How do I configure access lists to protect my network?
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User’s Guide: Version 1.2
How do I configure access lists to protect my network?
Access Lists provide a filtering mechanism that allows you to limit the
types of traffic you want the V!CAS to route. For example, you might
want to control access to the telnet service on a specific host to one or two
remote ISDN hosts. This is done using Allow and Deny lists.
Below is a brief example of how the Allow and Deny Lists are used.
Before you begin
First decide what types of IP traffic you want to limit. You’ll want to take
the following things into consideration.
• What interface do you want to monitor incoming traffic on.
• What services and/or hosts do you want to allow/deny access to.
• What services do you absolutely need (DNS, FTP, HTTP).
Configure it
Configure Allow Entries
First, configure the Allow entries for the interface you want to moni-
tor IP traffic on. The Source/Destination Address/Mask/Port fields
should be set appropriately depending on what you are filtering.
Mode
allow
Source Interface/Partner
<name of interface to monitor>
➊
Allow Entries
➋
Deny Entries
rsh
pop
nntp
rsh
http
nntp
nntp
udp
pop
ftp
ftp
pop
(any TCP)
(any ftp, telnet, rsh)
http
ftp
egp
telnet
ISDN
anyhost
dialup1
http
Src Port Dest Port
21
<abc>
Src Port Dest Port
23
<def>
Src Port Dest Port
514
<efg>
Secure LAN
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(p. 63)
IP
A
CCESS
L
ISTS
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