Why are these ports open in iptables on new FC4 install?

[John DeDourek]

Scot L. Harris wrote:

> <>Finally upgraded my main system to FC4. This was a clean install from
> CD. yum update completed over night. I noticed the following entries
> in the iptables rules:
>
> [...clip...]


> <>-A RH-Firewall-1-INPUT -p 50 -j ACCEPT
> -A RH-Firewall-1-INPUT -p 51 -j ACCEPT

[...clip...]

> <>Looked through the release notes and did not see anything related to
> ports 5353, 50, 51, or 631.
>
For the 50 and 51, that's not port 50 and 51 but protocol 50 and 51.

From
http://www.iana.org/assignments/protocol-numbers
50 is  encapsulating security payload
51 is authentication header

As mentioned previously, this is for "IPSec", i.e. IP Security, 
typically used
for Virtual Private Networks.