About this question
It can be a security risk to have unwarranted open ports. So I ran nmap 192.168.0.1 to investigate if I had open ports on my home network, it turns out, I do:
PORT STATE SERVICE
53/tcp open domain
80/tcp open http
5431/tcp open park-agent
49163/tcp open unknown
This concerned me. However, upon further reading, I have discovered that running nmap from my home desktop does not obtain the actual open ports, but rather ports which are accessible from my desktop on the local network side; I'm interested in ports open to the Internet at large.
Therefore, I tethered my desktop to my phone Wi-Fi Hotspot and ran nmap again, this time I am outside of my local network, i.e. I am not connected to my home router provided by my ISP but rather connected to the Internet through my phone service provider. I ran nmap again, this time using the external IP Address of my home network. The output is as follows:
PORT STATE SERVICE
21/tcp open ftp
80/tcp open http
113/tcp closed ident
443/tcp open https
1935/tcp open rtmp
8080/tcp open http-proxy
There are still numerous open ports, which I was not expecting, as I am not running any servers and simply use my home network for Internet browsing. I do not think I should have any open ports. Why are these ports open to begin with? And should I be concerned/close to them?
