My router has 4 LAN ports and they are all occupied. How can I increase the capacity of that router?
Buy a network switch if you have constraints for switching to a router with a wireless access point.
A network switch is usually a 4/8/16/48-port 802.3 (Ethernet) device that extends the broadcast domain of your network. Most off-the-shelves consumer switches do not require much configuration and is straightforward to set up.
To complement Jin's answer, if you have any old routers laying around they are also perfectly capable of functioning as switches. You would usually do the following to turn the router into a switch:
- Disable DHCP service on it.
- Assign a static IP to it that's outside the IP range given by your first router's DHCP service but still within your network's subnet. This step provides a way for you to get into your second router later if you need.
- Connect a regular ethernet cable from your first router's lan to your second router's(now a switch) lan port.
Note that routers typically have less lan ports compared to a full-fledge switch but this provides another way to expand your network. If the second router is wifi capable it can also double as a secondary Access Point to expand your wifi coverage.