Setting up a DSLAM - issues/suggestions?

[Bern]

So I am looking in to setting up a DSLAM for a residential building, but have never used DSL besides my home DSL line. I get DSLAM just extends L2 network and you can do some cool stuff like extend VLAN, QoS and the rest, but what I would really like to know is:

1. What sort of unforseen problems do you get in a real situation (i.e. the product reps don't tell you about)?
2. What vendors would you recommend?
3. Any other useful info in this regard?

Basically I think using the existing copper in the building is the quickest way to get the benefits of group buying to all the residents, ethernet or fibre to each apartment can be done later as it involves a much largere investment of capital and time.

All suggestions/stories/alternative ideas welcome

 

[Srack0verflow]

uhh i dunno, just guess it will be a serious amount of dollars

 

[MickeyD]

1. Who currently owns the copper in your building?
2. How will you connect your DSLAM to a switch on an operator's network?
3. What sort of maintenance contract will you have in place?
4. What write off period will you use when calculating cost per user per month?

 

[ambo]

MickeyD - the copper in the building is a building fixture (regardless of who installed it). It would thus belong to the owner of the building.

 

[Tinuva]

You need a DSLAM as well as a BRAS (which the PPPoE sessions terminate on), unless you just going to set up static routing in which case the BRAS can be replaced with a simple router as cheap as a mikrotik, however I think a mikrotik can also act as a mini BRAS if you wanna do it cheap.

 

[sburrell]

Theres no point setting up a DSLam for a building, The cost benefit ratio is not worth it, rather just rent high capacity from a local provider either via leased lines or another high cap distribution mediam, and set up a ras in the building. Then just run cat6 to each unit, or fibre to the edge of the elevator shafts.

 

[TheGuy]

Theres no point setting up a DSLam for a building, The cost benefit ratio is not worth it, rather just rent high capacity from a local provider either via leased lines or another high cap distribution mediam, and set up a ras in the building. Then just run cat6 to each unit, or fibre to the edge of the elevator shafts.

Well he already has phone cable running in the building so it would be a better bet to use a mini-DSLAM.

Last I heard you could get them form about R10K which will provide 48 ADSL lines. Then you just need a router to give out DHCP and to route traffic via your backbone.

I've even managed to connect a mini-DSLAM in the following way.

Telkom ADSL line - small ADSL router in Bridge Mode - DSLAM - client ADSL router - client PC.

The client adsl router will actually dial all way through to Telkom's BRAS and form a connection. You can also make unlimited PPPoE connections this way.

 

[sburrell]

Telkom will more than likely prevent u from using a dslam on any of the copper that will terminate onto their network, no matter who owns it.

 

[TheGuy]

Telkom will more than likely prevent u from using a dslam on any of the copper that will terminate onto their network, no matter who owns it.

There is no way that Telkom will now about it to them it will look like you have a normal router connected in bridge mode with all the PCs behind it dialing their own PPPoE sessions

 

[Tinuva]

Sharing 4mbit (10 if you lucky) between all those users wont be that nice...

 

[TheGuy]

Sharing 4mbit (10 if you lucky) between all those users wont be that nice...

True so you'll have to use multiple ADSL lines for this but I'm not sure how you are going to split the traffic.

 

[Bern]

uhh i dunno, just guess it will be a serious amount of dollars

R10k odd for a DSLAM with 48 ports, it is kind of like putting a switch in to a ethernet network

1. Who currently owns the copper in your building?
2. How will you connect your DSLAM to a switch on an operator's network?
3. What sort of maintenance contract will you have in place?
4. What write off period will you use when calculating cost per user per month?

Looking at some fibre options, Neofibre as a bottom option, then speaking to CoCT about their fibre and then some ISPs to see if I can backhaul on their network (and make sure I don't run traffic over a road myself - no ECNS).

Maintenance, still early days, depends on what the trustees want, write off period also falls under this one. I am also not sure if I will provide a full service or manage the equipment for them.

You need a DSLAM as well as a BRAS (which the PPPoE sessions terminate on), unless you just going to set up static routing in which case the BRAS can be replaced with a simple router as cheap as a mikrotik, however I think a mikrotik can also act as a mini BRAS if you wanna do it cheap.

Exactly, I can use any decent router or some OS system (was looking at PFSense as it has a lot of nice features including a captive portal for the wifi later)

Theres no point setting up a DSLam for a building, The cost benefit ratio is not worth it, rather just rent high capacity from a local provider either via leased lines or another high cap distribution mediam, and set up a ras in the building. Then just run cat6 to each unit, or fibre to the edge of the elevator shafts.

I want to go ethernet/fibre, but right now using a fairly cheap DSLAM and the existing copper in the building with a dedicated backhaul service is the quick win. It can then provide a case for the rest.

Sharing 4mbit (10 if you lucky) between all those users wont be that nice...

No way I will use Telkom, especially their ADSL, for backhaul. THe entire point is to be completely off their grid.

 

[Pada]

I find it quite silly to let each and every resident buy their own ADSL modem. There are also just so much more than can go wrong with ADSL compared to a CAT5e/6 network.
CAt5e/6 is limited to like 100m IIRC?

I think installing a CAT5e cable would cost about the same as a single ADSL modem.

If you're not going to have your own BRAS, then the residents are going to pay quite a lot for their Internet, since they won't be able to share like an uncapped account.
I suppose that many won't be able to afford Internet this way.

 

[ponder]

I don't reckon a dslam is the way to go.

You would be better off with something like Cisco's LRE (which they no longer do) etc. Most of them use a form of VDSL technology and run on normal telephone copper and they also look like normal switches. Oh, they're also significantly cheaper than a dslam.

 

[Roman4604]

Oh, they're also significantly cheaper than a dslam.

You do get cheapy ones, like this D-Link ... http://www.dlink.co.za/dslrouterdslam.php which is a IP DSLAM (integrated BRAS router). Not used this one myself, but assume it would work with both external Radius server or on-box auth accounts. They go for roughly R23K for 48 port & R13K for 24 port.

 

[ponder]

You do get cheapy ones, like this D-Link ...

Jip, only thing is how reliable are they seeing you will be serving many customers with it and I don't think you are going to get telco grade reliability on it. Then again you can always buy two and keep on as a spare.

 

[TheGuy]

I find it quite silly to let each and every resident buy their own ADSL modem. There are also just so much more than can go wrong with ADSL compared to a CAT5e/6 network.
CAt5e/6 is limited to like 100m IIRC?

I think installing a CAT5e cable would cost about the same as a single ADSL modem.

Really? Installing CAT5 into a building can easily cost you 60K.

 

[Pada]

Really? Installing CAT5 into a building can easily cost you 60K.

Thanks for the response.
This all depends on how big the building is, if it already has trunking in place, etc.

The labour costs would most likely be more than the cabling costs.

I just made a suggestion, but without knowing how many residents are in the building, or how big the building is, it is near to impossible to guess how much it'll cost for a CAT5 option

Update:
Can't you turn the copper wires into like a 10Mbps Ethernet cable instead?
I'd guess that with this you will run into interference problems.

 

[MickeyD]

MickeyD - the copper in the building is a building fixture (regardless of who installed it). It would thus belong to the owner of the building.

Nope, not necessarily. If Telkom installed the cable it belongs to them, unless they were paid to install the cabling as a once off lump sum.

 

[Bern]

I find it quite silly to let each and every resident buy their own ADSL modem.

The idea is to switch the current Telkom ADSL residents over first, so cheapest (considering they have a modem already) and quickest would be the DSLAM option. Noted I was thinking of maybe using PFSEnse for the BRAS, but will also consider various options.

I don't reckon a dslam is the way to go.

You would be better off with something like Cisco's LRE (which they no longer do) etc. Most of them use a form of VDSL technology and run on normal telephone copper and they also look like normal switches. Oh, they're also significantly cheaper than a dslam.

Problem is then existing ADSL modems can't be used, so total cost may not work out so great. Its more of a phase one I am looking at for the DSLAM, not the final solution.

Jip, only thing is how reliable are they seeing you will be serving many customers with it and I don't think you are going to get telco grade reliability on it. Then again you can always buy two and keep on as a spare.

Ja, my thinking was have a spare handy and make sure it is powered via a good UPS.

I would prefer to install Cat6 in to each unit, but still need to assess the site to see about viability of this, you never know with old buildings.

Roman4604, was actually looking at that D-Link and the Draytek units. Definitely going to have an external Radius server hosted in a more secure location, probably have two for redundancy.

So what kind of issues do these DSLAMs give? I am really interested to know if they have many random issues or if they generally work. We are talking close to 10 storeys and 25 units per floor.