What port is DHCP DLink running on?

Question

Computer networks

I decided to close all system and vulnerable ports on all interfaces at the router level. But I ran into the problem of autoconfiguring client equipment connected via WI-FI.
Empirically found out that DHCP works on the range of ports 54-79. Tell me, please, which one?
Thank you.

Answer 1

67/68 DHCP port. https://ru.wikipedia.org/wiki/DHCP
But why do you need it. You are expecting a vulnerability from an internal network (LAN) or from the Internet (WAN).
1) if from LAN, then it is enough to enable port isolation. Read more in the manual for the router.
2) if from the WAN, then you do not forget that you are sitting behind NAT, which means that you cannot access the computer through the router. And in order to get it, you need to use, for example, DMZ ( https://ru.wikipedia.org/wiki/DMZ_(%D0%BA%D0%BE%D0...) to do port forwarding from the external interface to the internal one or create forwarding rules. Any attempts to access your IP will be closed on the router, and since the setting is most likely not enabled from the WAN, there will simply be nothing.
I hope it dispelled your doubts about security. And watch less films :) Everything is written in books according to the protocol.

Answer 2

Are you kidding ?
If the wiki is few where everything is written, then keep it https://tools.ietf.org/html/rfc2131

DHCP uses UDP as its transport protocol. DHCP messages from a client
to a server are sent to the 'DHCP server' port (67), and DHCP
messages from a server to a client are sent to the 'DHCP client' port
(68). A server with multiple network addresses (eg, a multi-homed
host) MAY use any of its network addresses in outgoing DHCP messages