About the VDSL Switch-VS2512A
1-2VDSL Technology

VDSL (Very High Bit-Rate Digital Subscriber Line) is at the high-end of all the DSL

technologies, offering the best combination of fiber optics and copper to provi de

high-speed broadband Internet access. VDSL’s primary application is in providing a

broadband data service to multi-tenant residential or commercial buildin gs. In this

implementation, fiber optic cable carries data from an Internet Service Provider to

the building; then the installed telephone copper wires take the data and deliver it to

individual units within that building.

Figure 1-1. VDSL Application

VDSL provides high-speed Internet access over existing phone lines by making us e

of previously unused frequency bandwidth above the voice band. By placing VD SL

signals above the frequency of the voice signa l, a VDSL service can coexist on the

same line as other telephone services. VDSL can operate

symmetrically, providing

the same data rate in both directions, or

asymmetrically, providing

a higher data rate

in the downstream (receive) direction than in the upstream (transmit) directi on.

VDSL can deliver high-performance online applications, such as high-qualit y video

and other switched multimedia services. Accton's Ethernet-over-VDS L system

provides robust performance, with a symmetric data rate up to 15 Mbps, and a range

up to 1525 m (5000 ft). Accton’s system is based on advanced VDSL QAM

(Quadrature Amplitude Modulation) technology with adaptive channel equalization

that overcomes bridge taps and other line distortions. Reed-Solo mon Forward Error

Correction and interleaving protects against errors due to impulse noise and enables

recovery from signal interruptions. Frequency Division Duplexing (FD D) separates

downstream and upstream channels and allows VDSL signals to coexist with regular

telephone services. A power back-off mechanism is also implemented to reduc e

noise from crosstalk in line bundles.

ISP

(Internet)

CentralOffice

(PSTN)

PunchDown
Blocks/
PatchPanels
PBX
Telephone/Fax
Telephone
ES2002-TS
VDSLCPE
VDSL
Splitter-VM2524
VDSL
Switch-VS2512A
TelephoneLine from Central Office
FiberOptic Link to ISP
LocalServers
(LocallyHosted Services,
VideoServers, Billing)
ExistingPhone
Linesto Clients
Multi-dwelling/Multi-tenantBuilding
Floor2
Floor1
Rooms/Clients
Rooms/Clients
VDSLLines
Line
Line
VDSLSplitter-VM2524
VDSLSplitter-VM2524
VM2524
VM2524
PhoneLines
VM2512A-4FX-MTRJ-S
VM2512A-4FX-MTRJ-S
100BASE-FXSinglemodeModule
100BASE-FXSinglemodeModule
ExpansionModuleVDSLSwitch-VS2512A
VDSLSwitch-VS2512A
Reset
Reset
Power
Power
Stacking
Stacking
Diag
Diag
Master
Master
On
On
Off
Off
Up
Up
Down
Down
Stacking
Stacking
VS2512A
Console
Console
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10
10
11
11
12
12
VDSL
VDSL
1
1
Activity
Activity
Link
Link
Activity
Activity
Link/Speed
Link/Speed
1
1
2
2
3
3
4
4
Ethernet
Ethernet
100-240V~50-60Hz1A
ES2002-TS
VDSLCPE