OS X: How to lock down these frivolous protocols! I ran a port scan on my Mac (OS X 10.9.4 if its relevant) and i realised all these random protocols with next to no explanation on the internet.

2 of the most unusual protocols include ndl-aas and dec_dlm, And i recall that keeping track of these open ports on your computer is generally a good idea to maintain your computers security.

So my question


What are the purposes of the protocols ndl-aas and dec_dlm?
And how do I block access to these ports?
You can find more details about these services in SpeedGuide's Port Database or the IANA Service Port Registry:


ndl-aas/3128
dec_dlm/625


AFAIK neither port is used by OS X out of the box, so you probably have installed some additional stuff on your own (3128 is also used by squid for instance).

To check for processes actively listening on these ports, you can use lsof -i :3128 and lsof -i :625.