Adsl2+ basic principles, Vdsl2, Adsl2+ basic principles vdsl2 – EXFO VDSL2 User Manual
Page 13
 
Introducing the Copper, VDSL2, ADSL2+, and IP Triple-Play Test Set
Copper, VDSL2, ADSL2+, and IP Triple-Play Test Set
5
ADSL2+ Basic Principles
ADSL2+ Basic Principles
ADSL2+ based testing requires an ATU-C (ADSL Transceiver Unit - Central 
Office) that resides in a DSLAM (Digital Subscriber Line Access Multiplexer) 
in the Central Office/Local Exchange. At the customer premises, there is an 
ATU-R (ADSL Transceiver Unit - Remote) that interfaces with a user's PC. 
The Copper, VDSL2, ADSL2+, and IP Triple-Play Test Set allows you to 
emulate the ATU-R (customer’s ADSL modem). Once a connection is 
established with the ATU-C in the DSLAM at the service provider’s central 
office or remote DLC, the AXS-200/635 displays the connection rates for the 
upstream and downstream directions of the ADSL2+ link.
VDSL2
Very high speed digital subscriber lines (VDSL) is a standard that allows 
extremely high speed internet access over existing copper cables. The 
VDSL2 standard increases the spectrum allocation up to 30 MHz for even 
higher performance than its predecessor VDSL1, and allows speeds up to 
100 Mbps symmetrical (both up and downstream). VDSL2 also calls for 
support of applications such as multi-channel high definition TV (HDTV), 
video on demand, video-conferencing, and VoIP using the existing copper 
telephone line infrastructure. Along with that, it also calls for ATM, Ethernet, 
and IP compatibility, as well as multimode implementations to permit 
interoperability with existing ADSL equipment.
VDSL2 gives carriers the flexibility to start rapidly deploying VDSL2 
networks and offer new broadband services including triple-play services - 
HDTV, VoD, high-speed data, VoIP, high-speed Internet access, video 
conferencing, virtual private networks (VPNs), PBX Extension, and video 
surveillance - to compete with cable companies. VDSL2’s broader 
spectrum combined with features like Trellis coding and multi-pair 
bonding allows carriers to offer full triple-play services to a large portion of 
their customer base.