Cisco ASA Firewall Training
1. Cisco ASA Firewall Basic Configuration
Adaptive Security Appliance (ASA) is a Cisco security appliance that combines classic firewall features with VPN, Intrusion Prevention, and antivirus capabilities. It has the capability to provide threat defense before the attacks spread into the networks.Here we are gpoing to configure firewall to have three zone; INSIDE where our internal networks are(trusted zone), DMZ where our servers are located(partially trusted), and finally OUTSIDE where it connects to ISP(untrusted).
Under basic configurations, the following is addressed;
1. Configuring Cisco ASA hostname, enable passwords, username and password.
2. Configuring Cisco ASA system clock and date.
3. Assign an IP address to the interface of ASA.
4. Assign a nameif and security level to the interface of ASA.
5. Save and display configuration in ASA.
To understand how to do Cisco ASA basic configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.
2. Cisco ASA Firewall DHCP Server Configuration
After deviding the firewall into three zones(INSIDE,DMZ,OUTSIDE), we assume that we have control of only INSIDE/DMZ IP device allocation. Thus for DMZ, we do static IP addressing while INSIDE zone we do DHCP allocation and the firewall will be the server.The ASA firewall will provide internet access to all the LANs. Also, the ASA will act as DHCP server for the internal LAN, assigning the required IP addresses for that LAN subnet using a DHCP scope set.
Under DHCP configurations, the following is addressed;
1. (Optional) Configuring Cisco ASA hostname, enable passwords, username and password.
2. Assign an IP address to the interface of ASA.
3. Assign a nameif and security level to the interface of ASA.
4. Configure address range to be used.
5. Configure DNS Server and enable DHCP server on the inside interface.
6. Enable DHCP option on the computers.
To understand how to do Cisco ASA DHCP server configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.
3. Cisco ASA Firewall SSH Configuration
The Cisco ASA firewall appliance provides both graphical and command line methods for connecting to the device for management. With the graphical method, the administrator can use a web browser (https) for managing the firewall. This method necessitates that the ASDM software (Adaptive Security Device Manager) is installed on the flash memory of the firewall.The command line methods use either Telnet or SSH to connect to the device. Since the Telnet protocol sends everything in clear text, it is recommended to use SSH where all communication with the firewall is encrypted.
Under SSH configurations, the following is addressed;
1. Configuring Cisco ASA hostname, enable passwords, domain-name, username and password.
2. Assign an nameif, security level and IP address to the interface of ASA.
3. Assign hosts IP addresses and ensure they can ping the firewall.
4. Configure LOCAL authentication for SSH.
5. Generate RSA crypto key pair.
6. Define subnets or IPs that are allowed to SSH.
7. (Optional)Specify SSH timeout.
To understand how to Cisco ASA SSH configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.
4. Cisco ASA Firewall OSPF + Default Static Routing Configuration
OSPF is an interior gateway routing protocol that uses link states rather than distance vectors for path selection. OSPF propagates link-state advertisements rather than routing table updates. Because only LSAs are exchanged instead of the entire routing tables, OSPF networks converge more quickly than RIP networks. OSPF uses a link-state algorithm to build and calculate the shortest path to all known destinations.In this setup, we have an INSIDE router, perimeter firewall and OUTSIDE/ISP router, thus we have to implement routing protocols to enable communication. OSPF will be enabled between the firewall and the INSIDE router wihile default routes will be between the firewall and OUTSIDE router.
Under OSPF and Default routes configurations, the following is addressed;
1. (Optional)Configuring Cisco ASA hostname, enable passwords, domain-name, username and password.
2. Assign an nameif, security level and IP address to the interface of ASA.
3. Assign routers IP addresses and ensure they can ping the firewall.
4. Configure OSPF for INSIDE router and the firewall.
5. Configure Default Static Routes for the firewall and the ISP router.
To understand how to Cisco ASA IP Routing configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.
5. Cisco ASA Firewall Basic Inspection Policies Configuration
Traffic inspection also enables the ASA administrator to control traffic based on a number of different parameters that exist within the network, including the information contained within the data portion of the traffic.In this setup, we are going to use ACLs and create rules to allow access to various resources such as ICMP, DHCP, DNS, HTTP as well as Email from any subnet to any subnet in this setup thus we call it basic inspection policy.
Under Inspection Policies configurations, the following is addressed;
1. (Optional)Configuring Cisco ASA hostname, enable passwords, domain-name, username and password.
2. Assign an nameif, security level and IP address to the interface of ASA.
3. Configure routing protocols on the devices.
4. Creat object networks and NAT.
5. Configure policies using ACLs to allow all communication between the zones.
To understand how to Cisco ASA Firewall Inspection Policies configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.
6. Cisco ASA Firewall Advanced Inspection Policies Configuration
Traffic inspection also enables the ASA administrator to control traffic based on a number of different parameters that exist within the network, including the information contained within the data portion of the traffic.In this setup, we are going to use ACLs and create rules to allow access to restricted resources such as ICMP, DHCP, DNS, HTTP as well as Email between limited subnets or IP addresses in this setup thus we call it advanced inspection policy.
Under Inspection Policies configurations, the following is addressed;
1. (Optional)Configuring Cisco ASA hostname, enable passwords, domain-name, username and password.
2. Assign an nameif, security level and IP address to the interface of ASA.
3. Configure routing protocols on the devices.
4. Creat object networks and NAT.
5. Configure policies using ACLs to allow communication or access to certain resources only to limited subnets or IP addresses.
To understand how to Cisco ASA Firewall Inspection Policies configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.
7. Cisco ASA Firewall Site-to-Site IPsec VPN Configuration
An IPSec VPN, or Internet Protocol Security Virtual Private Network, is a secure communication tunnel established between the headquarters (HQ) and branch network of an organization over the internet. This VPN connection encrypts the data transmitted between the two locations, ensuring confidentiality and integrity.In a typical setup, the HQ serves as the central hub, while the branch network acts as a remote site. The IPSec VPN tunnel allows users at the branch office to securely access resources hosted at the HQ network, such as servers, applications, and shared files.
The IPSec VPN employs cryptographic protocols to establish and manage the secure connection. It encapsulates data packets with encryption headers, ensuring that sensitive information remains protected from unauthorized access or interception during transit over the internet.
Overall, the IPSec VPN facilitates seamless and secure communication between the HQ and branch network, enabling remote users to collaborate effectively and access essential resources while maintaining the confidentiality and integrity of data transmissions.
In this setup, we are going to implement IPsec VPN between the HQ and branch firewalls to achieve a secure communication between the two sites.
Under Site-to-Site IPsec VPN configurations, the following is addressed;
1. (Optional)Configuring Cisco ASA hostname, enable passwords, domain-name, username and password.
2. Assign an nameif, security level and IP address to the interface of ASA.
3. Configure routing protocols on the devices.
4. Creat object networks and NAT.
5. Configure inspection policies using ACLs to allow communication between the zones.
6. Configure IPsec VPN parameters on the two firewalls.
To understand how to Cisco ASA Site-to-Site IPsec VPN configurations was implemented in the network topology above, kindly click on the link below to get every concept that is explained in a simpler language and terms.