SonicWALL NAT Traversal Support

VPN NAT Traversal is an Internet Draft proposed to IETF (Internet Engineering Task Force) to overcome problems faced when IPSec traffic is intended to pass through a NAT device. NAT Traversal addresses the issue of UDP (User Datagram Protocol) encapsulation by wrapping an IPSec packet inside a UDP packet when a NAT or NAPT (Network Address Port Translator) device is detected between peers.

Encapsulation of the IPSec packet requires decapsulation of the IPSec packet. Since ESP-protected packets are exchanged between IKE peers using one of three methods, gateway to gateway, client to gateway, and client to client, the IKE peers must support the same method of UDP encapsulation. IKE peers exchange a known value to determine if they both support NAT Traversal. If the IKE peers agree, IKE probes or discovery payloads are used to determine if a NAT or NAPT device is present. Only if a NAT or NAPT device is detected is UDP encapsulation is used for IPSec packets.

NAT/NAT Traversal devices use dynamic mappings where a private IP address and source port (192.168.168.168:X) are temporarily bound to a shared public IP address and an unused port

(207.126.101.100:Y). This binding is dissolved after a period of inactivity (minutes or seconds), enabling pool reuse.

IPSec VPNs protect traffic exchanged between authenticated endpoints, but authenticated endpoints cannot be dynamically re-mapped mid-session for NAT traversal to work. Therefore, to preserve a dynamic NAT binding for the life of an IPSec session, a 1-byte UDP is designated as a “NAT Traversal keepalive” and acts as a “heartbeat” sent by the VPN device behind the NAT or NAPT device. The “keepalive” is silently discarded by the IPSec peer.

Selecting Enable NAT Traversal in the Global VPN Settings section of the Summary tab allows VPN tunnels to support this protocol, and log messages are generated by the SonicWALL when a IPSec Security Gateway is detected behind a NAT/NAPT device. The following log messages are found on the View Log tab:

•Peer IPSec Gateway behind a NAT/NAPT device

•Local IPSec Security Gateway behind a NAT/NAPT device

•No NAT/NAPT device detected between IPSec Security

•Peer IPSec Security Gateway doesn’t support VPN NAT Traversal

AES (Advanced Encryption Standard) Support

AES is an encryption algorithm for securings sensitive but unclassified material by U.S. Government agencies. It may become the official encryption standard for commercial transactions in the private sector. As a symmetric algorithm (same key for encryption and decryption), it uses block encryption of 128 bits in size, supporting key sizes of 128, 192, and 256.

AES support is only available on the PRO 230, PRO 330, and GX series. Support is limited to 128 and 256 bit keys for IKE Phase One tunnels, and 128 bit keys for Phase Two tunnels for both IKE and Manual key.

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Internet Security Appliances specifications

SonicWALL Internet Security Appliances are pivotal solutions aimed at safeguarding networks from an ever-evolving array of cyber threats. Designed for small to medium-sized businesses, as well as enterprises, these appliances deliver robust security and high-performance capabilities.

One of the main features of SonicWALL Internet Security Appliances is their Unified Threat Management (UTM) functionality. This integrated approach allows organizations to manage multiple security measures, including firewall protection, intrusion prevention systems (IPS), and antivirus capabilities, within a single device. This consolidation simplifies security management and reduces the risk of vulnerabilities from disparate systems.

Another significant technology found in these appliances is Application Control. This feature enables administrators to monitor and regulate the applications and services used within their networks, ensuring that bandwidth is allocated efficiently, and potentially harmful applications are blocked. Coupled with Content Filtering, SonicWALL offers granular policies to restrict access to inappropriate or non-work-related content, enhancing overall productivity while maintaining security.

SonicWALL appliances also utilize advanced cybersecurity technologies like SonicWall Capture Threat Assessment and Capture Advanced Threat Protection. These solutions leverage artificial intelligence to identify and remove sophisticated malware and ransomware threats before they infiltrate the network. This proactive approach ensures that only safe email and web traffic is allowed through, providing comprehensive protection against advanced persistent threats.

Moreover, SonicWALL’s Global Management System (GMS) enables centralized control over multiple security devices, making it easy for IT teams to maintain a consistent security posture across various locations. This capability is especially beneficial for organizations with distributed networks, as it provides real-time visibility into network activity and security incidents.

The appliances are also designed with scalability in mind. Whether an organization grows or needs to adjust its security policies, SonicWALL appliances can be updated, expanded, or modified without significant disruptions. This flexibility makes them a long-term investment for any business focused on network security.

In addition, SonicWALL's user-friendly interface simplifies the deployment and management processes. With intuitive dashboards and reporting tools, administrators can easily track security events, analyze network traffic patterns, and respond swiftly to potential threats.

In summary, SonicWALL Internet Security Appliances combine essential features like Unified Threat Management, Application Control, and advanced threat protection technologies into a cohesive security solution. Their scalability, centralized management capabilities, and user-friendly interfaces make them an excellent choice for businesses aiming to strengthen their cyber defenses in a complex digital landscape.
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