What are the types of NAT configured on the firewall?

Abbreviation: Abbreviation.

Full name in English. Explained in Chinese.

natnetwork address translator

Network Address Translation.

Application-layer gateways.

aclaccess control list

Access Control Lists.

vpnvirtual private network

Virtual Private Network.

patport address translation

Port address translation.

no-pat

no-port address translation

The port address is not translated.

1. Brief introduction of features.

1) NAT (Network Address Translation) is the process of converting an IP address in an IP datagram header into another IP address.

2) In practical application, NAT is mainly used to implement the function of private network access to external networks. The use of a small number of public IP addresses as a representation of the majority of private IP addresses will help slow down the depletion of available IP address space; At the same time, it provides a kind of "privacy" protection for the internal network, and can also provide certain services to the external network according to the needs of users.

3) SecPath high-end firewall is based on multi-core CPU processor, which has rich business processing power and high performance, and can be used as a security gateway for large enterprise networks. Available in one-to-many, one-pair.

1. Address translation functions such as internal servers, and support VPN multi-instance at the same time.

79 Explain the NAT configuration of the firewall in detail.

The firewall on the computer is designed to block the intrusion of those systems and the hack to prevent the intrusion of viruses, so as to protect your computer security and protect your privacy and security.

Generally, the router is connected first, and then the firewall. But if your firewall has a routing function and your network architecture is not very complicated, you can use a firewall directly, instead of a router.

The first is that whether or not to do NAT has nothing to do with the port (I mean enterprise-grade routers, such as Cisco, not home devices) but rather depends on the purpose.

2.In the case of Internet access and sharing router port to access the Internet, NAT needs to be used, for example, port E1 is connected to the Internet, and other computers need to use it to access the Internet, then NAT is required in this case

3.If you are connected to a branch switch in a local area, you do not need to enable NAT if it is only used for routing, for example, port E2 is connected to a child switch.

Because of the problem of IPv4 address exhaustion, many networks use private IP addresses internally, and when you need to connect to a public IP address when using a private IP address, you need to do a NAT, because the private IP address is not unique to the public IP address, so you need to convert it to a public IP address through NAT to connect to other public IP addresses.

However, since the connection between the private IP address and the private IP address is unique, NAT address translation is not required.

It's a three-tier network relationship

79 Explain the NAT configuration of the firewall in detail.

Although NAT firewalls and SPI firewalls are firewalls, they are implemented in different ways. NAT firewall is a commonly used network security tool, which establishes a private network, and computers in the network can actively establish connections with the external network, send and receive data, but the connection from the external network is usually blocked. NAT Firewall improves security by hiding computers on the intranet and protecting them from intrusion and unauthorized access from the extranet.

SPI firewall is a technology that inspects packets from the external network before they enter the internal network. It rejects all requests from the public network by default, and dynamically maintains the state of all communications (connections) through the firewall for connections sent from private network requests, and only data packets that respond to internal network requests and meet security requirements can enter the internal network through the firewall. Compared with NAT firewalls, SPI firewalls are more secure.