Intrusion detection system (IDS)

An intrusion detection system (IDS) is a device or software application that monitors network and/or system activities for malicious activities or policy violations and produces reports to a Management Station. Intrusion prevention is the process of performing intrusion detection and attempting to stop detected possible incidents. Intrusion detection and prevention systems (IDPS) are primarily focused on identifying possible incidents, logging information about them, attempting to stop them, and reporting them to security administrators. In addition, organizations use IDPSs for other purposes, such as identifying problems with security policies, documenting existing threats, and deterring individuals from violating security policies.  IDPSs have become a necessary addition to the security infrastructure of nearly every organization

IDPSs typically record information related to observed events, notify security administrators of important observed events, and produce reports.  Many IDPSs can also respond to a detected threat by attempting to prevent it from succeeding. They use several response techniques, which involve the IDPS stopping the attack itself, changing the security environment (e.g., reconfiguring a firewall), or changing the attack’s content.

Intrusion detection is the ability to identify, track, and stop unauthorized or malicious attacks before they can penetrate and damage your network. Intrusion detection capability is only one part of a complete data security model and complements existing components, such as firewalls, encryption mechanisms, strong authentication systems, etc.

Almost all intrusion detection technologies fall into two basic types of intrusion detection - network-based and host-based.

• A network-based intrusion detection system (IDS) monitors traffic flowing through a network, looking for patterns that indicate unauthorized or malicious activity is taking place.
  
• Host-based and network-based intrusion detection systems can prove invaluable in fortifying your defensive posture.

Mobile ad hoc network (MANETs)

A mobile ad hoc network (MANET), is a self-configuring infra structureless network of mobile devices connected by wireless links.

Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. Each must forward traffic unrelated to its own use, and therefore be a router. The primary challenge in building a MANET is equipping each device to continuously maintain the information required to properly route traffic. Such networks may operate by themselves or may be connected to the larger Internet.

MANETs are a kind of wireless ad hoc networks that usually has a routeable networking environment on top of a Link Layer ad hoc network.

The growth of laptops and 802.11/Wi-Fi wireless networking have made MANETs a popular research topic since the mid 1990s. Many academic papers evaluate protocols and their abilities, assuming varying degrees of mobility within a bounded space, usually with all nodes within a few hops of each other. Different protocols are then evaluated based on measure such as the packet drop rate, the overhead introduced by the routing protocol, end-to-end packet delays, network throughput etc.

virtual private network (VPN)

What is a virtual private network (VPN)?

A virtual private network (VPN) is a network that uses a public telecommunication infrastructure, such as the Internet, to provide remote offices or individual users with secure access to their organization's network. A virtual private network can be contrasted with an expensive system of owned or leased lines that can only be used by one organization. The goal of a VPN is to provide the organization with the same capabilities, but at a much lower cost.

A VPN works by using the shared public infrastructure while maintaining privacy through security procedures and tunneling protocols such as the Layer Two Tunneling Protocol (L2TP). In effect, the protocols, by encrypting data at the sending end and decrypting it at the receiving end, send the data through a "tunnel" that cannot be "entered" by data that is not properly encrypted. An additional level of security involves encrypting not only the data, but also the originating and receiving network addresses.

Secure VPNs use cryptographic tunneling protocols to provide confidentiality by blocking intercepts and packet sniffing, allowing sender authentication to block identity spoofing, and provide message integrity by preventing message alteration.


Secure VPN protocols include the following:

IPsec (Internet Protocol Security) was originally developed for IPv6, which requires it. This standards-based security protocol is also widely used with IPv4. Layer 2 Tunneling Protocol frequently runs over IPsec.

Transport Layer Security (SSL/TLS) can tunnel an entire network's traffic, as it does in the OpenVPN project, or secure an individual connection. A number of vendors provide remote access VPN capabilities through SSL. An SSL VPN can connect from locations where IPsec runs into trouble with Network Address Translation and firewall rules.

Datagram Transport Layer Security (DTLS), is used in Cisco's next-generation VPN product, Cisco AnyConnect VPN, to solve the issues SSL/TLS has with tunneling over TCP.

Microsoft Point-to-Point Encryption (MPPE) works with their Point-to-Point Tunneling Protocol and in several compatible implementations on other platforms.

Microsoft introduced Secure Socket Tunneling Protocol (SSTP) in Windows Server 2008 and Windows Vista Service Pack 1. SSTP tunnels Point-to-Point Protocol (PPP) or Layer 2 Tunneling Protocol traffic through an SSL 3.0 channel.

MPVPN (Multi Path Virtual Private Network). Ragula Systems Development Company owns the registered trademark "MPVPN".^[2]

Secure Shell (SSH) VPN -- OpenSSH offers VPN tunneling to secure remote connections to a network or inter-network links. This should not be confused with port forwarding. OpenSSH server provides limited number of concurrent tunnels and the VPN feature itself does not support personal authentication.