BRX-VDSL2 User Guide
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180-0153-001-R02
Figure 27: Grounding and Bonding Strand-Mount Units
8.2
Impulse Noise Protection
While the BRX-VDSL2 is very effective at mitigating the impact of longer loops and the resulting
higher signal attenuation, there are other factors that will negatively impact the performance of a
VDSL2 loop. The Impulse Noise Protection (INP) capabilities of the DSLAM help to mitigate the
impact of noisy lines. Proper grounding and bonding of the equipment in the copper Outside Plant
(OSP) can also help improve the quality and performance stability of copper loops. A symptom of a
strong power influence is when AC voltage appears on Tip-Ring or Ring-Ground or Tip-Ground.
Another potential problem is that copper pairs may not have been properly balanced. An unbalanced
pair is more susceptible to Power induction and noise.
Based on the extensive field testing of the BRX-VDSL2 performed with Operators in very different
regions, markets and countries, it has become obvious that the Impulse Noise Protection (INP)
characteristic that is included in most DSLAMs (at least those that adhere to the G.993.2 VDSL2
standard) can significantly help to stabilize the bandwidth delivered to subscribers, resulting in an
overall better Quality of User Experience.
For more information on this subject, please refer to Annex A, an excerpt from the Broadband Forum
TR-
176 document entitled “ADSL2Plus Configuration Guidelines for IPTV”.
