Table Of Contents
PIX Firewall Network Interface Information
Authentication and Authorization
Firewall Configuration Forms
Installing PIX Firewall requires a thorough knowledge of your company's network topology and security policy. To get the PIX Firewall running immediately, fill in the information in Table A-1 to Table A-4, and proceed to "Basic Firewall Configuration." To configure the PIX Firewall for specific types of network traffic, fill in the information in Table A-5 through Table A-8, and follow the instructions in "Managing Network Access and Use."
Information may not appear in the same order in the forms as it does in command syntax. page within the Cisco PIX Firewall Command Reference provides the complete syntax for all PIX Firewall commands.
This appendix includes the following sections:
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PIX Firewall Network Interface Information
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Authentication and Authorization
For specific information about your network environment, contact your network administrator.
PIX Firewall Network Interface Information
Each PIX Firewall has two or more physical network interfaces. Configure each interface with an IP address, network speed, maximum transmission unit (MTU) size, and so on. Refer to page within the Cisco PIX Firewall Command Reference for complete information on the interface command. Table A-1 provides a form for entering PIX Firewall network interface information.
Table A-1 PIX Firewall Network Interface Information
Interface Name Interface Type Hardware ID InterfaceIP Address Interface Speed MTU Size Interface Security LevelOutside
0
Inside
100
Routing Information
Table A-2 provides a form for entering route information. Refer to the Cisco PIX Firewall Command Reference for complete information on the route command and the rip command. The router IP addresses should not be the same as the PIX Firewall interface IP address, or the same as any global address specified in Table A-3.
Network Address Translation
Table A-3 provides a form for gathering the global address pool information. Table A-4 links internal network addresses with the global pool information. The information in Table A-3 and Table A-4 work together to set up NAT and PAT on the PIX Firewall. Refer to the Cisco PIX Firewall Command Reference for complete information on the global and nat commands.
Table A-3 Outside (Global) Network Address or Address Range
Outside or Perimeter Interface Name NAT ID Number from Table A-3 Beginning of IP Address Range End of IP Address Range (Optional)1 Comments
1 Do not enter an ending IP address for PAT assignments. PAT uses only a single IP address.
Table A-4 maps internal (inside) or perimeter network addresses with global network addresses on other interfaces in the PIX Firewall.
Table A-4 Inside (Local) or Perimeter Network Address Translation
Inside or Perimeter Name from Table A-1 NAT ID Number(1 to 65,000) Network Address Mapped to the NAT ID Network Mask for This Address Comments
Static Address Translation
We recommend completing the information on Table A-1 to Table A-4 and completing the instructions provided in "Basic Firewall Configuration," before attempting advanced configuration. After completing and testing your basic configuration, complete the information in Table A-5, which defines advanced configuration settings for static address mapping. Then refer to "Managing Network Access and Use," for instructions about how to use this information. Refer to the Cisco PIX Firewall Command Reference for complete information on the static command.
Note
Static addresses should not be members of the global address pool specified in Table A-3. If the internal host requires Internet access, the static address should be a NIC-registered address.
Table A-5 Static Address Mapping
Interface on Which theHost Resides Interface Name Where the Global Address Resides Host IP Address Static IP Address Comments
Inbound Access Control
Before attempting advanced configuration, we recommend completing the information on Table A-1 to Table A-4 and completing the instructions provided in "Basic Firewall Configuration." After completing and testing your basic configuration, complete the information in Table A-6, which defines advanced configuration settings for inbound access control. Then refer to "Managing Network Access and Use," for instructions about how to use this information. Refer to the Cisco PIX Firewall Command Reference for complete information on the access-list and access-group commands.
To control access by IP address, configure an access-list command statement. To control access by user, set up authentication, as shown in Table A-8. A global or static address should exist for an internal host or network before you can set up a access-list command statement. See Table A-3 and Table A-5 to configure a global or static entry for an internal host.
Table A-6 Inbound Access Control
Access List Identifier Permit or Deny Network Protocol: UDP, TCP, ICMP, or Number Source Address:
External Host or Network IP Address(es) and Network Mask Destination Address:
Static IP Address and Network Mask from Table A-51 Destination Ports 2 Interface To
Bind List
1 Use the keyword "any" to specify all global IP addresses.
2 To specify a single port or a range of ports, you can use operands: greater than, less than, equal, not equal, and range.
The following is a list of literal port names that you can use when configuring an access-list command statement: DNS, ESP, FTP, H323, HTTP, IDENT, NNTP, NTP, POP2, POP3, PPTP, RPC, SMTP, SNMP, SNMPTRAP, SQLNET, TCP, Telnet, TFTP, and UDP. You can also specify these ports by number. Port numbers are defined in RFC 1700.
You should have two access-list command statement definitions to permit access to the following ports:
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DNS, Discard, Echo, Ident, NTP, RPC, SUNRPC, and Talk each require one definition for TCP and one for UDP.
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PPTP requires one definition for port 1723 on TCP and another for port 0 and GRE.
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TACACS+ requires one definition for port 65 on TCP and another for port 49 on UDP.
Outbound Access Control
Before performing advanced configuration, we recommend completing the information on Table A-1 to Table A-4 and completing the instructions provided in "Basic Firewall Configuration." After completing and testing your basic configuration, complete the information in Table A-6, which defines advanced configuration settings for inbound access control. Then refer to "Managing Network Access and Use," for instructions about how to use this information. Refer to the Cisco PIX Firewall Command Reference for complete information on the access-list and access-group commands. To configure access control by IP address, complete the form provided in Table A-7. To control access by user, set up authentication, as defined in Table A-8.
Table A-7 Outbound Access Control
Access List Identifier Permit or Deny Network Protocol: UDP, TCP, or Number Source Address:
External Host or Network IP Address(es) and Network Mask Destination Address or Network IP and Network Mask from Table A-51 Destination Ports (Services) 2 Interface To
Bind Access List To
1 Use the keyword "any" to specify all global IP addresses.
2 To specify a single port or a range of ports, you can use operands: greater than, less than, equal, not equal, and range.
You can also specify a port with the source address, but this is seldom used.
Precede host addresses with the host parameter.
Use the interface name with the access-group command.
Refer to "TCP/IP Reference Information," for a list of protocol values. In addition, you can specify protocols by number.
Authentication and Authorization
Before performing the advanced configuration defined in Table A-8, we recommend completing the information on Table A-1 to Table A-4 and completing the instructions provided in "Basic Firewall Configuration." After completing and testing your basic configuration, complete the information in Table A-7, which defines advanced configuration settings for inbound access control. Then refer to "Managing Network Access and Use," for instructions about how to use this information. Refer to the Cisco PIX Firewall Command Reference for complete information on the aaa command.
Table A-8 defines the information needed applications that provide user authentication and authorization for network connections. Authentication servers include TACACS+ and RADIUS.
Note
If your configuration requires a host on an outside (lower security level) interface to initiate connections with a host on a local (higher security level) interface, create static and access-list command statements for that connection as defined in Table A-5 and Table A-6.
Prior to defining authentication and authorization requirements, identify the authentication server you are using, along with the IP address of the server, and the server encryption key on the PIX Firewall. Enter the information in the following form:
Authentication server (TACACS+ or RADIUS):_________________________
IP address: _________________________ Encryption key:_________________________
If you have additional authentication servers, list them separately.
Table A-8 Authentication and Authorization
Select Authentication or Authorization Interface Name On Which to Authenticate or Authorize Connections Protocol That Will Be Used to Provide Authentication: ANY, FTP, HTTP, TELNET Authentication Server Type: TACACS+
or RADIUS Local Host or Network IP Address1 and Network Mask Foreign Host or Network IP Address2 and Network Mask
1 For a local interface, this is the internal host or network address from which connections originate. For an outside interface, this is the internal host or network address to which connections are sought.
2 For a local interface, this is the internal host or network address to which connections are sought. For an outside interface, this is the external host or network address from which connections originate.
