3Com REMOTE ACCESS SYSTEM 1500, Management Manual

Page: 223 / 300

Creating Filters
221
Protocol Sections
A single filter file can contain protocol sections in any order, but sections
cannot be repeated. The following conditions cause errors or prevent
filtering:
■
If you do not specify a protocol section in the filter file, no filtering will
occur and packets of that protocol type will be accepted.
■
If you specify a protocol section but do not define rules, an error will
occur.
■
If you omit a line number or insert a line out of sequence, errors will
occur.
To comment out a protocol section, you must place a pound (#) sign
before the section header and before all rules defined in that section.
Table 57 describes valid protocol sections you can define in the filter file.
Table 57 Valid Protocol Sections
Protocol Rules
You define protocol rules within each protocol section in the filter file.
These rules set which packets may and may not access the network. The
following is the rule syntax:
<line #> <verb> <keyword> <operator> <value>;
The combination of keyword, operator, and value forms a condition
which, when combined with a verb, sets whether packets are accepted or
rejected.
Protocol Description
IP: IP protocol data filter section
IP-CALL: IP protocol call filter section
IP-RIP: IP RIP advertising filter section
IPX: IPX protocol data filter section
IPX-CALL: IPX protocol call filter section
IPX-RIP: IPX RIP advertising filter section
IPX-SAP: IPX SAP advertising filter section
LOGIN-ACCESS: Login Access filter section
ATALK: Appletalk protocol data filter section
ATALK-CALL: Appletalk protocol call filter section
ATALK-RTMP: Appletalk RTMP advertising filter section
ATALK-ZIP: Appletalk ZIP advertising filter section