CM1200 not working with wireless routers

[tanviper]

I went from cox's 150 internet service to their gigablast service yesterday. I knew I was going to need a new modem as my old one wasn't 3.1. I purchased the Netgear CM1200 and got it setup. My computer--which it plugged directly into it--gets online. My linksys AC8500 wireless router refuses to work with this new modem, and I've tried every port on the back of the CM1200 modem, verified the modem is plugged into the yellow "internet" port on the back of the router and even tried different cat 5e cables. So, I thought, maybe it's this router, and went and bought a new linksys AC2200 router to swap it out with. It's doing the same thing. I can't get either of these 2 linksys wireless routers to work. I've reset back to factory settings both routers and even the CM1200 while trying to troubleshoot this issue. I can connect directly into the wireless routers if I plug my computer into either one, but they won't PING when connected to the CM1200. All my 4k Firesticks, blink cameras, garage door, NEST, laptops, etc need wireless, and right now I'm plum out of ideas. Can anyone help? 

[plemans]

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@tanviper wrote:

I went from cox's 150 internet service to their gigablast service yesterday. I knew I was going to need a new modem as my old one wasn't 3.1. I purchased the Netgear CM1200 and got it setup. My computer--which it plugged directly into it--gets online. My linksys AC8500 wireless router refuses to work with this new modem, and I've tried every port on the back of the CM1200 modem, verified the modem is plugged into the yellow "internet" port on the back of the router and even tried different cat 5e cables. So, I thought, maybe it's this router, and went and bought a new linksys AC2200 router to swap it out with. It's doing the same thing. I can't get either of these 2 linksys wireless routers to work. I've reset back to factory settings both routers and even the CM1200 while trying to troubleshoot this issue. I can connect directly into the wireless routers if I plug my computer into either one, but they won't PING when connected to the CM1200. All my 4k Firesticks, blink cameras, garage door, NEST, laptops, etc need wireless, and right now I'm plum out of ideas. Can anyone help? 

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That's your problem right there. Even though the CM1200 has 4 ports, your isp only supplies a single ip address. And your computer is using it. If you're on a business setup, the isp can supply more but most aren't as its more expensive. Port 1 is used for connections to router. You can use port 1 & 2 if your router supports wan port aggregation but I don't think your linksys does. 

So unhook your computer from the modem, reboot it, and hook the router up to it.

[tanviper]

". Even though the CM1200 has 4 ports, your isp only supplies a single ip address"

I did as you suggested, and it's working now. There's now a new issue. My connected speed dropped by 2/3. I was getting 900 megs testing out to fast.com when my computer was plugged into the CM1200, now that it's going through the AC3500,i'm getting 300. Is there something else I need to look at?

Correct me if I'm wrong (my network know-how is limited here)

1) ISP assigns IP address to you

2) I THOUGHT it was assigned to the cable modem since you have to give the ISP (Cox) the serial number, model #, etc.. off the modem.

3) CM1200 has 4 ports on the back, i THOUGHT the modem assigned an interanl IP to those ports so you can have 4 devices directly connected to your CM1200 without them "grabbing" the ISP assigned IP adddress.

4) What good are the extra 3 ports if I can't plug my computer into them?

5) My CURRENT set up is CM1200 with only 1 thing plugged into it (the AC3500) and then everything plugged into it.

6) I'm also using a smaller DGS 105 switch (it's a unmanaged, 5 port Gigabit switch from linksys)  for a few smaller things since my AC3500 doesn't have enough ports in the back (it's using one of the ports on the AC3500 and a few items are plugged into the DGS 105.

7) computer is plugged into the AC3500, not the DSG 105 (just want to be clear)

[plemans]

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@tanviper wrote:

". Even though the CM1200 has 4 ports, your isp only supplies a single ip address"

I did as you suggested, and it's working now. There's now a new issue. My connected speed dropped by 2/3. I was getting 900 megs testing out to fast.com before switch all of this, now i'm getting 300. Is there something else I need to look at?----Your router. If you were getting full speeds from the modem with it directly connection and then speeds drop when you go modem----router----pc. The router is what's limiting it. Not sure about the linksys settings but I'd check with linksys as to why their device is slowing things down. Sometimes is qos, parental controls, etc thats slowing speeds. 

Correct me if I'm wrong (my network know-how is limited here)

1) ISP assigns IP address to you----Most isp's only assign a single ip address. for consumer connections.

2) i THOUGHT it was assigned to the cable modem since you have to get ISP serial number, model, etc..

3) CM1200 has 4 ports on the back, i THOUGHT the modem assigned an interanl IP to those ports so you can have 4 devices directly connected to your CM1200 without them "grabbing" the ISP assigned IP adddress---Sadly, no it doesn't work this way. 

4) What good are the extra 3 ports if I can't plug my computer into them?----not a whole lot if you're ISP doesn't assign multiple IP addresses per account or if you don't have a router that has wan link aggregation. I  usually recommend the cm1000 or cm1200 for most home users. they're the same basic modem internally. 

5) My CURRENT set up is CM1200 with only 1 thing plugged into it (the AC3500) and then everything plugged into it.---that's how it should be. 

6) I'm also using a smaller DGS 105 switch for a few smaller things since my AC3500 doesn't have enough ports in the back (it's using one of the ports on the AC3500 and a few items are plugged into the DGS 105.----correct. It should go modem----router----switch/devices. 

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[tanviper]

"I  usually recommend the cm1000 or cm1200 for most home users. they're the same basic modem internally. "

should I take the Cm1200  back and get the cm 1000 then? There is a price difference and if they are the same with the exception of the ports in the back--which I'm now not using--then is there any advantage to keeping the CM1200 over a CM1000?

[plemans]

Sorry, I mistyped. I usually recommend the cm1000 or cm1100. I'd look at either of these. The only benefit to going more than the cm1000 is if you plan on using port aggreation or getting speeds >1gig. Some ISP's over provision their modems 20% (not sure about yours) so some like the wan port aggregation for this. 

CM1000-single port, gigabit

CM1100-2 port for wan port aggregation. Up to 2gig speeds with wan port aggregation. Or for isp's that supple 2 ip addresses

CM1200-4 port, 2 can be used for wan port aggregation. or for isp's that supply up to 4 ip addresses. 

[antinode]

> 1) ISP assigns IP address to you

   Define "you".  _You_, personally, do not get an IP address.

> 2) I THOUGHT it was assigned to the cable modem since you have to give
> the ISP (Cox) the serial number, model #, etc.. off the modem.

   No.  The ISP-assigned IP address goes to the device which is
connected to the modem, not to the modem itself.

> 3) CM1200 has 4 ports on the back, i THOUGHT the modem assigned an
> interanl IP to those ports [...]

   No.  A modem can't assign any IP address to anything.  That's what a
router does.

> 4) What good are the extra 3 ports if I can't plug my computer into
> them?

   To you, probably none.  Your ISP could, in principle, use them to

give you multiple external/public IP addresses, or for aggregation to

give you higher speed.

> 5) My CURRENT set up is CM1200 with only 1 thing plugged into it (the
> AC3500) and then everything plugged into it.

   Ok.

> 6) I'm also using a smaller DGS 105 switch for a few smaller things
> since my AC3500 doesn't have enough ports in the back (it's using one of
> the ports on the AC3500 [...]

   Ok.

   For a good time, visit http://netgear.com/support , put in your model
number, and look for Documentation.  Get the User Manual.  Read.

[FURRYe38]

I recommend you check out a CM1100, it has just two ports in back, supports LAG if you want that,  and 1G connections:

https://community.netgear.com/t5/Orbi/Orbi-RBR50-is-not-supporting-900Mb-on-the-WAN-to-LAN-test/m-p/...

Some get confused by the CM1200 having 4 ports in back which some mistakenly take or having a built in router. Any NetGear CM model modem does not have a built in router, period. ISP WAN IP address will pass thru the modem at such time when a device or router gets fully connected. There is a temp IP address assigned to the device or router. however soon after, the WAN IP addresss from the ISP will engage and be seen on the WAN side of the router or network adapter of the device connected to the modem. 

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@tanviper wrote:

"I  usually recommend the cm1000 or cm1200 for most home users. they're the same basic modem internally. "

should I take the Cm1200  back and get the cm 1000 then? There is a price difference and if they are the same with the exception of the ports in the back--which I'm now not using--then is there any advantage to keeping the CM1200 over a CM1000?

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[JasGr81]

I was using a switch but wasn’t getting the speed that I was previously getting so I removed the switch completely and the speeds went back up around 115 Mbps. With the switch I was only getting around 70 Mbps.

[FURRYe38]

Is the switch rated for 100Mbps or 1000Mpbs connection rates? 

Also the switch should be installed after a router, not between the modem and router. 

[Justin_UT79]

I know this thread is old, but I couldn't help but comment. Antinode, I am sorry man, but your responses to the OP were so condescending! Compare what you wrote to what plemans wrote and you will see exactly what I mean... Especially your response to tanviper’s first statement about the assignment of an IP address.

[FURRYe38]

Any progress on this? 

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@JasGr81 wrote:
I was using a switch but wasn’t getting the speed that I was previously getting so I removed the switch completely and the speeds went back up around 115 Mbps. With the switch I was only getting around 70 Mbps.

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