In response to large-scale network attacks or information theft, overseas high-defense servers and high-defense IPs will have their own multiple traffic encryption technologies, which encrypt the transport layer, application layer and protocol structure to improve data transmission security. These encryption methods can be lower than DPI, prevent sensitive information from being intercepted/tampered or forged, DNS pollution malicious analysis and other behaviors, improve the stability and concealment of the server's anti-intrusion and anti-attack capabilities, and are the core components of building a highly available and secure network architecture.
First of all, the SSL/TLS encryption protocol is the most basic encryption technology in overseas high-defense environments. TLS (Transport Layer Security Protocol) is widely used in protocols such as HTTPS, SMTP, IMAP, FTP, etc., and can effectively encrypt the communication content between the client and the server, including the request header, request body and response data. Through digital certificate authentication and public-private key mechanisms, the TLS protocol implements confidentiality and integrity protection during session key negotiation, effectively preventing man-in-the-middle attacks and data leakage. In a high-defense IP environment, service providers often deploy hardware-level SSL offload modules to reduce CPU resource consumption caused by encryption processing, while improving the concurrent capacity of encrypted connections.
The second common encryption method is IPSec (Internet Protocol Security), which is an end-to-end encryption mechanism implemented at the network layer. IPSec is usually used in private networks, dedicated line interconnection, and cross-regional IDC data synchronization scenarios. In the IPSec protocol structure, ESP (Encapsulating Security Payload) and AH (Authentication Header) are used to encrypt and verify data packets. IPSec can be deployed on multiple nodes such as hosts, gateways, and firewalls. It has strong compatibility and flexibility and is an important means to build overseas high-security data channels. When configuring IPSec, high-defense service providers often combine IKEv2 dynamic key exchange and two-way authentication strategies to improve security levels and reduce the possibility of attackers obtaining keys.
Third, the QUIC protocol combined with TLS 1.3 encryption is an emerging transport layer encryption solution, which is particularly suitable for CDN, edge acceleration, and high-defense back-to-source scenarios. QUIC is built on UDP and naturally has faster connection establishment and handshake efficiency than TCP. At the same time, it has a built-in complete TLS 1.3 encryption framework, and all communication content is encrypted and authenticated before transmission. Compared with the traditional TLS over TCP architecture, QUIC is more stable in high packet loss and high latency environments, and is particularly suitable for high-hop networks such as Asia to Europe, America, and the Middle East. Most overseas high-defense nodes have begun to introduce QUIC acceleration as the default channel to improve encryption efficiency and throughput.
The fourth category is the application layer encryption mechanism, which usually exists in the form of HTTPS API communication and content encryption transmission. This technology does not rely on the underlying network protocol, but directly encrypts the application data using algorithms such as AES, RSA, or ChaCha20 when it is generated. Even if the network transmission process is completely monitored, the attacker cannot decrypt the content. When connecting to customer business systems, some high-defense platforms provide SDK or middleware interfaces, directly embed data encryption modules, separate the original business logic from the security layer, and ensure that sensitive content remains unreadable when the data link is leaked.
Fifth, tunnel encryption technology (such as GRE over IPSec, SSL private network, and Open private network) also occupies an important position in overseas high-defense deployments. The basic principle is to encapsulate the original traffic in an encrypted channel for transmission. Regardless of whether the source data is plain text or encrypted, its transmission process is always protected. By combining the encapsulation methods of different protocol stacks, this type of technology can be adapted to a variety of business applications, including website access, database connection, remote office, etc. Tunnel encryption is particularly suitable for establishing exclusive encrypted channels under public network IPs, and can be combined with ACL access control lists for refined authorization to improve the communication security level.
Sixth, DNS encryption schemes, such as DoH (DNS over HTTPS) and DoT (DNS over TLS), are used to prevent hijacking and monitoring during domain name resolution. In traditional DNS, query content is transmitted in plain text on UDP port 53, which is easily intercepted or redirected by a third party. DoH encapsulates DNS queries in HTTPS, while DoT directly encrypts them through the TLS port. These two methods have been accepted by multiple international high-defense platforms to enhance the confidentiality of domain name resolution links and prevent attackers from using DNS hijacking to implement malicious guidance or domain name pollution.
Seventh, data fragmentation encryption is also a special high-defense traffic protection strategy. This technology splits a complete data into multiple data packets according to the specified strategy, and encrypts them separately with independent encryption keys. During the transmission process, they reach the target node through different paths. The original content can only be restored after aggregation and decryption at the target end. This method has strong anti-traffic analysis capabilities, which can effectively resist attacks such as side channel analysis and traffic identification, and is adopted in highly sensitive business systems.
In short, overseas high-defense servers and high-defense IPs do not rely solely on hardware packet loss and traffic clarity to improve security protection capabilities, but also use multi-level and multi-structure traffic encryption technology to carry out systematic overall reinforcement. Various encryption protocols and strategies have different roles in different business needs, forming a complete encrypted transmission system from the link layer to the application layer. When selecting an overseas high-defense platform, enterprises should combine their own business types, transmission performance requirements and data compliance standards to clarify the supported encryption methods and their deployment strategies to ensure the overall service is safe, reliable and low-latency.
