- Status
The_Devil_Himself
die blizzard die! D3?
hehe you all are lucky dawgs 
MTNL upgraded my speeds to 2046\256kbps(down\up) a few days ago,the connection wasn't stable,I complained a lot,they,instead of changing my line and doing other things,reduced my down speeds to 288kbps!!Thsi sux.Now I am surviving on 288kbps and you all are talking about 8mbps.I feel like killing MTNL.
MTNL upgraded my speeds to 2046\256kbps(down\up) a few days ago,the connection wasn't stable,I complained a lot,they,instead of changing my line and doing other things,reduced my down speeds to 288kbps!!Thsi sux.Now I am surviving on 288kbps and you all are talking about 8mbps.I feel like killing MTNL.
Cyrus_the_virus
Unmountable Boot Volume
Can you refer back to my last post? It says that the modulation type used is DMT which includes G.Dmt. Whatever modulation your router uses should be compatible with the DSLAM modulation and BSNL's DSLAMs use DMT Modulation.Harvik780 said:
Guys, please don't use this link. It's meant to estimate the speed for UK customers who are running the DSL MAX package which is rolled out by BT(British Telecom). Although you will get resuls if you put in values because it's just an estimate calculation tool, still, it's not meant for reference for those who are on BT's DSL MAX.cool_techie_tvm said:
Once again, please don't be confused. ADSL 2+ has been the technology behind BSNL's broadband ever since it launched. It's not something new. The 8Mbps trials that are being carried out are on the same ADSL2+ technology. It's just that some modems will say ADSL while others will say ADSL2+.
Last edited:
Ponmayilal
Attitude matters
I think that BSNL is shifting to Rate adaptive ADSL connections.
I opted to surrender the BSNL rented ADSL modem Huawei MT 800 since I have my own Netgear DG834G modem/router/accesspoint.By mistake (?????) the Commercial officer ordered disconnection of my Broadband connection. I had to live with it from 21 to 27th Nov, when finally the Broadband connection was restored after I made a hue and cry and sounded the top officials of BSNL on their negligent act. But ever since the connection was restored I have noted that my Netgear modem gives out the following statistics.
With my old connection the corresponding readings were more or less as follows
Connection speeds 2048Kbps/256 Kbps
Line attenuation 48db/28db
Noise margin 22db /22db
I was more concerned about the downstream noise margin which now varies from 0db to 10 db.(most of the time 6 db) At such low noise margin I expected that the connection would drop frequently but surprisingly the connection has never dropped during the last 36 hours since the new connection.The only thing I had observed is that the speeds are never consistent. Sometimes it drops to as low as 200Kbps but most of the time it is around 800Kbps.
Alarmed I made a quick websearch on 27th night itself and came to know about the MaxDSL. Here is the link *www.kitz.co.uk/adsl/maxdsl2.htm
It is now quite obvious that BSNL is now changing over to the Rate adaptive MaxDSL which is just a variation of the ADSL2+. Low SNR margin is to be expected for this type of connection.I also understand that it takes about ten days for the ADSL system to stabilise and fix up the maximum possible download speed for the particular line.
Today the JTO visited my residence to collect the BSNL modem and I queried him on the very low SNR margin of the line. He had no clue whatsoever!!!!!!!
I opted to surrender the BSNL rented ADSL modem Huawei MT 800 since I have my own Netgear DG834G modem/router/accesspoint.By mistake (?????) the Commercial officer ordered disconnection of my Broadband connection. I had to live with it from 21 to 27th Nov, when finally the Broadband connection was restored after I made a hue and cry and sounded the top officials of BSNL on their negligent act. But ever since the connection was restored I have noted that my Netgear modem gives out the following statistics.
ADSL Link
Downstream
Upstream
Connection Speed
4902 kbps
509 kbps
Line Attenuation
51 db
13 db
Noise Margin
2 db
21 db
With my old connection the corresponding readings were more or less as follows
Connection speeds 2048Kbps/256 Kbps
Line attenuation 48db/28db
Noise margin 22db /22db
I was more concerned about the downstream noise margin which now varies from 0db to 10 db.(most of the time 6 db) At such low noise margin I expected that the connection would drop frequently but surprisingly the connection has never dropped during the last 36 hours since the new connection.The only thing I had observed is that the speeds are never consistent. Sometimes it drops to as low as 200Kbps but most of the time it is around 800Kbps.
Alarmed I made a quick websearch on 27th night itself and came to know about the MaxDSL. Here is the link *www.kitz.co.uk/adsl/maxdsl2.htm
It is now quite obvious that BSNL is now changing over to the Rate adaptive MaxDSL which is just a variation of the ADSL2+. Low SNR margin is to be expected for this type of connection.I also understand that it takes about ten days for the ADSL system to stabilise and fix up the maximum possible download speed for the particular line.
Today the JTO visited my residence to collect the BSNL modem and I queried him on the very low SNR margin of the line. He had no clue whatsoever!!!!!!!
The_Devil_Himself
die blizzard die! D3?
^^err...a very noobish question to you all--does the line itself determines the max. down speeds that it can sustain and then fix up on that?I mean my down speeds is now 288kbps(connection is very stable now) after about a week of having a very unstable 2mbps speeds.What can I do now except for calling dumba&&es over at MTNL callcanters(I don't trust MTNL at all,they're all incompetent)?
edit:will purchasing the abovesaid router help(over MTNL's default router,some crappy U2-304R2)?
edit:will purchasing the abovesaid router help(over MTNL's default router,some crappy U2-304R2)?
Cyrus_the_virus
Unmountable Boot Volume
Ponmayilal said:
BSNL is testing the 8Mbps service which is rate Adaptive but it's not going to be know by the name MaxDSL. That is the name of the product released by BT like the name Dataone that BSNL uses for it's broadband.
But when the connection means rate adaptive it doesn't mean that the connection speed will keep varying always. It's going to be adaptive only during the testing phase after which your speed will be fixed.
I guess it's better I write an article on how these things work to avoid confusion
The_Devil_Himself said:
Well, there are a million reasons why the connection can be unstable but yes, the line conditions do affect the maximum possible speed. Things like SNR and line attenuation play ver important roles in maximum possible speed.
Last edited:
Ponmayilal
Attitude matters
^^Basically the maximum speed that you can get on your line in any ADSL connection depends upon the line( Its length from the exchange to your residence, its thickness responsible for signal attenuation and the noise present on it).Most service providers will deny an ADSL connection to you if they determine that your line cannot sustain the minimum assured speed or a reasonably good speed.While the distance and thickness of the line do not vary, the noise is a variable.In maxdsl , if you read the link provided , you may understand that the DSLAM at the exchange and your modem take into account the variations of noise level and fix the optimum speed for your particular line.Atleast that is what I understand
Cyrus_the_virus
Unmountable Boot Volume
Thanks for your concern but I'm already working with MaxDSL for several BT clients like Tiscali, Pipex, Thus and Demon. That is why I was asking if I needed to write an article on this since it seems like all the similar related technologies are coming to India.Ponmayilal said:^^Basically the maximum speed that you can get on your line in any ADSL connection depends upon the line( Its length from the exchange to your residence, its thickness responsible for signal attenuation and the noise present on it).Most service providers will deny an ADSL connection to you if they determine that your line cannot sustain the minimum assured speed or a reasonably good speed.While the distance and thickness of the line do not vary, the noise is a variable.In maxdsl , if you read the link provided , you may understand that the DSLAM at the exchange and your modem take into account the variations of noise level and fix the optimum speed for your particular line.Atleast that is what I understand
Last edited:
Ponmayilal
Attitude matters
@cyrus, my last post was more specifically to the devil himself. Glad to know that you work for Maxdsl.I had only given my observation that the speed right now keeps varying.But I have understood the process and have clearly mentioned that after the training period of ten days the speed may be fixed.At this point of time there is no specific name for the BSNL's rate adaptive technology used and so no harm if we call it by the only reference known at this point of time - MaxDSL . Going through this thread, you may appreciate that none had a clue about this rate adaptive ADSL technology and I had given all a reference article on MaxDSL and through that the working of the rate adaptive ADSL, specifically clearing the confusion regarding the low downstream noise margin. I myself was confused three days ago There is no need for any new articles if articles on the subject already exist. So you may give reference to such articles.BTW there is no more Dataone. Effective 01 Nov 2007 it is just BSNL Broadband
. Going through this thread, you may appreciate that none had a clue about this rate adaptive ADSL technology and I had given all a reference article on MaxDSL and through that the working of the rate adaptive ADSL, specifically clearing the confusion regarding the low downstream noise margin. I myself was confused three days ago There is no need for any new articles if articles on the subject already exist. So you may give reference to such articles.BTW there is no more Dataone. Effective 01 Nov 2007 it is just BSNL Broadband
Cyrus_the_virus
Unmountable Boot Volume
Ponmayilal said:@cyrus, my last post was more specifically to the devil himself. Glad to know that you work for Maxdsl.I had only given my observation that the speed right now keeps varying.But I have understood the process and have clearly
.............
..........................
y new articles if articles on the subject already exist. So you may give reference to such articles.BTW there is no more Dataone. Effective 01 Nov 2007 it is just BSNL Broadband
But, your post was actually pointing to mine, so that's the reason I replied
Anyways, as you might notice, I've been mentioning in my posts not to compare this with MaxDSL as the 8Mbps implementation might be completely different in India. So, lets keep these comparisons clear of doubts till BSNL comes out with some technical details.
Ponmayilal
Attitude matters
ya, by the time I posted a reply to devil you had come inbetween the devil and the deep sea and I did not see
Last edited:
praka123
left this forum longback
G.DMT mode and d/l is 2048kbps u/l is 512kbps
SNR for d/l is 25 and u/l is 22kbps
upstream attenuation 21.5 dB downstream 40.0 dB <==too much!
No BW increase.i am getting a constant 1.75mbps speed in daytime and in night it goes upto 1.84 Mbps.have to satisfy with this
No 8mbps test or nothing here.
SNR for d/l is 25 and u/l is 22kbps
upstream attenuation 21.5 dB downstream 40.0 dB <==too much!
No BW increase.i am getting a constant 1.75mbps speed in daytime and in night it goes upto 1.84 Mbps.have to satisfy with this
No 8mbps test or nothing here.
Ponmayilal
Attitude matters
Yep @praka123,I presume that if attenuation is less you may perhaps get a more consistent speed rather than increased speed in the fixed rate system since there is no feedback of this info to the ADSL system. Before my BB was disconnected by BSNL (on 21 Nov), I was getting more or less the same readings as yours and the speed was also consistent.When they reconnected on 27 Nov, I got the different readings and what was particularly alarming was the low SNR margin of 6db and its variation.That drove me into the research mode that gave the clue of the rate adaptive ADSL technology where such low SNR margins are to be expected.(The SNR margin is the difference between the actual signal level in db and the noise level in db in the line and the system as I understand tries to keep this margin at the default 6db level by a feedback of this info to the ADSL system.) As I said even the BSNL staff dealing with external installation are totally unaware of this, much less the customers.May be slowly all lines will get connected to this rate adaptive technology.(As Cyrus the Virus rightly pointed out MaxDSL is the brand name of the BT services in UK, and he had opined that the implementation of the rate adaptive technology by BSNL might be different.I presume that the fundamental principles will remain the same) I shall wait for the supposed ten day training period to be over, check and report whether the speed gets fixed & consistent. Right now I am on day 5.
Last edited:
^^He also made my confusion clarified but What i have seen is that BSNL employees are not updating every users download speed.Maybe they are too lazy to do so or maybe i should wait for cyrus_the_virus to explain why not I saw 2048 Ds on my friend's ADSL line and 8064 Ds on my ADSL line with the same modem.
Cyrus_the_virus
Unmountable Boot Volume
As you would agree, the modem doesn't make a difference here. So, the only thing that differs is the line. Now, because this is India do you think BSNL is going to run 2 technologies on the same DSLAM or same exchanges with different DSLAM parallely at the same time? The answer is no. However, to clarify this. ADSL2+ technology doesn't mean that it cannot be 2Mbps. ADSL2+ technology varies upto 24Mbps theoretically. So, don't be confused that your friend is on ADSL and your line on ADSL2+. It's the same for both of you which is ADSL2+.Harvik780 said:
However, the reason that we all are getting 2Mbps is because it's capped at 2Mbps which means all our lines are set to a maximum of 2Mbps although they can handle more. That is why, they are NOT going to run around changing everybody's line to upgrade to 8Mbps. It's going to be the same line. The change that is going to happen is that the DSLAM are going to "Let Loose" the ADSL lines which means they are going to run at maximum possible stable speed on your line which means, it's going to push your telephone line to it's limits. Now this is where people who have not so good a line are going to see maybe 2-3Mbps while those with good lines will see 7-8Mbps. The process of 'letting loose' is beyond the scope of this post to explain in detail.
However, I have to say that the words 'Rate Adaptive' is a bit more complicated and not just related to the SNR. There is lot more happening in the backend and I must warn you that if lines are switched to rate adaptive, some line which are already stable on 2Mbps might see speeds as low as 256-512Kbps..
praka123
left this forum longback
i have my huawei mt 880 modem showing ADSL earlier(a year before) and i updated to custom firmware for MT882.it made much difference,and from that time it showed ADSL State :Show Time earlier it was someother thing :forgot:
Now in the modem info page it is shown:
Output Power:11.7 dB
^^^what is it?is this value good.already SNR~25 downstream
and which one shud i enable out of below options:
EC/FDM Mode: I have FDM mode enabled after i read about FDM(Freq Div Multiplexing) Does it have any impact on speed?by default it was set as "EC"( [SIZE=-1]echo cancellation[/SIZE])
also BitSwap=enabled
I donno much about all these.help pls.
please clarify also my modem is 1.5+ yrs old given by bsnl.does using a new modem gives better speed.my modem is already hacked to give equivalant performance to that of MT882
Now in the modem info page it is shown:
Output Power:11.7 dB
^^^what is it?is this value good.already SNR~25 downstream
and which one shud i enable out of below options:
EC/FDM Mode: I have FDM mode enabled after i read about FDM(Freq Div Multiplexing) Does it have any impact on speed?by default it was set as "EC"( [SIZE=-1]echo cancellation[/SIZE])
also BitSwap=enabled
I donno much about all these.help pls.please clarify
also my modem is 1.5+ yrs old given by bsnl.does using a new modem gives better speed.my modem is already hacked to give equivalant performance to that of MT882 - Status