Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Author Topic: Just interested: what does this mean?  (Read 2484 times)

renluop

  • Kitizen
  • ****
  • Posts: 3326
Just interested: what does this mean?
« on: July 16, 2013, 11:52:14 AM »

Telnet on my 582N has this line "INP [DMT symbols] Downstream 1.3 Upstream 2.0. What do those values do?
Logged

roseway

  • Administrator
  • Senior Kitizen
  • *
  • Posts: 43472
  • Penguins CAN fly
    • DSLstats
Re: Just interested: what does this mean?
« Reply #1 on: July 16, 2013, 12:41:41 PM »

INP is Impulsive Noise Protection. It's a Broadcom feature to improve the resilience of a connection under impulse noise conditions.

DSLstats should copy these figures to the main Stats page, but at present this doesn't happen with Technicolor routers.
Logged
  Eric

renluop

  • Kitizen
  • ****
  • Posts: 3326
Re: Just interested: what does this mean?
« Reply #2 on: July 16, 2013, 02:49:23 PM »

Hi! I'd sussed what the INP meant. ;D, so was more interested in the values and their interpretation.
Logged

roseway

  • Administrator
  • Senior Kitizen
  • *
  • Posts: 43472
  • Penguins CAN fly
    • DSLstats
Re: Just interested: what does this mean?
« Reply #3 on: July 16, 2013, 03:41:06 PM »

I was wrong to say that it's a Broadcom feature, but Broadcom have improved on it.

I'm not really competent to go into detail, but broadly speaking it's a compromise between speed and resilience. Without the Broadcom extensions at the exchange end, higher values result in lower connection speeds, and values over 2 can render the connection incapable of syncing. Values less that 1 are more normal.
Logged
  Eric

ryant704

  • Reg Member
  • ***
  • Posts: 318
Re: Just interested: what does this mean?
« Reply #4 on: July 16, 2013, 06:01:48 PM »

INP is a symbol, if INP is set it's normally set at 3. You have 3 (If set at 3 INP) symbols to protect against high amount of errors this is due to noise on the line. The more symbols the more errors/noise that there is on your line and to deal with this it has to allocate a high INP value. On a normal Interleaved line you're looking at 3 or 3.25 INP value.

Worth noting this also relation to other values to your line such as block sizes for your line, etc.
« Last Edit: July 16, 2013, 06:04:08 PM by ryant704 »
Logged

renluop

  • Kitizen
  • ****
  • Posts: 3326
Re: Just interested: what does this mean?
« Reply #5 on: July 16, 2013, 07:05:38 PM »

INP is a symbol, if INP is set it's normally set at 3. You have 3 (If set at 3 INP) symbols to protect against high amount of errors this is due to noise on the line. The more symbols the more errors/noise that there is on your line and to deal with this it has to allocate a high INP value. On a normal Interleaved line you're looking at 3 or 3.25 INP value.

Worth noting this also relation to other values to your line such as block sizes for your line, etc.
So my interleaved line does not conform to the normal values, you quote. hmmm.

I can see nothing about blocks in telnet, but this is the current info in the section dealing with INP

Code: [Select]
    Number of bearers:          1
    Bearer 0                    DS          US       
      INP [DMT symbols]:    1.22         2.00           
      Delay [ms]:            7.99         8.00           
      Depth []:            64             0.00
      R:                  10        0       
Logged

ryant704

  • Reg Member
  • ***
  • Posts: 318
Re: Just interested: what does this mean?
« Reply #6 on: July 16, 2013, 09:12:59 PM »

The INP can be any value but normally the value is 3 from experince.

They aren't actually called blocks, they're your R Value etc but I cannot remember which off the top of my head.

R:      12      16

They aren't directly related, you should be looking at INP + delay. The block sizes aka I, R and N values are also part of INP (sort of), I'm sure some will disagree.
« Last Edit: July 16, 2013, 09:21:24 PM by ryant704 »
Logged