Future Trend of Broadband Access Technology

In the future, the new direction of broadband access technology is constantly being compared. Today, we focus on the basic status, password settings, and IP address settings in the new direction of broadband access technology. For access-related settings, please refer to the relevant documentation, this article will not be detailed.

Access Network (AN) is a new concept put forward internationally in recent years. It not only includes user-line transmission systems and reusable devices, but also includes digital cross-connection devices and user/Network interface devices. In G.963, the latest recommendation of the ITU-T 13th Research Group, the access network is defined as an implementation system between the local switch (LE) and the client device (TE, the purpose is to integrate the needs of local exchange bureaus, user loops, and terminal devices into business nodes through a limited standardized interface.

The introduction of the access network has brought about new changes to the communication network, and the structure of the entire communication network has undergone fundamental changes. Due to transmission losses, transmission bandwidth, and noise restrictions, the current copper access network is increasingly difficult to meet the needs of new telecom business development, and gradually become the bottleneck of the broadband integrated business digital network. As a link between the Exchange Board and the user terminal, the digitalization and broadband of the access network have naturally been put on the agenda and become one of the focal points of the Development of telecom networks.

Recently, with the decline in technical costs, the increasingly open telecommunications market, and the explosive growth of data services represented by IP addresses, network bandwidth and capacity have become a hot topic and a shortage of commodities. The backbone networks of the developed countries represented by the United States are moving towards ultra-high speed and ultra-large capacity development. Wavelength Division Multiplexing Systems with a capacity of up to 160 Gbps (16 × 10 Gbps) have been put into use. At the same time, in order to adapt to this new situation, the new direction of Broadband Access Technology for access networks also shows a new development trend.

New Copper Connection Technology

We are already familiar with HDSL and ADSL technologies. Next we will focus on the new directions of several other copper Broadband Access Technologies.

VDSL (very high bit rate digital user line) Technology

With DMT line codes, the uplink/downlink transmission rate of twisted pair wires can be extended to 25 M ~ 52 Mbps, which can accommodate 6 ~ 12 4 Mbps MPEG-2 signal, at the same time, its allowable uplink rate is 1.5 Mbps, the transmission distance is 300 ~ About 1000 meters.

CDSL (User DSL access) Technology

CDSLConsumer DSL) is a registered trademark version of DSL. It is slower than ADSL, And the downlink speed is 1 Mbps, And the uplink line may be less ). However, it also has its own advantages. It does not need to install the "shard" on the client ".

FreeDSL (free DSL access) Technology

This is not so much a technology as a service. FreeDSL refers to the provision of free ADSL hardware and installation, and no service fee is collected every month.

G. Lite or DSL Lite Broadband Access Technology New Direction

G. lite is also called DSL Lite, non-shard ADSL, or general ADSL). It is a slow ADSL, and it does not need to separate the lines on the user end, but the telephone company remotely divides the lines for the user. G. Lite, officially referred to as ITU-T standard G-992.2, provides a range from 1.544 M ~ The downstream speed of 6 Mbps, and from 128 kb ~ The uplink rate of 384kbps. G. Lite is expected to become the most widely deployed DSL technology.

IDSL (New Direction of ISDN-DSL Broadband Access Technology

IDSLISDN-DSL) This call is somewhat inappropriate, because its speed is closer to the ISDN's kbps data rate and service, and far from the faster ADSL.

RADSL (New Direction of rate-adaptive DSL Broadband Access Technology

In this technology, the software can determine the signal transmission rate on the telephone line of a specific customer and adjust the transmission rate accordingly. Westell's FlexCap2 system uses RADSL to submit from 640 kb ~ The downlink rate of 22 Mbps and the uplink rate from 272kbps to 1.088Mbps.

UDSL (one-way DSL access) Technology

UDSL is a one-way HDSL version proposed by a European company.

New Directions of Wireless Broadband Access Technology

Wireless Access refers to the new direction of broadband access technology from exchange nodes to user terminals. Wireless access technology can be divided into mobile access and fixed access. Mobile Wireless Access networks include cellular mobile phone networks, wireless call seeking networks, cordless phone networks, cluster telephone networks, global satellite mobile communication networks, and personal communication networks. They are one of the most active areas in today's communication industry. Wireless User loop (WLL) is gradually evolving from a simulated system to a digital system.

Wireless access can be divided into mobile access and fixed access. Mobile access can be divided into two types: high speed and low speed. High-speed mobile access is generally available in cellular systems, satellite mobile communication systems, and cluster systems. Low-speed access systems can use PGN micro-cells and micro-cells, such as cdma will, PACS, and PHS. Fixed access refers to wireless access from switching nodes to fixed user terminals. It is actually a wireless extension of the PSTN/ISDN network.

The goal is to provide users with transparent PSTN/ISDN services. the terminals of the Fixed Wireless Access system do not include or only contain limited mobility. The access methods include microwave one-point multi-access, fixed applications for mobile access in cellular areas, wireless user loops, and satellite VSAT networks. The Fixed Wireless Access system mainly provides narrowband services, which are basically telephone services.

There are three main New Directions of the fixed wireless broadband access technology, namely, the multi-channel Multi-Point Distribution Service (MMDS) and the live broadcast satellite system (DBS) and local Multi-Point Distribution Service (LMDS) that is being tested in the field ). The first two are well-known, while LMDS is just emerging and has recently become a hot emerging broadband wireless access technology.

In general, broadband fixed wireless access technology represents a new trend that cannot be ignored in the new direction of broadband access technology. It is not only fast, easy to maintain, but also low in cost when users are relatively confidential, in addition, it has changed the traditional concept of local telecom services and is most suitable for effective competition between new telecom competitors and traditional telecom companies and cable TV companies, it can also be used as an important supplement to the wired access of telecom companies.

New Directions of optical fiber broadband access technology

An optical fiber user network refers to an access network that uses optical fiber as the transmission media completely between the local terminal and the user. There are many network fiber-optic solutions for users, including optical fiber to the roadside (FTTC), optical fiber to the residential area (FTTZ), optical fiber to the Office (FTTO), optical fiber to the floor (FTTF) optical fiber to the home (FTTH ). However, no matter what field of application, fiber-to-the-home must be implemented to meet the objective needs of high-speed broadband services and two-way broadband services.

The main technology of the optical fiber user network is the optical fiber transmission technology. At present, the multiplexing technology of optical fiber transmission has developed rapidly, and most of them are in practical use. The most widely used Multiplexing technologies include TDM, WDM, OFDM, and CDM.

New Directions of hybrid broadband access technology

At present, China's access networks are still dominated by traditional copper lines, and optical fiber access devices are used in a few urban areas. Most of the network topologies of access networks in urban areas are star-or bus-oriented, and the transmission media is dominated by local cable and twisted pair wires. Therefore, it is of great practical significance to study the transition from a hybrid fiber-optic coaxial network (HFCs) to a fiber-optic network in China.

The hybrid fiber-optic coaxial network technology enables telephone companies to quickly provide broadband services. In a coverage area of around 500 optical nodes, the service can provide 60 analog radio and television channels, at least two telephones per household, and data services with a rate of at least 10 Mbps. In the future, use its 550 MHz ~ The 200 MHz spectrum also provides at least MPEG-2 of on-demand TV services and other two-way telecommunications services.

An important trend in the development of Wired Access networks is the integration of FTTC and HFCs, which leads to the development of FTTC. Recently, the access network has proposed a new networking solution: FTTC + HFC. The FTTC + hfc-trunk system transmits digital (bidirectional) and analog signals by means of optical fiber cables. After the two types of information are restored to their respective baseband signals by the optical network units on the roadside, voice signals are sent to users through twisted pair wires, while digital and analog video signals are sent to users through Copper axis cables.