Doubt about ADSL security.

[Cassius V. de Magalhaes]

Em Qui, 2004-09-02 às 15:58, cviniciusm escreveu:
> Hello,
> 
> I have a nic card and a ADSL modem. The ADSL modem thas NAT, Firewall,
> IP Filter and DHCP Server. The nic card has a private IP address and
> the modem has a public IP address. All just works fine. The firewall
> has attack protection and DOS protection both active. Need I more
> protection, on Windows 2000 and on Fedora Core 2?
> 
> Thanks in advance, Vinicius.
> 

Following is the iptable's rule configuration:
"# Firewall configuration written by system-config-securitylevel
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:RH-Firewall-1-INPUT - [0:0]
-A INPUT -j RH-Firewall-1-INPUT
-A FORWARD -j RH-Firewall-1-INPUT
-A RH-Firewall-1-INPUT -i lo -j ACCEPT
-A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT
-A RH-Firewall-1-INPUT -p 50 -j ACCEPT
-A RH-Firewall-1-INPUT -p 51 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited
COMMIT"

Is it the RH-Firewall-1-INPUT a chain?
The system-config-securitylevel is so basic, could I change it manually?
Does the above configuration protect me from anything?