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Dan
01-21-11, 06:02 PM
I had great speeds for a couple years with a comcast modem and D-Link DIR-615 router,then 2 weeks ago I returned the modem for a telephony/modem,because I bundled my landline with comcast,so now I have the modem "Arris" which has telephone and internet,it all works,but ! now I get DL speeds from speedtest.net of about 5 or 6 mb,I hade 15 to 19mb before I swapped out modems,

if I bypass the router and go directly to my pc I get 18 or 19 mb down,but when I go through the router it only gets about 5mb down.

I have the latest firmware :
Current Firmware Version : 3.13NA
Current Firmware Date : Tue, 14, Sep, 2010

so my question is this, is there a setting in my modem I need to change ? or is this router going bad ? maybe I should get a new one ?

PsykoPenguin
01-21-11, 07:54 PM
I had great speeds for a couple years with a comcast modem and D-Link DIR-615 router,then 2 weeks ago I returned the modem for a telephony/modem,because I bundled my landline with comcast,so now I have the modem "Arris" which has telephone and internet,it all works,but ! now I get DL speeds from speedtest.net of about 5 or 6 mb,I hade 15 to 19mb before I swapped out modems,

if I bypass the router and go directly to my pc I get 18 or 19 mb down,but when I go through the router it only gets about 5mb down.

I have the latest firmware :
Current Firmware Version : 3.13NA
Current Firmware Date : Tue, 14, Sep, 2010

so my question is this, is there a setting in my modem I need to change ? or is this router going bad ? maybe I should get a new one ?

What I'm thinking is that you might be going through a double firewall. Any idea if your modem has a firewall built into it?
If so you'll want to disable the firewall within the router if there is a firewall there.
Also might want to disable the modem firewall if you have a software firewall on your computer.
2 or more firewalls = conflict

another thing Im thinkin if that doesn't help is you need to set the MTU on your router.

Sava700
01-21-11, 08:27 PM
Sounds like you are in a double NAT situation. Just shut off the firewall within the dlink and verify, the default MTU on the router is already set to broadband settings.

Dan
01-21-11, 08:43 PM
thanks for the replies and I will check all that,but why did the router work for high speeds with the other modem ? all i did was unplug one modem and plugged in the new one.

PsykoPenguin
01-21-11, 09:03 PM
thanks for the replies and I will check all that,but why did the router work for high speeds with the other modem ? all i did was unplug one modem and plugged in the new one.

it is quite possible the other modem had the firewall disabled or didnt have one at all and thus there was no conflict.
this new modem however may have a firewall and if it does it's turned on and is conflicting with your routers firewall.
Thus decreasing your internet speeds.
Though seeing as directly connected to the modem gives you your normal speeds there'd be no need to turn off your modem firewall as I said previously.
However if you're still having problems I'd say reset the router if you haven't already, a simple power reset will do.
if the problem persists you do a factory reset and work your way from there.

Dan
01-21-11, 09:31 PM
can a router go bad on the speeds but still work ?

Sava700
01-21-11, 09:35 PM
can a router go bad on the speeds but still work ?

Yes a router can go bad... but yeah I think your double firewall running here.. just disable it in one of them.

Dan
01-21-11, 09:54 PM
Yes a router can go bad... but yeah I think your double firewall running here.. just disable it in one of them.

well,I turned off everything in the "firewall settings" page in the router that I see,and the MTU is 1500 and I have reset the unit to factory defaults and with the pin hole on the back.
I will have to go to the modem without the router and see what settings are in there,how do I find the address of the modem ?

CableDude
01-21-11, 09:58 PM
well,I turned off everything in the "firewall settings" page in the router that I see,and the MTU is 1500 and I have reset the unit to factory defaults and with the pin hole on the back.
I will havew to go to the modem without the router and see what settings are in there,how do I find the address of the modem ?

http://www.ehow.com/how_5956095_log-arris-cable-modem.html

PsykoPenguin
01-21-11, 10:10 PM
Yes a router can go bad... but yeah I think your double firewall running here.. just disable it in one of them.

also on that note, it doesn't matter which one you disable just as long as one is disabled.
on a personal level I'd turn off the router firewall rather than the modem firewall.

Dan
01-21-11, 11:34 PM
there is no firewall info or settings or anything firewall in the modem.
I'm going to try a new router tomorrow to see if that's it.

YeOldeStonecat
01-22-11, 07:42 AM
The Arris is not a combo modem/router, it's just a bridged modem. In your voice mail you said you thought you got it back to speed...but it's not? Since you switched from DSL to cable, does your router still have the MTU setting set to 1492, or auto? Try to find that setting for the MTU and manually change it to 1500. I'm out for the morning to a funeral, then wife has a thing at a home show at the casino..so I'll be back late afternoon if you want to try to hook up again and I'll remote into your PC and check the routers settings.

Sava700
01-22-11, 10:27 AM
there is no firewall info or settings or anything firewall in the modem.
I'm going to try a new router tomorrow to see if that's it.

I'm curious as the exact model modem your using, but considering certain types it may be different from what I'm thinking. You've reset the router settings to default and you've verified already that the MTU is set to 1500 so we know this is ok. I guess since your already going to get a new router lets see what that does for now.

Dan
01-22-11, 10:31 AM
The Arris is not a combo modem/router, it's just a bridged modem. In your voice mail you said you thought you got it back to speed...but it's not? Since you switched from DSL to cable, does your router still have the MTU setting set to 1492, or auto? Try to find that setting for the MTU and manually change it to 1500. I'm out for the morning to a funeral, then wife has a thing at a home show at the casino..so I'll be back late afternoon if you want to try to hook up again and I'll remote into your PC and check the routers settings.

I did'nt switch from dsl,I had the same comcast "performance" internet,have had for a couple years,the only thing I changed was I added the phone part,

the PM I sent you looked like I was saying modem/router,but it was just a combo question,I know the modem does not have a router,

and the router for sure has the mtu set to 1500.and no,the speeds are about 6 dn with the router,and without it dl is 19 !

Dan
01-22-11, 10:33 AM
I'm curious as the exact model modem your using, but considering certain types it may be different from what I'm thinking. You've reset the router settings to default and you've verified already that the MTU is set to 1500 so we know this is ok. I guess since your already going to get a new router lets see what that does for now.

the modem is a " ARRIS TM722",there is no settings for the firewall that I can see.and yes,the router is set to 1500.

Philip
01-22-11, 11:40 AM
The Arris models are listed on SG as well, along with IP addresses, etc.: http://www.speedguide.net/broadband-list.php?brand=37

Dan, how far are the modem and router from each other ? (I'd try to keep them a couple of feet apart). Many devices are very susceptible to EMI, so try to keep the router away from power supplies, modems, fluorescent lights, coiled Cat5 cables, etc.

Dan
01-22-11, 12:59 PM
The Arris models are listed on SG as well, along with IP addresses, etc.: http://www.speedguide.net/broadband-list.php?brand=37

Dan, how far are the modem and router from each other ? (I'd try to keep them a couple of feet apart). Many devices are very susceptible to EMI, so try to keep the router away from power supplies, modems, fluorescent lights, coiled Cat5 cables, etc.


mmmm,interesting,they are right next to each other.I'll move one of them.

Dan
01-22-11, 01:19 PM
with the router :(
http://www.speedtest.net/result/1123050477.png (http://www.speedtest.net)
without the router
http://www.speedtest.net/result/1123054635.png (http://www.speedtest.net)

Sava700
01-22-11, 04:52 PM
The router may be dying off..it does happen. Are you plugging into the same port? what else is connected to the router?

I looked through the whole manual and didn't see anything that would revert to default to cause this.

ftp://ftp.dlink.com/Gateway/dir615_revC/Manual/dir615_revC_manual_300.pdf

Dan
01-22-11, 06:18 PM
well,I just picked up a linksys/sisco E2000 and got these speeds right away on my desktop
http://www.speedtest.net/result/1123404537.png (http://www.speedtest.net)
and this on my wireless LT
http://www.speedtest.net/result/1123429729.png (http://www.speedtest.net)

Dan
01-22-11, 07:29 PM
more,different server
on my desktop
http://www.speedtest.net/result/1123467368.png (http://www.speedtest.net)

on my laptop(wireless)
http://www.speedtest.net/result/1123462541.png (http://www.speedtest.net)


it's definitely better :)

http://www.speedguide.net/speedtest/results_img.php?test=3184166 (http://www.speedguide.net/speedtest/results.php?test=3184166)


I just got this now
http://www.speedtest.net/result/1124252686.png (http://www.speedtest.net)

even got better better on my iPhone
http://www.speedtest.net/iphone/87314148.png

Sava700
01-22-11, 08:05 PM
so must have been the router then... I wonder if it was truly bad or not.

Rainbow
01-22-11, 11:04 PM
Don't mean to latch on But My sons GF has the same comcast setup and wanted to add wireless. She bought a linksys cisco router but I cant get it to work in one of the outlets in a room.
If I connect it right at the output of the modem the wireless works but it wont pass the wired part thru one of the numbered ports.
Does she need a special type of router to do the combo telephony internet stuff?

YeOldeStonecat
01-23-11, 08:21 AM
If I connect it right at the output of the modem the wireless works but it wont pass the wired part thru one of the numbered ports.
Does she need a special type of router to do the combo telephony internet stuff?

No...the phone breaks off before the wireless, the cable modem passes internet through standard ethernet.
Describe the setup more where you say it won't pass the wired part?

Rainbow
01-23-11, 09:18 AM
Ok, Its a newer home with all the wiring for the rooms coming to a box in the basement that everything is just thrown into. There is a splitter for the rg6 tv side, there is the modem , there is a terminal block that all the ethernet wires run into from the rooms, then there is a small square cat 5 wall jack that the modem plugs into with the other end going up into the wall.
If I put the router in one of the rooms I get nothing, no wired or wireless.
If I put the router in the basement between the modem and the cat5 wall jack then the wireless does work and I thought all was well but they called back and side none of the wired outlets in the rooms work now. I plugged the modem into the internet port of the router then plugged number 1 on the router to that cat5 wall jack.
I have never worked with this system before is there a setting I'm missing?
Do I need to clone the mac on the router?
They also said they get a red x over the internet connection down by the clock on the wired computers.

I believe it is the full comcast digital voice with tv and internet but they had no wireless which is why we are trying to add the router

Rainbow
01-23-11, 09:32 AM
Oh and the main box in the basement says Greyfox systems on it. It has a built in 120 volt receptacle and the ethernet terminal block with about 12 jacks inside. The modem and tv splitter and cat5 wall jack are just tossed inside.

YeOldeStonecat
01-23-11, 02:38 PM
Ok, Its a newer home with all the wiring for the rooms coming to a box in the basement that everything is just thrown into. There is a splitter for the rg6 tv side, there is the modem , there is a terminal block that all the ethernet wires run into from the rooms, then there is a small square cat 5 wall jack that the modem plugs into with the other end going up into the wall.
If I put the router in one of the rooms I get nothing, no wired or wireless.
If I put the router in the basement between the modem and the cat5 wall jack then the wireless does work and I thought all was well but they called back and side none of the wired outlets in the rooms work now. I plugged the modem into the internet port of the router then plugged number 1 on the router to that cat5 wall jack.
I have never worked with this system before is there a setting I'm missing?
Do I need to clone the mac on the router?
They also said they get a red x over the internet connection down by the clock on the wired computers.

I believe it is the full comcast digital voice with tv and internet but they had no wireless which is why we are trying to add the router

By your whole description, it sounds like the wiring is not proper...router on the outside or on the inside....wiring does not sound correct.
MAC spoofing is bandaid approach, I prefer to do it properly. The cable modem memorizes the MAC of the first device connected to it. Say you test your new setup with your laptop...it will learn the MAC of your laptops NIC. If you want to then put a router in place..you need to get the cable modem to learn the MAC of the WAN port of your router. Simple...unplug the power from the cable modem and leave it unpowered for 30 seconds or so. Now uplink your router to the cable modem..router powered on. Now power up modem..allow to synch up..and it will see and learn the MAC of your router. Once synched up (about 30 seconds) power cycle your router so it will now pick up a proper public IP address..and correct DNS. Now boot up a computer from behind your router...should be online.

For the MTA (voice ip modems)...you have one addition to the above. They have a little battery in them..so your phone works in case of power outage. A little cover on the bottom of the Arris...pull it, slide battery out. Without doing this..simply unplugging the power from your modem...it will still be powered by the battery and flushing the MAC will be fruitless. (insert caution, while doing this, you have no phone for this 30 second maneuver to make a 911 call if needed...so don't have the kids playing with chainsaws while doing this)

Rainbow
01-23-11, 04:48 PM
Ok will try that.
I don't know about the wiring but if comcast did it , its a terrible job. The thin metal cover on the box was bulging and when i took it off the modem and rg6 splitter fell out.
I power cycled the router but never did power cycle the modem.
I mounted the router to the back of the box with double sided tape and the wireless signal is great 2 floors above so that part works great. I just dont understand why it wouldn't connect on the wired side.

Dan
02-19-11, 04:25 PM
this new router is really great,it is working fine.

http://www.speedtest.net/result/1165079708.png (http://www.speedtest.net)