Mobile SCTP (mSCTP) is an extension of the Stream Control Transmission Protocol (SCTP). Its primary goal is to support mobility in IP networks, making it particularly beneficial for mobile devices that move across different networks or change their point of attachment to the Internet. While SCTP was primarily designed to transport PSTN (Public Switched Telephone Network) signals over IP networks, mSCTP extends this to better handle mobile IP scenarios.

Here are the main features and characteristics of mSCTP:

  1. Multi-homing Support: One of the primary features of SCTP is its support for multi-homing, which means it can operate over multiple IP addresses. mSCTP leverages this feature to support mobility. When a device with an active mSCTP session moves to a new network, it can add a new IP address (from the new network) to the existing session without disrupting the session.
  2. Seamless Handover: With mSCTP, devices can transition between networks seamlessly. This is crucial for applications that require a continuous connection, such as VoIP calls or live video streaming.
  3. Reduced Handover Latency: Compared to other mobility protocols, mSCTP can offer reduced handover latency. The existing connection is maintained while a new IP address from the new network is added, ensuring a smooth transition.
  4. Connection Preservation: mSCTP ensures that ongoing sessions are not disrupted even if the primary IP address changes due to mobility. This continuity is vital for real-time applications.
  5. Enhanced Security: mSCTP can work in tandem with IPsec to ensure security during handovers between different networks.
  6. Path Switching: If one path (IP address) becomes congested or fails, mSCTP can switch to another available path, enhancing reliability and performance.
  7. Dynamic Address Configuration: mSCTP supports the dynamic addition and deletion of IP addresses during an active session. This is especially important for mobile nodes that may frequently change their point of attachment.

In summary, mSCTP builds upon the robust features of SCTP by adding enhanced mobility support. It addresses the challenges of mobile IP communication, such as handover latency and session disruption, making it a suitable choice for real-time applications on mobile devices.