Network Address Translation (NAT) is a networking process which is used to remap a specific IP address space into another IP address space by modifying the information in the TCP/IP packet header while the packets are being transmitted across a routing device. E.g.(router, firewall etc). Usually the modification is done on the source IP address […]
Access List & NAT on Cisco ASA Firewall-Order of Operation & Examples
Access Control Lists (ACLs) and Network Address Translation (NAT) are two of the most common features that coexist in the configuration of a Cisco ASA appliance. For both inbound and outbound access control lists, the IP addresses specified in the ACL depend on the interface where the ACL is applied. These IP addresses must be […]
Configuring NAT on Cisco IOS Routers
The depletion of the public IPv4 address space has forced the internet community to think about alternative ways of addressing networked hosts. Network Address Translation (NAT) therefore was introduced to overcome these addressing problems that occurred with the rapid expansion of the Internet. Even if NAT was suggested as a temporary solution, it has been […]
Configuring PPPoE for Cisco Router 520 and for series 850 and 870
The Cisco 520 Ethernet to Ethernet router can be used as a PPPoE Client (Point to Point over Ethernet) to connect a small office to a DSL service for Internet access. Also, using Network Address Translation (NAT), you can connect multiple computers to the Internet using the same router. The same configuration applies also for […]
ASA Firewall NAT Control Feature
With the original PIX firewall models, all traffic traversing a Cisco Firewall between inside to outside (higher security level to lower security level) had to match a NAT rule, otherwise the traffic was blocked. For example, in order for an inside web client host to access an outside web server host, there should have been a NAT translation […]