User`s guide

Defining Filters and Firewalls
Overview of Filter profiles
Pipeline User’s Guide Preliminary January 30, 1998 6-11
If a filter is applied as a data filter, the “forward” action determines which
packets will be transmitted and received. If a filter is applied as a call filter,
the “forward” action determines which packets can either initiate a
connection or reset the timer for an established connection.
5
Set the source and destination address and mask/
The source and destination Mask and Adrs parameters specify the contents
of the source or destination fields in a packet. Use the Mask parameter to
mask out portions of the source or destination address, for example, to mask
out the host number.
6
Specify the Protocol.
The Protocol parameter is used to identify a specific TCP/IP protocol; for
example, 6 specifies TCP packets. Common protocols are listed below, but
protocol numbers are not limited to this list. For a complete list, see the
section on Well-Known Port Numbers in RFC 1700, Assigned Numbers, by
Reynolds, J. and Postel, J., October 1994.
–1 — ICMP
–5 — STREAM
–8 — EGP
–6 — TCP
– 9 — Any private interior gateway protocol, such as Cisco’s IGRP
– 11 — Network Voice Protocol
– 17 — UDP
– 20 — Host Monitoring Protocol
– 22 — XNS IDP
– 27 — Reliable Data Protocol
– 28 — Internet Reliable Transport Protocol
– 29 — ISO Transport Protocol Class 4
– 30 — Bulk Data Transfer Protocol
– 61 — Any Host Internal Protocol
–89 — OSPF
7
Set the source and destination ports and comparison method.