Do I need a router?

Networking Networking Hardware
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I'm setting up my network equipment in my home.
I have a TP-Link Cable Modem, TP-Link 8 Port Switch and TP-Link WAP.

My plan was to connect the modem to my 8-port web managed switch and then connect my AP to my switch.
But, I've run into a problem - when I connect my laptop to my switch in an attempt to configure everything I pull what appears to be me comcast (public?) IP address rather than an internal network address similar to 192.168.x.x.

In this scenario, would I need a router in addition to my other equipment?

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Maybe

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Thanks!

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Glad I could help.

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I take it that the TP-Link Cable Modem was not provided by your internet service provider. In that case you probably either need to setup a Pfsense box or get an combination modem router. I don't know for sure but it sound like the TP-Link Cable Modem doesn't included a router. I would call your internet service provider to check and see if the TP-Link Cable Modem is compatible with there network before I spent anymore money. If it is ask them how to properly set it up. You don't want to talk to the person you are doing to get on the phone. Tell the person on the phone you want to be transferred to a level 2 technician. or you could call the manufacturer of the modem.

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Yep - non ISP provided.
I already had my modem and old router/AP/switch-all in one set up before I switched over to this set up, so the modem is compatible.
I'm looking toward building a pfSense box, but wasn't sure why I might need it.

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a modem that is not a modem/router combo only forwards the public IP (from ISP), to your router, which runs its own DHCP server and NAT wall.

If using a layer 3 switch, you need to either have it use the existing DHCP, or have it run a DHCP server of its own; some do this.

So to answer your question, no you don't need a router; you need your own DHCP server (which is something routers do).

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So basically Pfsence acts like a software layer 3 switch?

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I am not familiar with Pfsense (hoping to change that), but from what I gather yes it essentially is, but you can more or less tweak it to what you need.

tldr; yes.

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i wouldn't. they'll only tell you "no, you need to rent one from us."

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It depends on the internet service provider or who you know at the internet service provider. Time warner use to have a list of modems that were supported for there network, but since Timer Warner doesn't exist anymore I don't know if they will let you use anything but their own equipment. Of course the TP-Link Cable Modem probably doesn't have a built in DHCP server and NAT wall, so it won't access the internet unless it's attached DHCP Sever with a Nat wall. The best option the original poster has without spending anymore money is to contact the manufacture of the modem ans find out if the TP-Link Cable Modem has built in DHCP Server with a Nat wall.

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Thank you so much for that information! Helps a ton.
That tells me what direction I need to go in.

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He’s exactly right. Your modem isn’t giving individual devices on the network an internal IP, because it isn’t running DHCP. A router of some sort will. pfSense will do the job well.

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You need a router. That modem will not do any DHCP work, nor will it provide firewall duties, or anything a router does. Furthermore, your modem locks itself to a single mac address per power-on. Your switch is not going to be sufficient for doing that.

You could go PfSense or you could go with something like a Ubiquiti EdgeRouter. You just need something to sit between your modem and your switch that will do all the typical router duties. Your network should go:

Coax in -> modem -> router -> switch -> wired devices and Access Point

Guys, a generic 8 port TP-Link switch is definitely not a level 3 switch. Comeon now.

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Yup, like Caveman pointed out, you def need a router or firewall thing like pfsense.
If you grab an off-the-shelf router, it will most likely have 4 LAN ports or so, so you won’t need the switch. You can plug your access point into it and run lan cables to your other devices.
If you have an old computer you don’t mind running 24x7, have a play with pfsense.

The internet is an openly hostile place. If you connect a computer directly to it, many devices will automatically scan it for vulernabilities and attempt to subvert it for their needs. Most ISPs will block this for you, but that is not guranteed.

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If you want to connect your local network to the internet then you need a router. That’s what a router is, it switches traffic between networks. If you only have a single device then you don’t need one.

Dhcp and firewall is separate to that function, you want those things too. You can of course use a firewall on your device to protect you from the internet but you need a firewall with NAT if you want to share a single public IP with multiple devices on your network. All this stuff you want is bundled together in what is called a router but they’re all different functions.

Long story short, anything which is commonly called a router does all the things you need, but you do need one.

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