Packet Filtering
Issue 4 May 2005 185
What can be filtered
Tab le 10 lists the specific types of traffic that can be filtered.
Packet Filtering and NAT
Network address translation (NAT) and packet filtering services can be run simultaneously.
Depending on the direction of the traffic, the VSU automatically determin es which sequence t he
services will run.
For inbound packets (to the WAN), NAT is run fi rst, then fi ltering. For outbound p ackets, filter ing
is run first, followed by NAT.
Table 10: Traffic types that can be filtered
User-defined TCP Exec Netware-IP/TCP VPN-AuthGW
User-defined IP Finger Netware-IP/UDP VPN-KeepAlive
User-defined UDP FTP Nettimep VPtunnel
AURP FTP/data NFS Who
Bootpc Gopher NFS/TCP WWW-HTTP
Bootps Gopher/UDP NNTP WWW-HTTP/UDP
Bordergw ICMP NNTP/UDP XDMCP
Chargen IDIRACCP NWIP-DSS/TCP
Chargen/UDP IPX/TCP NWIP-DSS/UDP
CMD IPX/UDP Printer
Discard IPrelay Relaychat
Domain IPtunnel SMTP
Domain/TCP Kerberos SNM P
Discard/UDP Login SNMP-Trap
Dynamic/TCP Nameserver Telnet
Dynamic/UDP Nameserver/TCP TFTP
Echo NetBIOS/TCP UUCP
Echo/UDP NetBIOS/UDP UUCP-Path