Step1: Configure the internal interface vlanĪSA5505(config-if)# ip address 192.168.1.1 255.255.255.0ĪSA5505(config-if)# no shut Step 2: Configure the external interface vlan (connected to Internet)ĪSA5505(config-if)# ip address 200.200.200.1 255.255.255.0ĪSA5505(config-if)# no shut Step 3: Assign Ethernet 0/0 to Vlan 2ĪSA5505(config-if)# switchport access vlan 2ĪSA5505(config-if)# no shut Step 4: Enable the rest interfaces with no shut Let’s now have a look at the Cisco ASA 5505 configuration, in a step by step fashion. Let’s see the basic configuration setup of the most important steps that you need to configure. By default, interface Ethernet0/0 is assigned to VLAN 2 and it’s the outside interface (the one which connects to the Internet), and the other 7 interfaces (Ethernet0/1 to 0/7) are assigned by default to VLAN 1 and are used for connecting to the internal network. That is, you can not configure the physical ports as Layer 3 ports, rather you have to create interface VLANs and assign the Layer 2 interfaces in each VLAN.

The difference of the 5505 model from the bigger ASA models is that it has an 8-port 10/100 switch which acts as Layer 2 only. We will use Port Address Translation (PAT) to translate our internal IP addresses to the public address of the outside interface. We assume that our ISP has assigned us a static public IP address (e.g 200.200.200.1 as an example) and that our internal network range is 192.168.1.0/24. Moreover, the performance of the ASA 5505 appliance supports 150Mbps firewall throughput and 4000 firewall connections per second, which is more than enough for small networks. In this article, I will explain the basic Cisco ASA 5505 configuration for connecting a small network to the Internet (here the complete guides). The Adaptive Security technology of the ASA firewalls offers solid and reliable firewall protection, advanced application-aware security, denial of service attack protection and much more. Although this model is suitable for small businesses, branch offices or even home use, its firewall security capabilities are the same as the biggest models (5510, 5520, 5540 etc). The Cisco ASA 5505 Firewall is the smallest model in the new 5500 Cisco series of hardware appliances.

Cisco asa firewall