have you ever seen this before??

[Skillachi]

A business called me yesterday because of internet connection problems. First thing I did was called their ISP to find out if they were any work being done in the area they said no.

So I went over, while trouble shooting I notice there is internet access after pinging www.google.com at he CMD also I did a tracert and it went through fine. Suddenly I notice that there are 2 modems hook up together by way of a splitter.

There are wires coming from both modems join on to each other mainly from the telephone port on the modem. That situation had me questioning my self because I've never seen this before. Has anybody know why a technitian from a ISP would do this?? If so why? or is it just sloppy work?? or is it causing the internet and network problems??

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[Cambridge PC Support]

so you're saying there are 2 broadband modems on the same phone line?

are there ethernet cables running from both modems as well? if so, where do they go?

[Skillachi]

Originally Posted by Cambridge PC Support

so you're saying there are 2 broadband modems on the same phone line?

are there ethernet cables running from both modems as well? if so, where do they go?

Yes, 2 broadband modems on the same on the same ISP service cable/ethernet line from the wall.

Yes, cables running from both modems as well, with one ethernet cable providing internet access for 5 computers.

[tkrabec]

The modems could be in a "bonded" configuration in which their bandwidth are aggregated to give 1 larger pool of bandwidth. Login to the gateway and check the configs

[Skillachi]

Originally Posted by tkrabec

The modems could be in a "bonded" configuration in which their bandwidth are aggregated to give 1 larger pool of bandwidth. Login to the gateway and check the configs

What are the main benefits of (bounded configuration) and (draw backs) of it?

[DarDar]

i've never heard of that exact terminology but i have seen the same kind of setup based off of two different providers.

The advantage in that case was redundancy but it could also be for extra bandwidth, and depending on connection type, lower contention ratios.

The main downside would be in extra complexity and an extra point of failure. But usually if you are implementing something like this you would have better class of hardware. Not your usual consumer router. (unless you flashed it!)

[Ccomp5950]

If it has a splitter between them it's not a bonded setup, since for that to work it would have to be on 2 different phone circuits. Most likely what happened is they got ready to replace a DSL modem that broke with a new one and didn't unhook the old one, just plugged the new one in.

Remove modem#2, it's going to cause you problems when DHCP from #2 wins the race to hand out IP addresses. Also remove the multiple cat 5 cables connected between the two, it's really idiotic if I'm reading your diagram right.

They probably both have the same IP address too, which is going to mess with ARP

arp -a

You will probably find that the gateway IP address has more than one mac address listed which indicates the problem.

The reason I automatically assume #2 is the old one that needs to be removed is because the PC's are plugged into #1 and should always get IP addresses from it first unless some freak accident #2 can respond first (with the PC's plugged into #1 that's going to be rare).

When you remove one of the modems you are going to have to clear ARP tables to get it to work right, or you could simply reboot.

[parker.casey]

That setup is likely not giving extra bandwidth ... but if each modem is connecting on a separate line, it'd be in the old ISDN style.

[Skillachi]

Also guys notice that when I unplug one broadband modem the other still supplies internet access. There are 2 broadband modems, one is a Motorola the other a scientific Atlanta. Base on what I analyze the Motorola seems to be the main broadband modem. Whenever I disconnect the scientific Atlanta internet access is still available through the Motorola. But there is some telephone wires hook up to the scientific Atlanta Modem sharing it with the Motorola which you guys said its called (bounded configuration).

Also there is a Belkin router on the network which they had for a very long time. I think its also a source of some problems, so I told them to change it and I recommended the Netgear WNDR3700 RangeMax Dual Band router. Which is what I use at home with no problems what so ever.

So my question is, knowing that I will be setting up the new router for them which is the Netgear WNDR3700 RangeMax Dual Band is there any caution or steps that I'll need to be aware off before I start the process? I know for instance I will back up the Belkin router settings just in case something goes wrong with the new router setup any more tips?

By the way guys there are 5 computers in the building that I've seen so far and 5 printers. One huge office printer (similar to a xerox but its not a xerox its another brand) and one personal printer installed locally on a desktop. All these are on the first floor. The second floor has 3 desktops and 3 printers with a linksys switch connecting all of them. All those printers on the second floor has their own printer installed locally.

So you guys have any suggestion? please let me know am trying my best to brush up on my networking skills. Thank You all In advance.