What is the detailed technical standard of PON port?

Do you study computer in middle school?

I remember that high school textbooks were optional.

First of all, dial-up internet access is the most extensive.

Pstn (published switched telephone network) means "dial-up access", that is, surfing the Internet through ordinary telephone lines. Users can't answer the phone when surfing the Internet. At present, the highest rate is 56kbps, which has reached the channel capacity limit set by shannon theory. Although the speed is far from meeting the transmission requirements of broadband multimedia information, its biggest advantage is convenience, popularization and cheapness. There is a telephone line, plus a small "modem" of several hundred dollars.

At present, the charges are mainly prepaid, such as telecom 163, 169, China Unicom 165, Jitong 167, etc. Users can apply in the business halls of these companies, and they will get a special account and password to use these accounts to surf the Internet. When charging, it is charged according to the network fee+telephone fee. Generally, one hour is between 3 yuan and 5 yuan. Holidays and daily discount periods can be discounted. If you don't apply for an account, there are many direct dial accounts. For example, 263, its user name is "263" and its password is also "263". Direct internet access is relatively less favorable, and it is more suitable for users who have not been online for a long time. The fee is also charged according to the network fee+telephone fee. In addition, users can surf the Internet by purchasing a network card with an account number and password, such as 290 1 card of Telecom and 0/63 card of Unicom, and the Internet access fee is generally 4 yuan/hour. This method is conducive to controlling the cost of surfing the Internet, and is especially suitable for users who frequently travel online. In many places, even street stalls selling IC phone cards can be bought.

Second, it is correct for ISDN to call the Internet.

ISDN？ Integrated Services Digital Network (ISDN) is commonly known as single-wire communication. Its main feature is that users can answer the phone at will while surfing the internet, which is faster. Ordinary Modem need to wait 1-5 minutes to access, and the actual speed is 20-50 kbps, while ISDN access only needs 1-3 seconds, and the actual speed can reach 65438. Test data show that the speed of two-wire Internet access cannot be doubled, and narrow-band ISDN cannot meet high-quality broadband applications such as VOD.

But it is more expensive than telephone access. Users need special terminal equipment to use ISDN, which is mainly composed of network terminal NT 1 and ISDN adapter. ISDN adapters, like modems, are divided into internal and external types. Built-in cards are often called ISDN built-in cards or ISDN adapter cards. The external ISDN adapter is called TA. The price of ISDN built-in card is around 300 ~ 400 yuan, and the TA is around 1000 yuan. In addition, its monthly rental fee is 0.5 times that of 65438+ ordinary telephone, that is, 32.4 yuan. The fee is charged according to the internet fee+call fee, and the one-hour internet access fee can be twice as high as that of ordinary dial-up internet access.

Third, ADSL one's broadband.

ADSL？ Asymmetric Digital Subscriber Loop (ADSL) is a technology that can provide broadband data services through ordinary telephone lines. ADSL supports the uplink rate of 640 kbps- 1 Mbps and the downlink rate of 1 Mbps-8 Mbps, and the effective transmission distance is within the range of 3-5 kilometers. In the ADSL access scheme, each user has a separate line connected to the ADSL office, and the data transmission bandwidth is exclusively enjoyed by each user. Compared with the first two internet access methods, ADSL is always online without dialing, and the actual speed can reach 400-5 12 kbps, which is much faster.

Its initial investment cost is high and it needs a network card. Generally, the initial installation fee is about 300 yuan, and the Internet access fee is less. At present, monthly subscription is generally used for a limited time, ranging from 49 yuan to 380 yuan according to the limited time. Users can open accounts in various business halls, and professional technicians will come to the door to install and debug.

Fourth, DDN is mainly oriented to units.

DDN is the abbreviation of English DigitalDataNetwork. The communication rate of DDN can be in N×64kbps according to the user's demand? N = 1-32。 Of course, the faster the speed, the higher the rental fee. Users need to apply for opening an account when renting DDN business. Generally, DDN can be charged on a monthly basis or according to the flow, which is different from the on-time charging method of ordinary users dialing Internet. The rental fee of DDN is relatively expensive, mainly for companies that need comprehensive use, such as group companies. DDN charges different bandwidth fees according to different rates. For example, to apply for a local DDN line of 128kbps in China Telecom, the monthly fee is about 1000 yuan.

Verb (abbreviation for verb) VDSL faster broadband

VDSL is faster than ADSL. Using VDSL, the maximum download rate can reach 55Mbps and the upload rate can reach 2.3Mbps in a short distance. VDSL uses a pair of copper wires, and the effective transmission distance can exceed1000 m.. However, VDSL technology is still in the early stage of development, remote applications still need to be tested, and the popularization of endpoint devices will take some time.

6. Cable modems depend on cables.

Cable-Modem is an ultra-high-speed modem, which has only been tried in recent two years. It uses ready-made cable TV? It is a mature technology to transmit data through cable TV network. With the development of cable TV network and the continuous improvement of people's quality of life, accessing the Internet through CableModem has become a high-speed access mode that attracts more and more attention from the industry.

Cable-Modem connection modes can be divided into two types: symmetric rate type and asymmetric rate type. The data upload rate and data download rate of the former are the same, both between 500 kbps and 2 Mbps; The data upload rate of the latter is between 500 kbps and 10 Mbps, and the data download rate is between 2 Mbps and 40 Mbps.

Because of the * * * sharing structure, with the increase of users, the personal access rate will decrease and the security is not good. The most important thing is that the radio and television system does not have its own internet export, and the wired networks in various places are self-contained, and there is no networking to form a whole. They all rent Internet outlets of Telecom, Netcom and Unicom in various places.

Seven, PON fttp

PON (Passive Optical Network) technology is a point-to-multipoint optical fiber transmission and access technology, which adopts broadcast mode in downlink and time division multiple access mode in uplink. PON includes ATM-PON (ATM-based passive optical network) and Ethernet-PON (Ethernet-based passive optical network). The bandwidth used by each user of PON can be flexibly divided from 64kbps to 155Mbps, and users accessing an OLT can enjoy 155Mbps.

Eight, LMDS wireless communication

This is a wireless access technology that can be used for residential broadband access at present. The bandwidth of each end user can reach 25Mbps. But its total bandwidth capacity is 600Mbps, and users under each base station enjoy bandwidth. Therefore, if a base station has more users, the bandwidth allocated to each user is very small.

The "Mobile Office" that China Netcom is trying to run is a wireless broadband access mode, which meets the needs of mobile office. However, like mobile phones, it is necessary to have base station receiving equipment within a certain distance around users' internet access equipment, so it is obviously unrealistic to lay base stations on a large scale. China Netcom has only made some attempts in public gathering places such as hotels and airports.

Nine, local area network residential broadband

LAN mode access is to use Ethernet technology, using optical cable+twisted pair to comprehensively wire the community. Therefore, it is called residential broadband, because this method is the most widely used in all cells with broadband access. The user's home computer can access the Internet through five jumpers and five modules on the wall.

The LAN can provide * * * bandwidth above 10M, and can be upgraded to 100M according to user's requirements. At present, the operators engaged in this mode in the market mainly include Great Wall Broadband, Ranbo Wan Wei, China Telecom and local radio and television stations.

The disadvantage is that the private line rate is often very low, which restricts the development of LAN mode, and the security of users in the same exchange is also worth considering. The user's account opening fee is about 500 yuan, and the monthly internet access fee (monthly) 100- 150 yuan.

Detailed enough ~ hehe