DS3 or DSL over 4 twisted pairs

martin.roy · ‎10-21-2005

Hi,

I have a challenge. I have a small campus that I need to connect over a 8km (5 miles) radius. There is no fiber available between buildings and wireless is not an option because of the extreme weather in this environment. All I am left with is four pairs between the hub and spokes.

I am thinking about installing a DSLAM at the hub with c800 series routers at the spokes. But I will be over the 4.5km distance of the technology in some cases. Besides, the density (about 20 spokes) doesn't quite justify a full DSLAM. Tut Systems (www.tutsys.com) has a product that might do the trick (MXL-2300) but I would rather stick with Cisco products.

The other option (which is preferred if possible) would be to get a DS3 over copper solution. Normally, I would just ask the telco to provide the CO gear but in this case the telco refuses to play ball so we are doing our on thing. The question is, what kind of gear do I need to get DS3 speed?

Thanks

Martin

binoyjosephstanly · ‎10-22-2005

Hi

martin ur issue is u want to establish a link between ur other depts which is in same campus but around 8 km distance.whats the speed u want to achieve.

i can suggest a solution with G.SHDSL.for achieving this you should use routers. lets say you are going to connect to a dept. which is 3 km away.

you can deploy this in a back to back fashion.

you have to lay the cable 2 pair copper( 4 wire)from one location to another.

one router at central site you can configure as central office(CO) and othjer router at the branch configure it as branch router.

you can use any router which can support a G.SHDSL card.

Part no of this dsl card is

WIC1-SHDSL-V2=

in cisco router OS should be 12.0.

how many branches you have. if you can arrange 2 routers and 2 wic cards you can do a pilot project.

and this will give you a band width of 4.6Mbps.which is equivalent to 2 E1 links.

you can think about this, if you want more details about this i can give you. Please let me know.

Regds

Binoy.

martin.roy · ‎10-23-2005

Hi Binoy,

Thanks for your recommendations. However I have a few sites as far as 8km from the hub so DSL will not work that far (unless I am not up to date on the technology).

I have about 20 spoke sites with one hub.

Martin

binoyjosephstanly · ‎10-23-2005

Martin

laying cables to around 8km distnace is surely a huge task.as Mr.scott suggested you can go for a wireless solution.You can use equipments like 1300 or 1400 wireless bridge.

my opinion is go for 1400 wireless bridge with external antenna.in this case you have to choose some high gain externnal antenna.may be 12 dbi or 13.5 dbi.If you are thinking abt this just go for a site survey.you have to check the LINE OF SITE, or atleast the fresnnen zone.

mmay be you have to take approval for using high gain antenna.before start working on this just have a word with "TRA".

you can think about this, you have to depoly this in point-to-multipoint fashion.

Regds

Binoy.

Regds

Binoy

scottmac · ‎10-23-2005

Short of satellite, microwave, laser (ala Canon CanoBeam), or 802.11 wireless, I believe you're stuck.

There are some ISM band microwave equipment that can do 1-3 DS3s (Sylink used to have stuff, but I'm not sure they're still around), VSAT/USAT (lots of latency) would work for connectivity, but not at anywhere close to DS3 bandwidth (~T1 .... maybe up to six meg ... and expensive).

The Canon CanoBeam can do up to OC3, maybe a gigE by now up to five miles, but you have to have fairly clear air and East/West spokes are prone to errors from the rising / setting sun.

802.11 point-to-multipoint probably is your best bet. Extreme conditions can be overcome (usually) with a NEMA enclosure (can be heated or airconditioned). The antennas or dishes can be conditioned for extreme weather (usually some flavor of radome).

802.11 can get you out to 8km pretty easily, but again, not quite DS3 speeds.

Long Reach Ethernet is only good to ~5000feet, usually at ~one meg ... not likely to be a good option for you.

I'm 99.99 percent certain you can't drive copper to those lengths, and especially at those speeds (DS3 is usually only good to ~650 feet, over coax).

I believe your stuck with some flavor of wireless (trencing fiber would be your next best option, IMHO).

Good Luck

Scott

martin.roy · ‎10-25-2005

Hi Scott,

Wireless or microwave is out of the question because this installation will take place in the Arctic (read frequent -60 and below weather). Politics are also playing a role in this :(

However, it doesn't have to be DS3. Inverse MUX of T1s would do the trick but what is the max distance for this kind of scenario? Also what hardware would I need at each end to make it work?

Thanks

scottmac · ‎10-28-2005

I'm pretty sure you can't even drive *one* T1 that far (most require a repeater ~6000 feet).

There may be some proprietary stuff .... check Black Box (www.blackbox.com), Canoga Perkins (mostly fiber stuff though, I think) (www.canoga.com) ...

Try a google on "line drivers," "line powered amplifiers" etc ...

That's a pretty long haul for copper, getting anything through is gonna be tough.

Good Luck (stay warm)

Scott