Cisco ASA 5506-X Configuration Guide

CHAPTER
9-1
Cisco ASA Series Firewall CLI Configuration Guide
9
Network Address Translation (NAT)
The following topics explain Network Address Translation (NAT) and how to configure it.
• Why Use NAT?, page 9-1
• NAT Basics, page 9-2
• Guidelines for NAT, page 9-6
• Dynamic NAT, page 9-12
• Dynamic PAT, page 9-18
• Static NAT, page 9-27
• Identity NAT, page 9-37
• Monitoring NAT, page 9-40
• History for NAT, page 9-41
Why Use NAT?
Each computer and device within an IP network is assigned a unique IP address that identifies the host.
Because of a shortage of public IPv4 addresses, most of these IP addresses are private, not routable
anywhere outside of the private company network. RFC 1918 defines the private IP addresses you can
use internally that should not be advertised:
• 10.0.0.0 through 10.255.255.255
• 172.16.0.0 through 172.31.255.255
• 192.168.0.0 through 192.168.255.255
One of the main functions of NAT is to enable private IP networks to connect to the Internet. NAT
replaces a private IP address with a public IP address, translating the private addresses in the internal
private network into legal, routable addresses that can be used on the public Internet. In this way, NAT
conserves public addresses because it can be configured to advertise at a minimum only one public
address for the entire network to the outside world.
Other functions of NAT include:
• Security—Keeping internal IP addresses hidden discourages direct attacks.
• IP routing solutions—Overlapping IP addresses are not a problem when you use NAT.

Cisco ASA 5506-X Specifications

General

Model	ASA 5506-X
Firewall Throughput	750 Mbps
Maximum Firewall Connections	50, 000
Maximum VPN Peers	50
Integrated Ports	8 x 1 GE
Stateful Inspection Throughput	750 Mbps
Weight	4.4 lb (2 kg)
Firewall Throughput (Multiprotocol)	750 Mbps
Firewall Throughput (Application Visibility and Control AVC)	250 Mbps
Concurrent Sessions	50, 000
New Connections per Second	10, 000
IPsec VPN Throughput	100 Mbps
Interfaces	8 x 1 GE
Memory	4 GB
Flash Memory	8 GB
Form Factor	Desktop
VPN Throughput	100 Mbps
Maximum Concurrent Sessions	50, 000
New Sessions per Second	10, 000
Operating Temperature	32 to 104°F (0 to 40°C)
Storage Temperature	-13 to 158°F (-25 to 70°C)
Power Supply	External
Humidity	10% to 90% non-condensing