Graceful Connection Termination
=======================================

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        **What is Graceful Connection Termination?**

        Graceful connection termination is a controlled process in which a connection-oriented protocol like TCP properly closes a session between two devices, ensuring all data is transmitted and acknowledged before disconnection.

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        **Why is Graceful Connection Termination useful?**

        It prevents data loss and ensures that both communicating devices agree to end the session. This clean termination avoids issues like half-open connections or resource leaks.

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        **How does Graceful Connection Termination work?**

        In TCP, the termination process uses a **four-step handshake** involving `FIN` and `ACK` flags. Each side independently closes its sending channel while acknowledging the other’s closure.

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        **Where is Graceful Connection Termination used?**

        It is used in all **TCP-based applications**, such as web browsers, file transfer programs, email clients, and SSH sessions, where clean session closure is necessary.

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        **Which OSI layer does Graceful Connection Termination belong to?**

        Graceful termination is a function of the **Transport Layer (Layer 4)**, managed by TCP as part of its reliable communication model.

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        **Is Graceful Connection Termination Windows specific?**

        No, it is a standard feature of the TCP protocol and works across all platforms including Windows, Linux, and macOS.

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        **Is Graceful Connection Termination Linux specific?**

        No, this mechanism is universally implemented as part of TCP on all modern operating systems and networking devices.

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        **Which Transport Protocol is used by Graceful Connection Termination?**

        **TCP (Transmission Control Protocol)** is the primary transport protocol that supports graceful connection termination.

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        **Is Graceful Connection Termination using client-server model?**

        Yes, graceful termination is commonly seen in client-server communications, where either the client or server initiates a clean connection closure to end the session reliably.


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        Topics in this section,

                * :ref:`Learnings in this section <Graceful_Connection_Termination_step1>`

                * :ref:`Terminology <Graceful_Connection_Termination_step2>`

                * :ref:`Version Info <Graceful_Connection_Termination_step3>`

                * :ref:`Graceful_Connection_Termination Basic Setup on Ubuntu using IPv4 <Graceful_Connection_Termination_step18>`

                * :ref:`TCP Feature : Graceful Connection Termination <Graceful_Connection_Termination_step4>`
                
                * :ref:`Reference links <Graceful_Connection_Termination_step17>`
 
.. _Graceful_Connection_Termination_step1:

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    .. tab-item:: Learnings in this section

        * In this section, you are going to learn

.. _Graceful_Connection_Termination_step2:

.. tab-set::

    .. tab-item:: Terminology
        
       * Terminology


.. _Graceful_Connection_Termination_step3:

.. tab-set::

    .. tab-item:: Version Info 
    
         * Version Info


.. _Graceful_Connection_Termination_step18:

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   .. tab-item:: Graceful_Connection_Termination Basic Setup on Ubuntu using IPv4
       
      * setup

.. _Graceful_Connection_Termination_step4:

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    .. tab-item:: TCP Feature : Graceful Connection Termination

         **Graceful Connection Termination - Testcases**

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.. _Graceful_Connection_Termination_step17:

.. tab-set::

    .. tab-item:: Reference links
     
       * Reference links