With the development and popularization of Internet broadband applications, broadband access technology is constantly innovating, people's demand for access bandwidth is also constantly improving, broadband access technology is also developing with each passing day, and the market competition is becoming increasingly fierce. The rapid changes in the market have given birth to the development and application of FTTH access technology, and we think FTTH is coming to us.

1.FTTH can provide ultra-high bandwidth.

As we all know, the current broadband access technologies, such as ADSL, LAN access based on Category 5 cable, cable modem, etc., can only provide access bandwidth below 10M, while FTTH access network with optical fiber as transmission medium can theoretically provide unlimited bandwidth for users, and mature FTTH technology can easily provide users with any bandwidth in the range of 0 to1g..

2. There are FTTH solutions with low cost and mature technology.

Driven by market demand, FTTH technology has made great progress in recent years. Optical access network technology based on Ethernet peer-to-peer network topology has been widely used in FTTH, especially in North America, Japan and South Korea, because of its mature technology and low cost. FTTH solution based on Ethernet follows mature Ethernet technology. Technically, its advantage is that it can easily provide the bandwidth of 100M or 1G, and seamlessly link with the existing computer network. At the operation and maintenance level, it has the advantages of simple network structure and low construction and operation and maintenance costs. At the application and business level, it has the ability to support all broadband applications on the Internet at present, and support various business capabilities of data, voice and video broadcasting.

Besides mature point-to-point FTTH technology based on Ethernet, broadband access technology of passive optical network (PON) based on Ethernet point-to-multipoint network topology has been developed in recent years. However, because its standard has not been unified and widely used, the equipment cost is still high. However, people in the industry agree that PON broadband access technology based on Ethernet is also an ideal FTTH technology. With the promulgation of its technical standard and the sharp drop of equipment price, it will supplement FTTH access technology based on Ethernet peer-to-peer network topology and be widely used in FTTH.

As of June 2003, there were 980,000 FTTH users in the United States and 460,000 in Japan. It is predicted that FTTH users in the United States and Japan will increase by more than 200% every year in the next few years.

3. The competition of operators needs FTTH.

Since the day when China Telecom's exclusive monopoly on the domestic telecom market was broken, the competition in the domestic telecom industry has become increasingly fierce, especially in the Internet broadband access market. Enterprise participating in that broadband access market competition include almost all telecom operator at present. Among them, the traditional telecom operators are China Telecom and China Unicom, the emerging telecom operators are China Netcom and Tietong, and the resident network operators are Great Wall Broadband and Juyou Network.

Table 1.2. 1 shows the development status and prospects of major broadband access technologies in China. As can be seen from the table, LAN access technology based on five types of lines is difficult to develop on a large scale because of its technical and networking defects; Due to the unbalanced development of China's cable TV network, obvious industry monopoly and dense residential market, the Cable Modem broadband access technology has been developing poorly, and it is expected that its future development will continue to be limited. VDSL is an access technology with higher bandwidth than ADSL, but it has not been applied in China at present because of its immature technology and short access distance, but it may be used in the near future. ADSL is the most popular and best developed broadband access technology in China. Although ADSL has some shortcomings, such as limited bandwidth and low network outgoing rate, it will be further developed in the future with the advantages of mature technology and low network construction cost. ADSL and VDSL will make China Telecom, which has been connected to the telephone line, dominate the broadband access market in the future. Obviously. In order to break the monopoly of China Telecom ADSL on broadband access market, other operators have to choose a new and more competitive access mode to compete with it, that is FTTH!

4. The competition of real estate developers needs FTTH.

At present, the competition in the domestic real estate market is very fierce. Real estate developers often use the most advanced broadband access technology in residential areas or buildings to creatively package commercial housing, such as using integrated wiring buildings and intelligent residential areas a few years ago, and then using the so-called broadband residential areas, broadband internet access and other concepts for speculation. It can be predicted that with the maturity of all-optical access network technology and the gradual formation of the market, real estate developers, as one of the main users of broadband access technology, will actively turn from the transition scheme of existing broadband access technology to the final solution of all-optical access network, and make the next round of speculation on the new concept of real estate market.

5. FTTH is needed to provide users with various services.

With the rapid development of communication technology and information explosion today, people have enjoyed a variety of communication technologies and information sources, and people naturally need broadband communication access technology that can support a variety of communication services. Undoubtedly, FTTH broadband access technology with optical fiber as transmission medium can meet this demand. As mentioned above, fiber-optic broadband access technology is the ultimate and full-service solution of access network, which breaks through the bottleneck of broadband communication at present, and realizes the integration of computer internet, telephone network and cable TV network in access network at the same time, providing data, voice and video services.

6. Cheap optical cable promotes FTTH

In recent years, due to the improvement of optical fiber drawing technology, the price of optical cable has dropped again and again. At present, the outdoor optical cable per core per kilometer is lower than 400 yuan RMB, lower than the price of copper cable and V cable. Cheap optical cable undoubtedly provides greater possibilities for realizing low-cost FTTH broadband access.

To sum up, the time is ripe for laying optical cables and providing fiber-optic broadband access in the access network on a large scale! Moreover, from the perspective of broadband access technology and market development trend, whoever lays FTTH optical cable today will have the future of communication.

Second, the comparison of EPON and GPON prospects

EPON and GPON have their own technical positioning, and there is no strict distinction between advantages and disadvantages; But at present, the technical maturity and commercialization of EPON have far exceeded GPON.

Indeed, judging from the development of FTTx in China and even the whole Asia-Pacific region, EPON has become the mainstream choice to realize FTTx.

The development trend of EPON is gratifying.

In China, EPON has made remarkable achievements in commercialization and practical performance.

In terms of commercialization, EPON is expanding to the whole country. According to the reporter's understanding, after 20,000 households in Beijing, Shanghai, Hubei, Guangdong and other places completed the EPON FTTH pilot, China Telecom believed that the commercialization of EPON technology was becoming more and more mature, and at the end of 2006, a new EPON pilot scheme was launched, allowing provinces and cities to carry out the pilot after filing at the headquarters.

At the same time, EPON equipment manufacturers are rapidly following the commercialization process of EPON in China market. At the 10th ITU World Telecommunication Exhibition held in Hongkong not long ago, PMC-Sierra introduced the first end-to-end EPON chip scheme, and took the lead in designing the new data encryption and decryption algorithm, service quality and classification protocol standard of China Telecom Group, which is very suitable for large-scale deployment in China market.

In terms of actual performance, EPON has been able to meet more technical requirements better and better by adding some enhanced functions. The reporter learned from Beiyou Optical Communication Center and Optical Network Research Office that traditionally, EPON's support for TDM services is weak, but at present, EPON equipment manufacturers can generally meet the transmission requirements of TDM services in different environments by adopting various patented technologies of TDMoverEthernet and using various PWE3 devices on ordinary Ethernet. By attaching enhanced features to devices, EPON has been able to compete with most functions defined in GPON standards in terms of QoS and OAM.

It can be said that the easy deployment of EPON technology itself and its inheritance to Ethernet determine its strong vitality. EPON inherits the fine tradition of "simplicity is beauty" of Ethernet, and tries to make small changes and increase functions within the framework of technical standards. EPON and its technical alliance can be said to have been in the benign development of mutual promotion. Some experts pointed out that GPON in the United States and Europe adopts APON/BPON in line with its own technological evolution path, and can realize FTTx-scale EPON in the Asia-Pacific region to meet the needs of the Asia-Pacific market.

It can be predicted that EPON, which inherits Ethernet technology, will play a great role in FTTx today when packet-switched networks become the mainstream.

GPON is caught in a cost bottleneck.

Compared with EPON in full swing, GPON has always been subject to the high cost brought by its own technical complexity. The cost is closely related to the commercialization of technical products. The cost of core chip and optical transceiver module in PON system largely determines the cost of the whole PON system.

In terms of chips, Wei Xu told reporters that there are no real commercial chips in GPON at present, and most of them are test chips. GPON chip needs a new packaging format, and the "technical threshold" is high, so it is difficult to reduce the chip cost. Moreover, most of the existing GPON products are aimed at the demand of the North American market, and there is no in-depth research on the China market. GPON products that truly meet the demand of the China market have not yet come out. There is a big gap between the cost of GPON chip and that of EPON chip.

The cost of optical module is a bottleneck problem. Gao Peng, marketing director of Fiberhome Communications, told reporters that GPON's high requirements for technical indicators of optical module equipment will also become a bottleneck problem for its equipment suppliers to reduce costs, "which cannot be solved simply by increasing the number".

According to the data of optical module manufacturers, GPON optical module requires high power of ONU transmitter and sensitivity of OLT receiver, so it can only use DFB transmitter and APD receiver, and their cost is almost six times that of traditional FP transmitter and PIN receiver used in EPON module.

In addition, the optical module of GPON needs to meet the good burst synchronization index, which requires higher drivers and front and rear power amplifier chips in the module, and also needs to meet the power budget of three ODN. These factors, * * * isomorphism has become an insurmountable obstacle in the process of reducing the cost of GPON optical module.

GPON may become a replacement.

There is no doubt about the maturity and feasibility of EPON technology in the industry, but it cannot be considered that GPON has no foothold in the market. Regardless of the cost factor, GPON has obvious theoretical advantages in downlink speed, line efficiency, security, supported business types, network management capabilities and many other aspects. Many analysts believe that if the prospect of IPTV in China is further clarified, the market demand for downlink bandwidth and multi-service bearer of access network will be further expanded, which will play a huge role in pulling GPON, leading to the maturity of GPON industry alliance and the reduction of equipment cost.

At present, many domestic communication equipment manufacturers focus on EPON and GPON, but at the same time they are making other preparations for GPON. In this regard, Wei Xu said that GPON's excellent carrying capacity for operators' various services, especially voice services, will always be its advantage. He said that the technical maturity and large-scale commercialization of EPON have determined that EPON has become the dominant technology in FTTx, but most manufacturers do not intend to give up making GPON products. When making FTTx products and solutions, they pay more attention to the scalability of EPON optical access network system. For example, Changguang's EPON products can smoothly transition to GPON system by replacing only one board device.

In terms of operators, although the maturity of EPON has been clearly recognized, the attitude towards GPON is not exclusive. From early July to late August, China Telecom Group Company conducted the first functional verification test of domestic GPON equipment in Shanghai. Vendors participating in the test include Huawei.

Alcatel, Siemens and other communication equipment providers, most of the test equipment has reached satisfactory performance indicators. Of course, these devices are still in the testing stage, which is far from the commercial standard of mass production.

The advantages of EPON are as follows:

(1) Low cost, simple maintenance, easy expansion and easy upgrade. EPON structure does not need power supply and electronic components in the transmission process, so it is simple to lay and basically does not need maintenance, saving a lot of long-term operating costs and management costs. EPON system occupies less local resources, has high modularity, low initial investment, easy expansion and high return on investment. EPON system is a future-oriented technology. Most EPON systems are multi-service platforms, which is a good choice for the transition to all-IP networks.

(2) Providing very high bandwidth. At present, EPON can provide the bandwidth of 1.25 GB/s with symmetrical uplink and downlink, which can be upgraded to 10 GB/s with the development of Ethernet technology.

(3) The service scope is large. As a point-to-multipoint network, EPON uses fan-out structure to save CO resources and provide services for a large number of users.

(4) Flexible bandwidth allocation and guaranteed service. There is a complete bandwidth allocation and guarantee system.

According to expert analysis, EPON and GPON are not incompatible and are likely to coexist. For large-scale access customers with high bandwidth, multi-service and security requirements, FTTx realized by GPON naturally has more market. At present, EPON has become the mainstream in the domestic FTTx field. With the cost reduction, GPON will become a supplement and upgrade option for some EPON markets in the future.