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[JoshShep]

Hi guys, just wondering if you can help me please, I'm about 500m from the cab, and was estimated 35meg. I'm getting around 25 as you can see below, I've unlocked the modem to see the stats and to me something doesn't look right. take a look please and tell me what you think. Like I said I'm 500m from the cab so I think I should be getting better results.

Thanks!

17a PROFILE!

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max:    Upstream rate = 6672 Kbps, Downstream rate = 33828 Kbps
Path:   0, Upstream rate = 2000 Kbps, Downstream rate = 26234 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083)
Medley Phase (Final) Band Plan
US: (0,95) (880,1195)
DS: (32,859) (1216,1959)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6672 kbps         33828 kbps
Actual Aggregate Tx Power:        5.8 dBm          10.3 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB):  4.4     46.7    62.4     N/A    20.4    58.4    0.1

Signal Attenuation(dB):  4.3     46.7     N/A     N/A    20.4    58.4     N/A

        SNR Margin(dB):  13.4    16.0     N/A     N/A    6.1     6.4      N/A

         TX Power(dBm):  0.4     4.2      N/A     N/A    8.8     5.3      N/A

[asbokid]

Hi guys, just wondering if you can help me please, I'm about 500m from the cab, and was estimated 35meg. I'm getting around 25 as you can see below, I've unlocked the modem to see the stats and to me something doesn't look right. take a look please and tell me what you think. Like I said I'm 500m from the cab so I think I should be getting better results.

Thanks!

17a PROFILE!

Code: [Select]

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max:    Upstream rate = 6672 Kbps, Downstream rate = 33828 Kbps
Path:   0, Upstream rate = 2000 Kbps, Downstream rate = 26234 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083)
Medley Phase (Final) Band Plan
US: (0,95) (880,1195)
DS: (32,859) (1216,1959)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6672 kbps         33828 kbps
Actual Aggregate Tx Power:        5.8 dBm          10.3 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB):  4.4     46.7    62.4     N/A    20.4    58.4    0.1
Signal Attenuation(dB):  4.3     46.7     N/A     N/A    20.4    58.4     N/A
        SNR Margin(dB):  13.4    16.0     N/A     N/A    6.1     6.4      N/A
         TX Power(dBm):  0.4     4.2      N/A     N/A    8.8     5.3      N/A


As you say, the throughput is rather low when you're only 500 metres from the cabinet.
Notice that the third DS band (D3) was discovered (DMTs #2792-#4083) but is unused.
Likely because of excessive attenuation at the higher frequencies  (12MHz-17MHz) used in that band

Paul (Baldy) has developed some sophisticated scripting tools to help pinpoint the cause of the problem..

cheers, a

[roseway]

[Originally posted by Bald_Eagle1]

As you say, the throughput is rather low when you're only 500 metres from the cabinet.
Notice that the third DS band (D3) was discovered (DMTs #2792-#4083) but is unused.
Likely because of excessive attenuation at the higher frequencies  (12MHz-17MHz) used in that band

Paul (Baldy) has developed some sophisticated scripting tools to help pinpoint the cause of the problem..

cheers, a

Just to add a comment:-

I see that the band plans discovered & actually in use are the "non-standard" ones that have only been seen rarely.

This is an example of my pbParams statistics & I am supposedly up to twice the distance from the cabinet.
Unfortunately the sync speed of 30292k is rather a one-off. Current sync speed is only 23670k:-

Code: [Select]

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 6231 Kbps, Downstream rate = 35676 Kbps
Path: 0, Upstream rate = 6209 Kbps, Downstream rate = 30292 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6231 kbps         35676 kbps
Actual Aggregate Tx Power:        6.2 dBm          12.3 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 52.2 63.8   N/A 21.4 62.5 0.1
Signal Attenuation(dB): 14.4 51.7   N/A   N/A 21.4 62.5   N/A
        SNR Margin(dB): 6.1 6.2   N/A   N/A 6.2 6.3   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.9 6.5   N/A

Power levels also appear quite low.
Is your cabinet a long way from the exchange & therefore power levels may have been turned down to avoid cross-talk onto nearby already quite weakened ADSL signals?


Paul.

[JoshShep]

Thanks for the help guys!