topic Re: GlobalProtect: Port 4501 UDP in General Topics

GlobalProtect: Port 4501 UDP

mmclimans — Tue, 16 Feb 2016 16:02:54 GMT

Hi all,

I understand that GlobalProtect uses TCP 443 and UDP 4501... But what is there any more information available about GlobalProtects usage of port 4501? All I could find is the following:

TCP/443 for the SSL communication
UDP/4501 for tunnel communication to the GlobalProtect Gateway

It doesn't really include much about it.. any insight is much appreciated.

Thanks.

Re: GlobalProtect: Port 4501 UDP

Raido_Rattameister — Tue, 16 Feb 2016 16:20:41 GMT

It tries to use UDP 4501.

Client will show protocol as IPSec.

If client is in limited network then GlobalProtect will fall back to TCP 443.

Client will show protocol SSL.

Issue is that in case on SSL TCP packets received from application are encapsulated into second TCP packet.

It adds overhead and can cause problems in case of bad connectivity (Search what "TCP meltdown" means).

Re: GlobalProtect: Port 4501 UDP

Ranga — Wed, 01 Apr 2020 17:56:30 GMT

CMD>netstat -an | findstr 4501

CMD>netstat -an | findstr 443

Re: GlobalProtect: Port 4501 UDP

NazrinShikhaliyeva — Fri, 17 Nov 2023 13:58:33 GMT

Hello,

Here I have a question.

If we restrict access for port 4501, what happens? Does it cause bad connectivity or smth else?

Thanks beforehand.