User Manual

Command Reference Security Commands
12-173
UDP
Allows or denies User Datagram Protocol (UDP) based packets which match
criteria specified by subsequent parameters. Applications that use UDP
include DNS (Domain Name Service), TFTP (a variant of FTP), and BOOTP
(used by some computer systems to acquire IP addresses).
DPort
Defines the destination protocol port. Data packets are filtered based on both
the protocol and on the protocol port of the data packet.
SPort
Defines the source protocol port. Data packets are filtered based on both the
protocol and the protocol port of the data packet.
portNum
A TCP or UDP port number.
portKeyword
A keyword corresponding to the TCP or UDP port number. Available
keywords are BOOTP, DNS, FINGER, FTP, FTPDATA, HTTP, NNTP, NTP,
POP2, POP3, RIP, SMTP, SNMP, SYSLOG, TELNET, and TFTP.
ACK
Allows or denies TCP-based packets in which the ACK (acknowledge) bit is
set.
Examples
Local>> DEFINE FILTER abc ADD DENY IP
(Adds a rule for all IP traffic to filter abc.)
Local>> DEFINE FILTER abc ADD ALLOW IP IPGENERIC OFFSET 0 MASK
0xff000000 LT 0x34000000 TCP DPORT EQ TELNET
(Adds a rule containing an IP generic segment and DPORT to filter abc.)
Local>> DEFINE FILTER abc ADD ALLOW IP SRC 255.255.255.0 192.34.87.0
TCP DSOCK EQ NCP
(Adds a rule containing IP SPORT and SRC to filter abc.)
See Also Define Site Filter, page 12-140; Clear/Purge IP Security, page 12-17; Define
Ports Dialback, page 12-62; Packet Filters and Firewalls, page 11-22