.. title: TCP Durum Makinesi Etkileşimli Diyagramı
.. bilgi: tcp-durum-makinesi
.. tarih: 27.03.2026 12:00:00 UTC
.. Etiketler: ağ iletişimi, tcp, rfc793, durum makinesi, hesap makinesi, araç
.. kategori: Hesap Makineleri
.. bağlantı:
.. açıklama: Tüm RFC 793 durumlarını kapsayan tıklanabilir TCP durumu makine diyagramı. Tetikleyici olayları, alınıp verilen paketleri, zamanlayıcıları ve sık karşılaşılan takılıp kalma durumları için teşhis ipuçlarını gösterir.
.. yazın: metin
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<h2>TCP Durum Makinesi Etkileşimli Şeması</h2>
<p>Tetikleyici olayları, değiştirilen paketleri, zamanlayıcıları ve takılı durum teşhis ipuçlarını görmek için herhangi bir durum düğümüne tıklayın.</p>
<div class="legend">
<div class="legend-item"><div class="legend-dot" style="background:#28a745"></div>Başlangıç/Bitiş durumları</div>
<div class="legend-item"><div class="legend-dot" style="background:#4CAF50"></div>Normal durumlar</div>
<div class="legend-item"><div class="legend-dot" style="background:#dc3545"></div>TIME_WAIT / takıldı</div>
<div class="legend-item"><div class="legend-dot" style="background:#f7971e"></div>Kapanış durumları</div>
</div>
</div>
<div class="result-section">
<div class="section-header">Durum Diyagramı</div>
<div class="section-content" style="padding:12px">
<div id="cy"></div>
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</div>
<div class="result-section" id="detailPanel">
<div class="section-header">Durum Ayrıntıları</div>
<div class="section-content" id="detailContent">
<p style="color:#999">Ayrıntıları görmek için yukarıdaki bir durum düğümünü tıklayın.</p>
</div>
</div>
</div>
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    LISTEN:     { color:'#0f3460', event:'Server calls listen(). Waiting for SYN.',
        packet:'Receives SYN', timer:'—',
        desc:'Server is waiting for an incoming connection request.',
        diagnosis:'Stuck LISTEN: Port not open. Check: ss -lntp | grep &lt;port&gt;' },
    SYN_SENT:   { color:'#0f3460', event:'Client calls connect(). SYN sent.',
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        packet:'Receives SYN, sends SYN-ACK', timer:'SYN-backlog timer',
        desc:'Server received SYN, replied with SYN-ACK, waiting for ACK (3-way handshake).',
        diagnosis:'Many SYN_RCVD: SYN flood / DDoS. Enable tcp_syncookies: sysctl -w net.ipv4.tcp_syncookies=1' },
    ESTABLISHED:{ color:'#28a745', event:'ACK received. Connection open.',
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        diagnosis:'Stuck FIN_WAIT_2: Remote app never called close(). Reduce tcp_fin_timeout. ss -ant state fin-wait-2' },
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        diagnosis:'Many TIME_WAIT: Normal under high connection rate. Mitigate: tcp_tw_reuse=1, reduce tcp_fin_timeout, use persistent connections, or load balance across more ports.' },
};

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