HDSL (High speed Digital Subscriber Line)

HDSL (High speed Digital Subscriber Line) - family development is XDSL early, apply more extensive, using an echo suppression, adaptive filter and high-speed Digital processing technology, using 2B1Q coding, using two twisted-pair realize the data transmission, and two-way symmetric transmission rate 2048Kbps / 1544Kbps (T1 / E1 Line), each for transmission rate for 1168Kbit/s, use 24AWG (Gauge Wire as U.S. cable procedures) twisted-pair cable (equivalent to 0.51 mm) when the transmission distance can achieve 3.4 KM, can provide standard T1 / E1 interfaces and v. 35 interface.

HDSL features:

Second-ranking 'symmetrical

Second-ranking over to pairs cooper

Second-ranking support 64Kbps, N = N x 1-32

Second-ranking 2B1Q encoding

Second-ranking compared with traditional T1 / E1 equipment, more economy

HDSL faults:

Second-ranking norms are too simple, if producers self-developed will influence the interoperability

Second-ranking 2B1Q coding, limit the transmission distance

Second-ranking cannot voice and data simultaneously transmit

HDSL2

HDSL technology developed on the basis of the second generation of high speed digital subscriber line, called HDSL2. Can in a single twisted-pair copper to achieve the T1 / E1 transmission, the application prospect of more widely

In order to solve the defects of HDSL, ANSI (North America standardization organization) released HDSL2 technology to realize the equipment standardization, solve problems interoperability. It can use CAP coding, increased the transmission distance, and can allow voice and data with preach, can use a pair or two for twisted-pair cable, using OPTIS modulation technology, string words interference performance below 5 db. In the United States, HDSL2 solve traditional telecommunication companies to adopt high demand area copper wire, and a shortage of new communication companies to HDSL2 interest is it can save cost. In addition, HDSL2 can T released with itu-t G.S HDSL standards compliant. Because ETSI (Europe standardization organizations) delayed HDSL2 through, delayed it in the world of promotion, at present, the support of this standard products in the Chinese market use less.

HDSL4

4th generation HDSL (high data bitrate digital subscriber line), is a higher version of the HDSL2, it through the use of two lines (and therefore, 4 wire) than HDSL or more than about 30% of the HDSL2 farther distance, however HDSL2 USES a pair of wire.

HDSL the main application of:

Telecom operators to provide customer 2M DDN

Digital switches connected

High bandwidth video conference

Distance teaching

Cellular phone base stations connection

Special network modeling

The enterprise internal network construction

Below actual case about HDSL applications:

Using a favorable long-distance 2M line network

Application of two, LAN outspread

HDSL (High speed Digital Subscriber Line) - family development is XDSL early, apply more extensive, using an echo suppression, adaptive filter and high-speed Digital processing technology, using 2B1Q coding, using two twisted-pair realize the data transmission, and two-way symmetric transmission rate 2048Kbps / 1544Kbps (T1 / E1 Line), each for transmission rate for 1168Kbit/s, use 24AWG (Gauge Wire as U.S. cable procedures) twisted-pair cable (equivalent to 0.51 mm) when the transmission distance can achieve 3.4 KM, can provide standard T1 / E1 interfaces and v. 35 interface.HDSL features:Second-ranking 'symmetricalSecond-ranking over to pairs cooperSecond-ranking support 64Kbps, N = N x 1-32Second-ranking 2B1Q encodingSecond-ranking compared with traditional T1 / E1 equipment, more economyHDSL faults:Second-ranking norms are too simple, if producers self-developed will influence the interoperabilitySecond-ranking 2B1Q coding, limit the transmission distanceSecond-ranking cannot voice and data simultaneously transmitHDSL2HDSL technology developed on the basis of the second generation of high speed digital subscriber line, called HDSL2. Can in a single twisted-pair copper to achieve the T1 / E1 transmission, the application prospect of more widelyIn order to solve the defects of HDSL, ANSI (North America standardization organization) released HDSL2 technology to realize the equipment standardization, solve problems interoperability. It can use CAP coding, increased the transmission distance, and can allow voice and data with preach, can use a pair or two for twisted-pair cable, using OPTIS modulation technology, string words interference performance below 5 db. In the United States, HDSL2 solve traditional telecommunication companies to adopt high demand area copper wire, and a shortage of new communication companies to HDSL2 interest is it can save cost. In addition, HDSL2 can T released with itu-t G.S HDSL standards compliant. Because ETSI (Europe standardization organizations) delayed HDSL2 through, delayed it in the world of promotion, at present, the support of this standard products in the Chinese market use less.HDSL44th generation HDSL (high data bitrate digital subscriber line), is a higher version of the HDSL2, it through the use of two lines (and therefore, 4 wire) than HDSL or more than about 30% of the HDSL2 farther distance, however HDSL2 USES a pair of wire.HDSL the main application of:Telecom operators to provide customer 2M DDNDigital switches connectedHigh bandwidth video conferenceDistance teachingCellular phone base stations connectionSpecial network modelingThe enterprise internal network constructionBelow actual case about HDSL applications:Using a favorable long-distance 2M line networkApplication of two, LAN outspread