What is a Router and what does it do?
Well, it depends who you ask. Strictly speaking a router is a device that routes network traffic between networks. However, thanks to the wonder of integrated internet gateway devices, the term router is often used to refer to these devices as well, even though they do a lot more than just routing.
Your typical household router (also called an integrated internet gateway, or SOHO router) does many jobs including:
- Router
- DHCP Server
- NAT Translator
- DNS Proxy
- WiFI Access Point
- Ethernet Switch
- Firewall
It may also do additional fancy things like
- File and Print server (using USB attached devices)
- POTS Telephone gateway
- Access Controls/Parental Controls
These devices are designed to serve as the all-in-one device to stand between your private network devices and your ISP's network or the Internet at-large. A common configuration you'll see is the 5 port device with WiFi. One of the 5 ports is designated as the WAN or Internet port. This is the connection to the outside network. The 4 other ports are your LAN ports for private devices. These are usually configured as an unmanaged switch, with the WiFi AP internally connected to this switch as well. You generally cannot configure these ports to connect to separate networks.
This type of device may be able to be used for show networks, but a show network typically doesn't need most, if any of these functions. The thing to watch out for is that the WiFi on these devices is generally not optimal for show usage. In most show applications, you don't want the access point to be in the same location as where the router needs to be located to connect to the rest of the network. Most of these devices don't handle multicast very well since it's rarely used in home networking applications.
If you want to use WiFi in your show, you're better off using a dedicated access point like the Ubiquiti Nanostation Loco M2 (NSLM2)
If you have the need for an actual router, or some of the other specific functions mentioned above, you're better off using a wired router device. One popular good choice is the Ubiquiti EdgeRouter-X. The ER-X has the ability to act as router, including VLAN support and the ability to control which each of the 5 ports does individually, or brigde some of them in a switch configuration. It also offers DHCP server (multiple instances if you need it), DNS proxy, NAT translation and firewall. All of which are highly configurable.
In most cases though, you don't even need a router, a plain old switch will work. And if that's all you need, that's all you should use. the extra functions in a router that you don't need could get in the way if you don't explicitly disable them.