IPsec (Internet Protocol Security)

IPsec (Internet Protocol Security) is a suite of protocols that provides authentication, integrity and optional encryption for traffic at the IP layer. Because it works below TCP और UDP, applications benefit without any changes.

Why it matters

IPsec is a standard foundation for VPN links between offices and cloud networks, supported by nearly all routers and firewalls. Two parts do the work: IKE (Internet Key Exchange, UDP 500, or 4500 with NAT traversal) authenticates the peers and negotiates keys, and ESP (Encapsulating Security Payload) protects the data. It has two modes: tunnel mode wraps the whole original packet, used for site-to-site VPNs, and transport mode protects only the payload between two hosts.

Configurations have many options, so both ends must agree on algorithms, lifetimes and which traffic is protected.

Example

A typical policy: encrypt traffic between 10.1.0.0/16 and 10.2.0.0/16 using IKEv2, AES-256-GCM and a certificate or pre-shared key. A mismatch in the selected proposal is a frequent cause of a tunnel that never comes up.

Common mistakes

• Using weak pre-shared keys or outdated algorithms.
• Mismatched traffic selectors, so only some subnets pass.
• Overlooking NAT in the path and not enabling NAT traversal.

Related

• VPN
• Tunneling
• WireGuard
• Encryption

यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.