{"id":12509,"date":"2024-12-26T13:11:20","date_gmt":"2024-12-26T13:11:20","guid":{"rendered":"https:\/\/ividentia.com\/scenario-vpn-with-easy-to-use-firewall\/"},"modified":"2026-09-14T14:39:11","modified_gmt":"2026-09-14T14:39:11","slug":"scenario-vpn-with-easy-to-use-firewall","status":"publish","type":"post","link":"https:\/\/ividentia.com\/pt-br\/scenario-vpn-with-easy-to-use-firewall\/","title":{"rendered":"Scenario: VPN with Easy-to-Use Firewall"},"content":{"rendered":"

Neste cen\u00e1rio, uma grande empresa de seguran\u00e7a pretende estabelecer uma VPN entre uma porta de conex\u00e3o em Lisboa e um sistema central no Porto, com ambas as redes protegidas por um firewall. Situa\u00e7\u00e3o: Suponha que voc\u00ea seja propriet\u00e1rio de uma grande empresa de seguran\u00e7a com sede no Porto e que tenha acabado de abrir uma… <\/p><\/div>\n

Situa\u00e7\u00e3o<\/h2>\n\n

Imagine you own a large insurance company based in Porto and have just opened a new branch in Lisbon. The Lisbon branch needs access to the customer database at the Porto headquarters. You want to ensure that the transferred information is protected, as the database contains confidential information about your clients, such as names, addresses, and phone numbers. You decide to connect both offices via the internet using a Virtual Private Network (VPN). Both offices are protected by a firewall and use Network Address Translation (NAT) to hide unregistered private IP addresses behind a set of registered IP addresses. However, VPN connections have some well-known incompatibilities with NAT. A VPN connection rejects packets sent by a NAT device because NAT alters the IP address in the packet, thus invalidating the packet. However, you can use a VPN connection with NAT if you implement UDP tunneling. <\/p>\n\n

In this scenario, the private IP address of the Lisbon network is placed in a new IP header and is converted when it passes through Firewall C (see the following image). Then, when the packet reaches Firewall D, it converts the destination IP address to the IP address of System E, and thus the packet will be sent to System E. Finally, when the packet arrives at System E, it decomposes the UDP header, leaving the original IPSec packet, which will now go through all the validations and allow a secure VPN connection. <\/p>\n\n

Objectivos<\/h2>\n\n

Neste cen\u00e1rio, uma grande seguradora pretende estabelecer uma VPN entre uma porta de liga\u00e7\u00e3o em Lisboa (Cliente) e um sistema central no Porto (Servidor), sendo que ambas as redes est\u00e3o protegidas por uma firewall.<\/p>\n\n

Os objectivos deste cen\u00e1rio s\u00e3o os seguintes:<\/p>\n\n