DSLAMS moving closer to you

!!DV!! said:
Telkom has been installing DSLAM / UMC and other equipment is street cabinet for quite sometime. If you look at some of the gated estates.
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This is true where I am. Not an estate at all - ordinary residential suburb. Fibre comes up the road from town where it terminates in a nondescript ( no stickers! ) box on the side of the road. It has been like this for at least a few years. Inside the grey box is a beautiful looking device called a UMC-1000-something ( can't remember ). All brushed aluminium and pretty LEDs. It is like a card cage, and the ADSL cards take 5 lines each. According to the tech who let me look it is hugely expandable. There is other stuff in the grey box - for plain phone lines, lightning protection lugs, UPS and batteries. The tech also claimed that the ADSL cards for the device were specifically designed for Telkom and local conditions ( I have no idea if that is true ).
 
well those figures would be amazing for adsl, but i didnt know they applied to wireless? noise margin ya, but isnt line attenuation only associated with wire?
 
o sori, i thought u had iburst.. well, if you were to upgrade to 4mb you would get excellent speeds.. the lower your attenuation and higher your snr, the better..
 
@Rockford: A very interesting observation. I think that you might be referring to the Advanced Fibre Communications Universal Modular Carrier 1000 series. AFC is now part of Tellabs.

This is from Tellabs website -
Our customers include wireline, wireless and cable TV companies, as well as government agencies. Verizon, BellSouth, NTT Communications of Japan, Telstra of Australia, Telkom South Africa and Telecom Italia are among our customers.
Click to expand...

Some of the UMC-1000 series products
http://www.tellabs.com/products/1000/tlab1900-48_rsc.pdf
http://www.tellabs.com/products/1000/tellabs1000.shtml

Some background about Advanced Fibre Communications
http://findarticles.com/p/articles/mi_gx5202/is_1992/ai_n19122085/pg_1
 
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ocean-addict said:
arent the blue and green telkom boxes the ones with dslams? there are only a few of them here and there..

if these dslams become full, then theyll most likely route all other customers to the main exchange, so there may be a dslam just down the road with no available ports and so instead you have to put up with 63db attenuation..
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nah, the ones i've seen close to my house is just white with a smallish telkom logo. will take some pics.

* EDIT: the blue and green ones are copper junction (or distribution) boxes. *
 
@Luke7777: Those are very good linestats. You should be able to get close to the maximum ADSL2+ speed of 24Mbps (when available) if you are so close to the DSLAM.

Are you connected to a normal exchange or via a mini DSLAM/UMC? If you have a Netgear DG834G (Mega 100WR?) you should be able to identify the manufacturer of your DSLAM from the command line interface i.e. telnet to your router's IP address, type in your username (root for Mega 100WR?) and password and then issue the command cat /proc/avalanche/avsar_modem_stats - you should get a screen of information which includes an ATUC vendor code as well as some information about the hybrid i.e. if the vendor code is TSTC then you are probably connected to a Marconi/Ericsson? ADSL2+ DSLAM at the exchange. If it is IFTN then you may be connected to a Huawei mini DSLAM etc.

ATUC Vendor Codes:
414C4342 = ALCB Alcatel (ST Micro)
414E4456 = ANDV Analog Devices
4244434D = BDCM Broadcom
4753504E = GSPN Globespan
4946544E = IFTN Infineon (Huawei)
53544D49 = ST Micro
54535443 = TSTC Texas Instruments
544D4D42 = TMMB Thomson Multimedia Broadband
 
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Something that I have noted is that the telnet command doesnt work in Vista. Is there another command that performs the same thing or isnt it present at all ?
 
Luke7777 said:
the command "cat /proc/avalanche/avsar_modem_stats" doesn't work on my 834G. Used "http://192.168.0.1/setup.cgi?todo=debug" to be able to telnet into the router.
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Forgot to add that the "avalanche" directory doesn't exist under /proc on mine

/oops...seems I have a 834GT and not an 834G
 
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@Luke7777: That cat command will only work on some TI AR7 (Texas Instruments) based routers such as the Netgear DG834G v.1,2,3 (not v.4!). The DG834GT is based on the Broadcom BCM6348 chipset which does not appear to offer any similar feature to query the ATUC vendor code. In general though, the Broadcom based ADSL routers are far superior to the TI based ones in terms of their ability to handle noisy lines etc.
 
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So I was wondering whether I should upgrade from 512kbps to 4mbps so I checked my line attenuation stats, what a surprise. I must be really far away from the DSLAM.

ADSL Link Downstream Upstream
Connection Speed 512 kbps 256 kbps
Line Attenuation 61 db 15.5 db
Noise Margin 5 db 12 db

I connected to my router via telnet and executed that command to get the stats. My ATUC Vendor Code is 54535443. It also says that my Downstream Max Attainable Bit Rate is 2112kbps so I wonder whether it is worth getting 4mbps. I guess a 4x speed increase is okay if that figure is accurate.
 
@noosh: The difference between your downstream and upstream attenuations seems a bit large i.e. 61dB down and 15.5dB up. Would it be possible to find out from Telkom exactly where your exchange is situated? If it's roughly 4km away then 512k might be the best that you can hope for - you may even have to downgrade to 384k if you have stability problems at 512k since your downstream noise margin is very low at 5dB. If the exchange is a lot less than 4km away then there might be some kind of problem that is increasing the downstream figure. What hybid number is your router reporting? You should be able to find this figure in the data which includes the ATUC Vendor Code. See this link for more information about the hybrid number for the TI AR5/7 chipset.

http://www.dslreports.com/faq/sbc/3.1_Speedstream_5100b___4100

It appears that you are connecting to a Marconi (TI based) ADSL2+ DSLAM with a TI AR7 based router which should be a good match.

It might also be useful to download routerstats to monitor both your downstream noise and attenuation values to see if the variations are excessive. You could also try to get a bits per tone plot using a program called OrbMT. If necessary choose the Sphairon AR860[V1/2], Netgear DG834B etc. (TI AR7 Chipsatz [Avalanche SAR Software]) option.

Routerstats
http://www.vwlowen.co.uk/internet/files.htm
OrbMT
http://blog.orbmu2k.de/tools/orbmt-modem-tool-sidebar-gadget/
 
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noosh said:
So I was wondering whether I should upgrade from 512kbps to 4mbps so I checked my line attenuation stats, what a surprise. I must be really far away from the DSLAM.

ADSL Link Downstream Upstream
Connection Speed 512 kbps 256 kbps
Line Attenuation 61 db 15.5 db
Noise Margin 5 db 12 db

I connected to my router via telnet and executed that command to get the stats. My ATUC Vendor Code is 54535443. It also says that my Downstream Max Attainable Bit Rate is 2112kbps so I wonder whether it is worth getting 4mbps. I guess a 4x speed increase is okay if that figure is accurate.
Click to expand...

in all honesty - nope - with a noise margin that low - you are not even going to make a stable 1024 profile.
 
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