Open ports on router

Question

I have a TP-Link TD W8970 modem/router. Just for fun i tried to perform a port scan on it. I found this:

$ nmap -p 1-65535 -n 192.168.1.1

Starting Nmap 6.00 ( http://nmap.org ) at 2016-01-21 16:17 CET
Nmap scan report for 192.168.1.1
Host is up (0.0097s latency).
Not shown: 65530 closed ports
PORT      STATE SERVICE
23/tcp    open  telnet
80/tcp    open  http
1900/tcp  open  upnp
7547/tcp  open  unknown
50393/tcp open  unknown

Nmap done: 1 IP address (1 host up) scanned in 54.03 seconds

Aside from ports 23 80 1900 (even though i have upnp disabled), what about the other ports?

Answer 1

TCP 7547 is used for CPE WAN Management Protocol (CWMP) any may only be exposed to your internal interface (run a scan on your public IP from outside your network to see if this service is exposed to remote actors). This management protocol can sometimes be disabled in the management GUI, other times it's possible only at the command line (Telnet or SSH if your device supports it).

TCP 50393 might be Apple's XSAN protocol. Do you have any Apple devices on your network, particularly Time Machine? Was your router marketed as supporting USB attached sharing / NAS functionality? As before, scan against your public IP from outside your network to ensure this isn't exposed to the outside world, but I'm pretty sure this is open as a network storage feature for your router.