5.8 MG vs. 2.4 MG?

Obelix said:
*i just heard of a case where this did happend, but it was overturned at a lter stage again, so..... draw your own conclusions. Are you prepared to take on Telkom & icasa on ISM pollution? *
Click to expand...
Obelix - do you have more info on this? post/pm
 
Megawan PMB.

Local judge sees a complaint from Telkom, thinks "oh crap, its telkom, they must be right". signs the order.

All Megawan PMB equipment gets confiscated because there were causing interference with Telkoms 2.4Ghz equipment.

Completely against the rules of "no complaints will be entertained"
A long court battle later, the ruling was overturned, and I spent a few days in PMB rebuilding the network.

Ancient history :) Must have been about 6 years ago..
 
daffy said:
Megawan PMB.

Local judge sees a complaint from Telkom, thinks "oh crap, its telkom, they must be right". signs the order.

All Megawan PMB equipment gets confiscated because there were causing interference with Telkoms 2.4Ghz equipment.

Completely against the rules of "no complaints will be entertained"
A long court battle later, the ruling was overturned, and I spent a few days in PMB rebuilding the network.

Ancient history :) Must have been about 6 years ago..
Click to expand...
thanks - know the ultimately sad megawan story - was wondering if there was something more recent...
 
Only a Copper pair can only be used by 1 DSL link. Look at the way the DSL techs work. They use all the high frequencies on the line. How can you have more than 1 modem using the same frequencies? You cant. Catch a clue.
Click to expand...

http://www.auditmypc.com/acronym/DSLAM.asp
"... which takes a number of ADSL subscriber lines and concentrates these to a single ATM line."
http://www.c-com.com.tw/c-com-products-ipam-4800.htm
Download the pdf document on page 2 it states that eight modems can be connected to a single port.
http://www.c-com.com.tw/Data Sheet/DM-IPAM-4800-v.1.2.pdf

An Adsl modem uses both Ethernet and ATM. Ethernet connects to the end-user's PC, but ATM is used to connect the Adsl modem to the Dslam. There is an inherent distance limit to the ethernet protocol, thus it can only be used upto a 100m on copper. Telkom has stated that it's Wimax 3.5ghz will complement it's Dslam operations. Telkom leverages all technologies(Dslam,2.4ghz backhaul, Wimax) available to it and so should we. Many Dslams have what is known as a POTS splitter. It enables one to speak on the phone and browse the web via the Adsl modem on the same copperline at the same time.

It is difficult to get information on Dslam deployment. The people who have smuggled the stuff into the country and secretly sold it to Holiday Inn went underground.

Even with just eight modems on a R1000 Adsl-Dslam multiplexing data at distances of over 5km down a 0.5mm copper wire, it is still the prefered sollution for close proximity communication, like hotels and residential areas - just ask Telkom! Wireless is ideal to bridge islands of Dslam clusters over long distances.

http://www.huawei.com/products/access/products/view.do?id=107&pageId=107_0
http://electronics.howstuffworks.com/vdsl.htm
http://www.auditmypc.com/acronym/DSLAM.asp
http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/adsl.htm
http://www.iec.org/tutorials/vdsl/
 
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captainwifi said:
I read somewhere the max nr. of modems on a single Dslam port is eight. I lost the reference though.
http://www.auditmypc.com/acronym/DSLAM.asp
"... which takes a number of ADSL subscriber lines and concentrates these to a single ATM line."
An Adsl modem uses both Ethernet and ATM. Ethernet connects to the end-user's PC, but ATM is used to connect the Adsl modem to the Dslam.
There is an inherent distance limit to the ethernet protocol, thus it can only be used upto a 100m on copper. Both xDSL and Dslam uses the ATM protocol. They differ in that xDSL is a point-to-point bridge where Dslam is a switch.

Telkom has stated that it's Wimax 3.5ghz will complement it's Dslam operations. Telkom leverages all technologies(Dslam,2.4ghz backhaul, Wimax) available to it and so should we. Many Dslams have what is known as a POTS splitter. It enables one to speak on the phone and browse the web via the Adsl modem on the same copperline at the same time.

It is difficult to get information on Dslam deployment. The people who have smuggled the stuff into the country and secretly sold it to Holiday Inn went underground.

Even with just 8-ports using a R1000 Adsl-Dslam multiplexing data at distances of over 5km down a 0.5mm copper wire, it is still the prefered sollution for close proximity communication, like hotels and residential areas - just ask Telkom! Wireless is ideal to bridge islands of Dslam clusters over long distances.

http://www.huawei.com/products/access/products/view.do?id=107&pageId=107_0
http://electronics.howstuffworks.com/vdsl.htm
http://www.auditmypc.com/acronym/DSLAM.asp
http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/adsl.htm
http://www.iec.org/tutorials/vdsl/
Click to expand...

(quoted for truth)

Perhaps you need a basic course on the 7 basic OSI layers of networks.
DSL technology is the link layer (second layer), it doesn't matter what runs on top of it.
It can be ATM or Ethernet, it has nothing to do with the fact that its DSL.

The only reason Telkom are doing ATM over their ADSL, is because their network is ATM based.

A DSLAM is a DSL Access Multiplexer. Get it? ITS DSL.
A DSLAM is a nice way of putting a whole bunch of DSL modems into 1 box.

So if its a 24-port DSLAM, that means it has 24 DSL ports. Like a switch.

Why dont you try to absorb some of the information you google instead of just generating garbage with it?
 
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captainwifi said:
Download the pdf document on page 2 it states that eight modems can be connected to a single port.
http://www.c-com.com.tw/Data Sheet/DM-IPAM-4800-v.1.2.pdf
Click to expand...

The exact line from the PDF says

- 8 VCs per xDSL port

That doesn't mean 8 end users, that means up to 8 "virtual networks".
Go check your ADSL router configuration, where your VCI is set to 35.
On the Telkom network, they use VC number 35 for ADSL.

They could start deploying a seperate virtual network on VC 36 for example. Using DSL as the last mile link, but not for internet access.
 
captainwifi said:
Only a Copper pair can only be used by 1 DSL link. Look at the way the DSL techs work. They use all the high frequencies on the line. How can you have more than 1 modem using the same frequencies? You cant. Catch a clue.
Click to expand...

http://www.auditmypc.com/acronym/DSLAM.asp
"... which takes a number of ADSL subscriber lines and concentrates these to a single ATM line."
http://www.c-com.com.tw/c-com-products-ipam-4800.htm
Download the pdf document on page 2 it states that eight modems can be connected to a single port.
http://www.c-com.com.tw/Data Sheet/DM-IPAM-4800-v.1.2.pdf

An Adsl modem uses both Ethernet and ATM. Ethernet connects to the end-user's PC, but ATM is used to connect the Adsl modem to the Dslam. There is an inherent distance limit to the ethernet protocol, thus it can only be used upto a 100m on copper. Telkom has stated that it's Wimax 3.5ghz will complement it's Dslam operations. Telkom leverages all technologies(Dslam,2.4ghz backhaul, Wimax) available to it and so should we. Many Dslams have what is known as a POTS splitter. It enables one to speak on the phone and browse the web via the Adsl modem on the same copperline at the same time.

It is difficult to get information on Dslam deployment. The people who have smuggled the stuff into the country and secretly sold it to Holiday Inn went underground.

Even with just eight modems on a R1000 Adsl-Dslam multiplexing data at distances of over 5km down a 0.5mm copper wire, it is still the prefered sollution for close proximity communication, like hotels and residential areas - just ask Telkom! Wireless is ideal to bridge islands of Dslam clusters over long distances.

http://www.huawei.com/products/access/products/view.do?id=107&pageId=107_0
http://electronics.howstuffworks.com/vdsl.htm
http://www.auditmypc.com/acronym/DSLAM.asp
http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/adsl.htm
http://www.iec.org/tutorials/vdsl/
Click to expand...

(quoted, again, for truth)
A few edits throughout the whole thing, so I quoted the whole thing this time.
Notice how he included a quote from me in this one...
 
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daffy said:
(quoted, again, for truth)
Tell you what.. you, dig up a whole bunch of holes, put up telephone poles, and string some cable along them. I'll stand on the roof and mount an antenna. We'll see who gets it done first.
Wimax is not the killer solution to all our problems. Its all hype. Anyone who believes that 1 standard is going to be the silver bullet to cure all telecoms ailments, needs a bullet to the head.
Click to expand...

mmh ..bullet to the head. Perhaps you should calm down ;)
Your technical knowledge is impressive. So why are you deliberately confusing the issues here? I obviously didn't know one could only connect one modem to a port. In what way does this invalidate the thrust of my argument that one
should activly use Adsl Dslams where it makes sense and Linksys WRT54g gear where it is more appropriate?

And Obelix nobody is openly selling Dslams especially not Pinnacle, since they are a business who has to build
a brand name and thut can't sell stuff without Icasa's permission. It places the IT world in a very difficult position.

Lets forget about my telephone poles here for a few seconds, it really seems to get people worked up.
Just look at the incredilbe specs on http://www.c-com.com.tw/Data Sheet/DM-IPAM-4800-v.1.2.pdf
So basically (and if I am wrong try not to rub it in :)) where pinnacle is selling a 48-port switch that can only
do a 100m over bulky cables C-com is selling a 48-port switch/router combination wth Traffic prioritization (802.1p), bandwidth management by MAC and IP address etc that can do 5km.
 
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captainwifi said:
And Obelix nobody is openly selling Dslams especially not Pinnacle, since they are a business who has to build
a brand name and thut can't sell stuff without Icasa's permission. It places the IT world in a very difficult position.
Click to expand...
I guess having an item on you your price list doesnt mean your selling it ?!
 
Azrael said:
Dlink 48 port Stackable IP DSLAM with built-in ADSL/POTS splitter per port
....from Pinnacle
Click to expand...

http://www.itworx.co.za/d-link-wlan.htm has a pricelist of these Dslams.
Now dominic has Icasa type approved this stuff? :confused:

www.pinnacle.co.za and www.mustek.co.za imports directly from www.dlink.com
and they stock Dslams.
www.d-link.co.za could not tell me why they don't import it or if the stuff is Icasa approved.
Do we have dappermuise in our midst perhaps or has Icasa finally stopped
taking orders from Telkom?
 
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daffy said:
(quoted for truth)
VDSL2 is great, but at those prices, and with such restricted distances, It would work out better to run Fibre. Especially considering that to achieve those high speeds, you need 2 copper pairs (thats 4 wires, not 2)
Click to expand...

http://www.convergedigest.com/iptv/iptvarticle.asp?ID=21707
"..Bonded VDSL2 over two lines to deliver an effective data rate of 40 Mbps to subscribers up to 5,000 feet from a remote DSLAM. A single VDSL2 line can deliver 40 Mbps only up to 3,000 feet...."

I just noticed that out of 67000 page hits on Google this thread ranks as nr.9 with the search words "DSLAM" and "VDSL2".
http://www.google.co.za/search?as_q...as_dt=i&as_sitesearch=&as_rights=&safe=images
 
captainwifi said:
thut can't sell stuff without Icasa's permission. It places the IT world in a very difficult position. ... where pinnacle is selling a 48-port switch that can only
do a 100m over bulky cables C-com is selling a 48-port switch/router ... that can do 5km.
Click to expand...
Captain, you're confusing a few concepts in the above.

Firstly there is nothing illegal about selling & using DSLAMs in SA. What is regulated is the connection of these to a licensed public network (PSTN), for this you need ICASA Type approval for a praticular piece of equip. Naturally you also need a license if you are to provide it as service (to 3rd parties for profit).

So for example if you own a large plot/farm with multiple houses dispersed a couple of Km from each other, you could use ADSL to connect them. Put a (IP) DSLAM into the central one and string telephone grade wire to the others, terminating them with std ADSL routers. Viola, you've created a private long distance LAN using ADSL technology.

The other thing you're confusing is the ports on DSLAMs. The subscriber ports connect to telephone wire and run some form of DSL protocol over them (ADSL,ADSL2+, VDSL etc. whatever supported by the DSLAM). The trunk ports aggregate the traffic from the subscriber ports and ship it further onto another network.

DSLAMs come in 2 basic flavours, ATM & IP. Older ATM DSLAMs take the ATM cells from the subscriber ports and multiplex them into VCs on an ATM trunk port (e.g. 155 Mbps Oc3 fiber) which feeds them into a larger ATM switched network. Somewhere on the ATM network will be an ATM concentration router that will terminate the PPP session (riding within the ATM cells) and convert it to native routed IP.

Newer IP DSLAM (or mini-DSLAMs) integrate all of the above functionality into one box. The IP DSLAM has an integral ATM/IP router that terminates the ATM cells from the subscriber ports and forwards them out of an Ethernet trunk port (e.g. 100Mbbps/Gbps copper or fiber) as native routed IP.

In the plot/farm example above, you could concievably connect the IP trunk port of the DSLAM to another ADSL router connected to Telkom and you would still be fine. It is the router connected to Telkom that carries the ICASA Type approval. Obviously if Telkom caught you charging the other households for the connectivity they would get miff, however if its your mates/family sharing (on your property), I believe there's nothing they could do (much like parent's PC sharing with kids PC in same houshold).
 
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