthusiasts have predicted that a new medium will turn homes into information-rich and active network centers. They predict that refrigerators will automatically monitor the shelf life of boxed milk and that homes will be twice as large as video centers. Three or four years ago, these were unimaginable and may never happen, because users think that new applications may cause more trouble than they bring. Over the past three years, technology has changed, companies such as Intel, Microsoft, and 3Com have fixed bugs, and companies such as Cisco and Ericsson have also tested the new technology to observe user reactions. ^[1]

The discovery of these companies may be just a dream though. However, people are willing to use easier-to-operate applications for a wider range of options and greater control over their home facilities. There is no doubt that the main broadband providers-cable and subscriber digital private line services-are very interested in home networking. In fact, for broadband providers, the need for simple applications is now strong enough. This includes not only the consideration of home network building hardware, but also the consideration of free network building. ^[1]

Home network construction hardware considerations

The hardware and software that enables home devices to share sound, video, and data can be placed in a separate unit or combined with a DSL modem, cable set-top box, PC, and other devices. This device can either transmit short-range wireless signals, or send data over telephones and wires, and eventually reach the devices and peripherals of computers throughout the user's home. ^[1]

Software developers such as Microsoft and Sun have developed protocols that enable devices ranging from refrigerators to laser printers to recognize each other. Over the past two years, semiconductor companies such as Broadcom and Lucent have introduced new integrated circuits to prepare for this type of network, taking advantage of the radio frequencies allocated for this purpose and the lines already installed in the home. The current mode is to transmit 10 Mbits of data per second through telephone lines or air; soon, the maximum speed is expected to reach 32 Mbps or higher, which is enough to simultaneously transmit some DVD-format audio or video signals. Most computer equipment and home application equipment manufacturers plan to start putting chips for home networking into production this year. If this trend continues, in three to five years, people in developed countries will suddenly find out one day that their home network has been built, although ten years ago they made televisions with remote control. ^[1]

Free network considerations

In order to understand the economic power of providing home network equipment to users for free, consider only the most basic and practical applications, that is, after the home network is established, people pay much less than if they did not have a home network. For example, a home network can easily link two or more home computers, but also requires the installation of an Ethernet card and a local area network. When all computers in the home can talk to each other, they can share printers, scanners and a single Internet connection, saving a lot of money for the home. Similarly, home networks allow a single set-top box to provide broadband cable services to several televisions, which reduces the cost of additional set-top boxes. It also provides at least one additional telephone line for the home. Home networks allow new phone jacks to be plugged into standard outlets, or allow for virtual fax numbers and alternate phone lines to be produced more cheaply. ^[1]

It is estimated that in the U.S. alone, home computer networks, cables for additional televisions, and additional telephone lines can save $ 14.7 billion in hardware, installation, and maintenance costs, which is only existing demand Average cost savings. In fact, the average American household can save at least $ 140 per year. After purchasing an independent home network box, users can immediately enjoy the benefits brought by home network construction. Broadband companies and DSL companies that manufacture border equipment are preparing to provide these benefits to users for free, and for them, adding appropriate hardware to a new set-top box or DSL modem is only a one-time cost. Given the potential savings of $ 140 per home, this installation will undoubtedly make overall economic efficiency more meaningful. In most developed countries, cable and DSL vendors are just beginning to ramp up new hardware installations. In the next 5 years, about 40% of American households will have a digital set-top box or DSL modem. ^[1]

To unravel the mystery of the home network, cable DSL vendors can implant new chips in new set-top boxes and modems, and then install equipment as planned. As a result, broadband providers have created an ideal channel for bringing home networks into large-scale markets. In order to raise funds for home networking, broadband companies must find a way to get some of the savings it saves. If all the saved costs flow into the user's pocket, the plan for home network construction will be temporarily put on hold until the user is willing to pay part of the cost. ^[1]

Home Network Home Network Development

Home network users are constantly turning to newer and faster home network connection technologies, including Gigabit Ethernet, 802.11n, and alternative wired technologies such as coaxial cables, power lines, and telephone lines. In 2008, 10/100 Ethernet was still the main technology used in home networks around the world. However, according to market research firm In-Stat, the number of 802.11x networks will exceed 10/100 Ethernet by the end of 2009. In addition, many Wi-Fi users have (or are) moving from 802.11b to the more powerful 802.11g, and some have even started upgrading from 802.11g to 802.11n draft-compatible products. "Another noteworthy trend is that among North American users, the proportion of home networks not only used for shared Internet access increased from 41.8% in 2008 to 49.7% in 2009," said Joyce Putscher, an analyst at In-Stat. But most consumers have yet to add consumer electronics devices to their networks, and there is still a gap between the personal computer and the consumer electronics world. "Recent research by In-Stat also draws the following conclusions: ^[1]

More than 300 million home networks will be installed worldwide in 2011.

In 2013, the global Gigabit Ethernet home network will more than quadruple to nearly 90 million.

The Asia / Pacific region will lead in Wi-Fi home network penetration by 2012.

Traditional networks consist of a backbone network and an access network. Home users are treated as a single network terminal (NT). After the emergence of a new home network, the network structure evolved into a tertiary structure. Moreover, the home network is connected to all kinds of electrical equipment, and its interface and control are far more complicated than other data networks. Therefore, achieving a unified home network is a very tedious and laborious task. There are two types of home network: wireless and wired. In the near future, standardization work has matured with technology and business operations. Wireless representative systems are: Bluetooth, HomeRF, and IrDA; wired representative systems are: HomePNA, USBII, and IEEE1394. Whether wireless or wired networks have the upper hand still needs to be tested by the market. ^[1]

As a home appliance, its initial function is to realize video on demand (VOD) by using cable television network and public telephone network. With the rapid development of software and hardware technology, its function has been greatly improved. As a home network control center, the set-top box must also integrate the functions of a gateway. It should contain the following units: ^[1]

(1) Central control unit. The core of this unit should be a high-performance and low-price CPU, which is responsible for various data processing and control and scheduling of other units.

(2) Network communication unit. This unit is responsible for connection with other devices in the home, and connection and communication with the local area network.

(3) Automatic control unit, this unit is responsible for the automatic control of lighting, air conditioning, fire alarm, gas leak alarm, security alarm and other electrical appliances.

(4) Data acquisition unit. This unit is responsible for the collection of household data such as water meters, electricity meters, gas meters, fire detectors, gas leak detectors, and anti-theft detectors.

Home network related functions

Home Network Video Services

This can be said to be the basic function of a set-top box (STB). It uses the set-top box to connect to the community service local area network and accepts services such as video on demand (VOD) and optional karaoke. After changing the situation where TV programs could only be passively received in the past, using video on demand functions, owners can actively choose their favorite programs to enjoy. And we no longer have to regret that we missed a program we like, because in the VOD system, we can completely control the broadcast of the program, and we can easily make it restart from the beginning. ^[1]

Home Network Information Collection

Collect various parameters of the owner's home operation, including measurement data of water meters, electricity meters, gas meters, heat meters, and room temperature and humidity. These data can be displayed on the high-definition digital TV in the home, or uploaded to the property management center for statistics and billing. The realization of automatic meter reading can improve the level of residential and property management. At the same time, residents can be free from the worry of meter reading by household managers. Property management companies or professional companies can also save a lot of manpower and material resources, improve work efficiency, and improve meter reading. Punctuality, reducing the occurrence of estimates, mistakes, and omissions. ^[1]

Start-stop management of home network appliances

Control the main electrical equipment such as air conditioners in the owner's home. The control method of household appliances is as follows: when the owner is outside, the dedicated phone number can be dialed through a dual-tone telephone or mobile phone. If there is no answer in the home, the centralized control machine automatically answers the call and provides the owner with voice information. Corresponding operation, remotely activate appliances such as air conditioners in the home, so that they can start working before the owner arrives at home to provide a comfortable environment. Similarly, start-stop management operations on home appliances can also be performed on the Internet. ^[1]

Home Network Information Service

Owners can understand various parameters of their home operations through the set-top box (STB), such as room temperature and humidity, various meter readings, and status of the controlled appliances. At the same time, they can conduct simple inquiries on various fees through the network. And can settle the charges through the SIC card interface on the set-top box (STB). The property management department can send payment notices and other related property management notices to owners through the community network and set-top box (STB). ^[1]

Home Network Application for Community Services

When the owner needs community services such as maintenance, transportation, and delivery, the direct-to-speech function provided by the set-top box can directly contact the community service center of the community. The specific operation is that as long as the owner picks up the handset on the centralized control machine and presses the community service button, the owner establishes a direct voice contact with the community service staff, and the owner speaks his own requirements. The community service center's workstation will automatically display the building number and room number of the requesting service owner and record it. ^[1]

Home network security precautions

Connected with anti-intrusion detectors such as door magnetic switches and dual-monitor probes. When an intrusion occurs, an alarm message is sent to the property management department and the district security department in a timely manner. The set-top box has an emergency call function. Inform the property and security authorities to take emergency measures. Safety is very important, and it is also the first consideration in home life. Intelligent residences, like intelligent buildings, should be able to detect fires as soon as possible and promptly report them; for leaks of flammable gases, they should also be detected and reported as early as possible to avoid further expansion and spread of hidden dangers, resulting in greater economic And loss of life and property. The reliability of the anti-theft system is also more and more urgently needed for people whose lives are increasingly improved. People can strengthen security measures through the intercom system and video intercom system in the house. In addition, detection methods to prevent the intrusion of thieves are connected to the security system of the residential community, which has increased the intensity of handling emergency situations. When the occupants are not at home, safety precautions can also be achieved, which increases people's sense of security and enables people to devote themselves to work with greater confidence. ^[1]

Intelligent control of home network

Intelligent housing requires the establishment of a comfortable and healthy environment. It can monitor the indoor temperature and humidity, and then control the operation of air conditioners to artificially simulate the breath of nature. Such as the fresh air, the breath of the wilderness, and the fragrance of flowers, so that people can experience and enjoy the beautiful situation in nature without leaving home. For family members with different age levels and health conditions, it can also automatically adjust the indoor environment according to different needs to achieve organic coordination. And control through the best control method to achieve the purpose of saving energy and reducing consumption. ^[1]

The above functions have often been formed into separate systems in the past in the construction of smart houses, and there is basically no information interaction between the systems, which causes repeated construction of many devices, which undoubtedly increases construction costs. The construction of the home network has realized the maximum sharing of information between home appliances, greatly reduced the cost of smart homes, and its functions have been improved. ^[1]

The core of smart house construction lies in the structure of the home network, and the complexity of the home lies in the variety of household appliances to which it is connected, and the interfaces are complex. And there is no unified standard for the communication and control interfaces of various electrical appliances. Therefore, the construction of a smart house is not something that a smart house developer can do alone. It is a huge system project that not only depends on the development of network interconnection technology. It also requires the participation of information appliance manufacturers to make home appliances comply with standards for digital devices in home networks. ^[1]

Home Network Voice Application

With the increase of terminals in digital home networks, users 'demands for voice applications have become more abundant, and users' call needs have evolved from simple phone calls to face-to-face video calls. At the same time, the terminals used by users are no longer limited to PSTN terminals and mobile terminals, but TVs and game terminals in homes are also expected to become call terminals. When the user is watching TV, when the phone rings, the user wants to be able to make a video call with the other party through the TV terminal. The user also wants to temporarily interrupt the game while using the game console for entertainment, and transfer the call to the game terminal to answer the call. . At the same time, the privacy requirements for the numbers of family members should also be met. When a family phone calls, the family members can easily distinguish which family member's phone is. In terms of home security monitoring, SIP phone doorbell and camera phone alarm linkage are also new applications for voice services. ^[1]

Implementation technology of voice application in home network

1.FMC

FMC in the home network field mainly means that home users can conveniently use mobile and fixed convergence services. The current Bluetooth, Wi-Fi, and IMS technologies are hotspot technologies for FMC in home network applications. ^[1]

In the application of the home network, the dual-mode terminal is connected to the gateway through Bluetooth or Wi-Fi, and the IP line or PSTN line connected by the gateway is used for talking. The bandwidth requirements of VoIP applications are not high. The current 802.11b can fully meet the Wi-Fi voice applications, but currently Wi-Fi mobile phones are facing two major problems of power consumption and security: most of the 802.11 components on the market currently cannot meet mobile The requirement of long standby time; in addition, the current process of securely configuring the wireless IP client is not smooth; meanwhile, the low latency of voice applications poses a challenge to the QoS of WLAN. ^[1]

In the field of IMS, VCC is the main technology for dual-mode end users to use FMC services. VCC technology (VoiceCallContinuous) is mainly used to seamlessly switch the voice between the external mobile domain and the home broadband domain when the user uses a multi-mode terminal. VCC technology is an extension of IMS and supports seamless voice switching control between 2G, R4 networks and IMS networks. VCC based on IMS architecture refers to the continuity of voice calls in the GSM / UMTSCS domain and the IMS domain. The main problem solved by VCC is handover, including handover from IMS domain to CS domain, and from CS domain to IMS domain. The VCC scheme will affect registration, originating calls, terminating calls, network domain selection, and supplementary services and billing. ^[1]

Softswitch

Users access softswitches through home gateways, and use VoIP services and video telephony services provided by softswitches. When the home gateway is in the IAD mode, a call is initiated by the home gateway proxy terminal phone, and user authentication is also completed by the home gateway proxy. An IP address is configured on the home gateway to interact with the softswitch system. The terminal phone does not participate in the IP protocol and is connected to the home gateway through a Layer 2 link. In addition, the home gateway may not participate in the VoIP registration and control functions, and only provides an IP channel; VoIP terminals in the home network all exist as SIP terminals for UI presentation and media stream processing. At this time, the home gateway needs to provide firewall and NAT functions. The firewall and NAT traversal method that uniformly regulates VoIP services can also be implemented by the application gateway provided by the home gateway with corresponding protocols. ^[1]

Home network voice channel construction steps

The construction of the current home network voice channel should be carried out step by step in accordance with the current network situation and user habits. The first phase of the VoIP voice service: mainly to provide users with a second "phone" (SIP soft terminal or hard terminal) and reliable and cheap voice services in the home. The soft terminal number can be bound to the home fixed-line number. , To achieve the same number of services, the soft terminal as an extension of the fixed telephone. Both soft and hard terminals should provide basic voice capabilities and supplementary service capabilities. For soft terminals, click-to-dial, instant message presentation, and multimedia capabilities are also provided. It is recommended that corresponding application servers be introduced to provide the above services. ^[1]

^[3] The second phase of VoIP voice services: to provide users with soft terminal services that roam within the local network. At this stage, the roaming management of VoIP services is performed through the IP address binding mechanism. Only roaming control is performed to distinguish whether the user is authorized to roam, and no roaming level is distinguished and charging is based on levels. For seamless switching of dual-mode terminals, it is recommended to implement it when the network has IMS conditions. ^[1]

In short, as the most common telecommunication service used by people, there are still many development opportunities in the home network environment. Operators seizing the opportunity of home network development can further promote the development of voice services. ^[1]

Home Network Home Network Significance

With the declining prices of computers and their accessories and the increasing popularity of the Internet, home networking has become a very practical fashion topic. Through home networking, not only can you save costs, enable many hardware devices to share multiple machines, make full use of existing resources, and make each computer no longer work alone, but become a whole existence. ^[1]

Choosing the type of home network: When setting up a home network, users need to consider choosing a suitable operating system and the actual networking structure. When selecting an operating system, consideration should be given to whether the access between the existing operating system and the selected operating system is convenient, whether the selected operating system is stable, whether it is convenient for network connection, and management. As far as the more common Windows operating system is concerned, users can try to choose a higher version of the operating system if the machine hardware configuration allows it. Because generally speaking, a higher version of the operating system is more stable than a lower version of the operating system, network functions are more powerful, and management and maintenance are more convenient. ^[1]

When choosing a network structure, users need to consider whether the selected network structure can maximize the effectiveness of the computers in the network, and whether it is easy to connect and maintain. Peer-to-peer network is a better choice for home networking. Using peer-to-peer network does not need to set up a special server to share resources such as applications, optical drives, printers, scanners, etc. with peer computers. Simple, easy to set up and maintain, it is a better choice for home networking. ^[4]

Gigabit Home Network

What is "Gigabit Home Network"? "Gigabit" refers to its efficient transmission speed, and "home network" refers to the wireless network connection technology it launched for homes. How is it different from other wireless network equipment on the existing market? ^[1]

The existing wireless communication products on the market are mainly WIFI series products. There are many WIFI devices. It is not a dedicated channel and it is easy to be interfered with. "We are equivalent to opening a separate highway to solve high-speed and high-definition requirements." SmartAir does not rely on any network. As long as it is installed between two electronic devices, a gigabit communication network is established for them, and it Plug and play for easy operation. ^[1]

In addition, the coverage of the "Gigabit Wireless HD Transceiver" is only ten meters. The reason why the coverage is so small is mainly to reduce the amount of radiation. "The WIFI signal can pass through even reinforced concrete, and it can transmit high definition. It must be terrible." Wang Junfeng explained that if the signal can pass through a hard, thick wall, its radiation volume must be very high, and then it will Bring great harm to the human body. "Gigabit wireless high-definition transceiver" radiation is very low, even less than 1% of WIFI, while ensuring a low amount of radiation while ensuring the viewing effect. ^[1]

In addition, no complicated device setting process is required, and the device can be used simply by connecting the device. All applications in the computer can be reflected on the TV screen, which is equivalent to a wireless external screen. The playback format is constantly updated on the Internet, and it is difficult to cover the set-top box. "Gigabit home network" devices have no restrictions on video playback formats. As long as they are available on the computer, they can be connected for playback and support HD. It is understood that this "gigabit home network" technology is the only one in China and only two or three in the world. It fills the gaps in important areas at home and makes the technically achieved targets far ahead in the world. ^[1]

Gigabit home networks have two directions, including wired Gigabit and wireless Gigabit. A series of related technology products will also be launched to implement wireless Blu-ray, wireless gaming and other functions. "Catch" computer characters to the TV within 100 milliseconds in a very short time, and players can watch the TV screen and enjoy swimming in racing and football games. Regardless of wireless gigabit or wired gigabit, there will be 100 billion-level market capacity in the future. Combining wireless gigabit and wired gigabit will also build a home gigabit network that will integrate all electronic devices in the home. It can also use this technology to achieve home cloud storage, and through a variety of electronic devices to the home cloud storage Extracting information from the media, not only takes advantage of the convenience of cloud technology, but also ensures the security of family data. ^[1]