D-Link DVX-1000 User Manual page 87

Appendix A - Appendix
Connections to SOCKS, X-Windows, Open-Windows & NFS ports
The ports to SOCKS, X-Windows, Open-Windows and NFS are blocked, by default, so as to protect the system from
protocol and system administration problems.
Telnet/SSH/FTP/HTTP/HTTPS/TFTP Server/Client
The settings related to either of Telnet/SSH/FTP/HTTP/HTTPS/TFTP server/client can be altered as required.
NTP Client
The setting for allowing the packets related to NTP Client can be modified as required. Currently, these packets are
allowed.
Packets having source address as target system's external IP address
For natural reasons, such packets are blocked.
Packets from machine having private class-A/B/C addresses
Packets from either of the private class A, class B, or class C address received on the external interface are blocked.
Since these address can only be assigned to LANs.
Packets having source IP address as loop back address
Packets claiming to have loop back address as the source IP address are blocked.
Malformed broadcast packets
Malformed broadcast packets are blocked. The packets having "0.0.0.0" as the destination address and/or "255.255.255.255"
as the source address are dropped.
Packets having source IP address as multicast IP Addresses
Multicast IP address cannot be put in the source IP address of the packet. Packet found with such IP address is
blocked.
Packets having class E addresses
Class E being a reserved class, as yet, the packets having source/destination IP as Class E address are blocked.
D-Link DVX-1000 User Manual