diff --git a/src/org/class_notes.html b/src/org/class_notes.html
deleted file mode 100644
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-<div id="content" class="content">
-<h1 class="title">Class notes</h1>
-<div id="table-of-contents" role="doc-toc">
-<h2>Table of Contents</h2>
-<div id="text-table-of-contents" role="doc-toc">
-<ul>
-<li><a href="#org740344c">1. class 1 <i>sun sep 17 13:04:43 2023</i></a>
-<ul>
-<li><a href="#orgdeedad1">1.1. Les Reseaux locaux (LAN)</a></li>
-<li><a href="#org4046b4b">1.2. MAC Address :</a></li>
-<li><a href="#orgc7732e1">1.3. RJ-45 connecteurs</a></li>
-<li><a href="#org0f55269">1.4. IPV4 classes :</a></li>
-<li><a href="#org4127e6b">1.5. Adresses privées:</a></li>
-<li><a href="#orge90d8a0">1.6. 500 hosts :</a></li>
-<li><a href="#org67a8bc7">1.7. 150 hosts :</a></li>
-<li><a href="#orgea65848">1.8. 60 hosts :</a></li>
-<li><a href="#org9afb58b">1.9. 30 hosts:</a></li>
-<li><a href="#orge54390c">1.10. 20</a></li>
-<li><a href="#orgd72daa2">1.11. 15</a></li>
-</ul>
-</li>
-<li><a href="#orgc3dfb36">2. Class 2Sun <i>Sep 24 09:09:28 2023</i></a>
-<ul>
-<li><a href="#org7607698">2.1. CCTV (finally)</a></li>
-</ul>
-</li>
-</ul>
-</div>
-</div>
-
-
-<div id="outline-container-org740344c" class="outline-2">
-<h2 id="org740344c"><span class="section-number-2">1.</span> class 1 <i>sun sep 17 13:04:43 2023</i></h2>
-<div class="outline-text-2" id="text-1">
-</div>
-<div id="outline-container-orgdeedad1" class="outline-3">
-<h3 id="orgdeedad1"><span class="section-number-3">1.1.</span> Les Reseaux locaux (LAN)</h3>
-<div class="outline-text-3" id="text-1-1">
-<p>
-Cable 10 mbps ou moins = Ethernet
-Cable 100 mbps = Fast Ethernet
-Cable 1000 mbps ou plus = Giga Ethernet
-</p>
-</div>
-</div>
-
-<div id="outline-container-org4046b4b" class="outline-3">
-<h3 id="org4046b4b"><span class="section-number-3">1.2.</span> MAC Address :</h3>
-<div class="outline-text-3" id="text-1-2">
-<p>
-First three Bytes : vendor
-Last three Bytes : Unique ID
-(In Hexadecimal)
-</p>
-
-<p>
-TODO: CSMA/ CA CD
-</p>
-</div>
-</div>
-
-<div id="outline-container-orgc7732e1" class="outline-3">
-<h3 id="orgc7732e1"><span class="section-number-3">1.3.</span> RJ-45 connecteurs</h3>
-<div class="outline-text-3" id="text-1-3">
-</div>
-<ol class="org-ol">
-<li><a id="org4039adc"></a>Straight<br /></li>
-<li><a id="orgea66000"></a>Crossover (croisé)<br /></li>
-<li><a id="orgfd2e4fe"></a>Rollover (console)<br /></li>
-</ol>
-</div>
-
-<div id="outline-container-org0f55269" class="outline-3">
-<h3 id="org0f55269"><span class="section-number-3">1.4.</span> IPV4 classes :</h3>
-<div class="outline-text-3" id="text-1-4">
-<ul class="org-ul">
-<li>Classe A : 0 - 127  /8
-<ul class="org-ul">
-<li>0.0.0.0/0 : route par default</li>
-<li>127.0.0.0/8 : bouclage</li>
-</ul></li>
-<li>Classe B : 128 - 191  /16
-<ul class="org-ul">
-<li>169.254.0.0/16 : APIPA</li>
-</ul></li>
-<li>Classe C : 192 - 223  /24</li>
-<li>Classe D : 224 - 239
-<ul class="org-ul">
-<li>Multicast</li>
-</ul></li>
-<li>Classe E : 240 - 255</li>
-</ul>
-</div>
-</div>
-
-<div id="outline-container-org4127e6b" class="outline-3">
-<h3 id="org4127e6b"><span class="section-number-3">1.5.</span> Adresses privées:</h3>
-<div class="outline-text-3" id="text-1-5">
-<ul class="org-ul">
-<li>Classe A : 10.0.0.0 - 10.255.255.255 /8</li>
-<li>Classe B : 172.16.0.0 - 172.31.255.255 /12</li>
-<li>Classe C : 192.168.0.0 - 192.168.255.255 /16</li>
-</ul>
-
-
-<p>
-8   7   6   5   4   3   2   1
-128 64  32  16  8   4   2   1
-256 128 64  32  16  8   4   2
-/24 /25 /26 /27 /28 /29 /30 /31
-</p>
-
-<p>
-500
-150
-60
-30
-20
-15
-</p>
-</div>
-</div>
-<div id="outline-container-orge90d8a0" class="outline-3">
-<h3 id="orge90d8a0"><span class="section-number-3">1.6.</span> 500 hosts :</h3>
-<div class="outline-text-3" id="text-1-6">
-<p>
-Addresse: 10.0.0.0 /23
-</p>
-
-<p>
-500 - 256 = 244
-</p>
-
-<p>
-First IP : 10.0.0.1 /23
-Last IP : 10.0.1.254 /23
-@B IP : 10.0.1.255 /23
-Mask : 255.255.254.0
-</p>
-</div>
-</div>
-
-<div id="outline-container-org67a8bc7" class="outline-3">
-<h3 id="org67a8bc7"><span class="section-number-3">1.7.</span> 150 hosts :</h3>
-<div class="outline-text-3" id="text-1-7">
-<p>
-Addresse: 10.0.2.0 /24
-First IP: 10.0.2.1 /24
-Last IP: 10.0.2.254 /24
-@B IP: 10.0.2.255 /24
-Mask: 255.255.255.0
-</p>
-</div>
-</div>
-
-<div id="outline-container-orgea65848" class="outline-3">
-<h3 id="orgea65848"><span class="section-number-3">1.8.</span> 60 hosts :</h3>
-<div class="outline-text-3" id="text-1-8">
-<p>
-Addresse: 10.0.3.0 /26
-First IP: 10.0.3.1 /26
-Last IP: 10.0.3.63 /26
-@B IP: 10.0.3.64 /26
-Mask: 255.255.255.191
-</p>
-</div>
-</div>
-
-<div id="outline-container-org9afb58b" class="outline-3">
-<h3 id="org9afb58b"><span class="section-number-3">1.9.</span> 30 hosts:</h3>
-<div class="outline-text-3" id="text-1-9">
-<p>
-Addresse: 10.0.3.63/8
-First IP: 10.0.3.64/8
-Last IP: 10.0.3.96/8
-@B IP: 10.0.3.97/8
-Mask: 255.255.255.158/11
-</p>
-</div>
-</div>
-
-<div id="outline-container-orge54390c" class="outline-3">
-<h3 id="orge54390c"><span class="section-number-3">1.10.</span> 20</h3>
-<div class="outline-text-3" id="text-1-10">
-<p>
-Addresse: 10.0.3.97/8
-First IP: 10.0.3.98/8
-Last IP: 10.0.3.128/8
-@B IP: 10.0.3.129/8
-Mask: 255.255.255.126/11
-</p>
-</div>
-</div>
-<div id="outline-container-orgd72daa2" class="outline-3">
-<h3 id="orgd72daa2"><span class="section-number-3">1.11.</span> 15</h3>
-<div class="outline-text-3" id="text-1-11">
-<p>
-Addresse: 10.0.3.129/8
-First IP: 10.0.3.130/8
-Last IP: 10.0.3.144/8
-@B IP: 10.0.3.145/8
-Mask: 255.255.255.110/12
-</p>
-</div>
-</div>
-</div>
-
-<div id="outline-container-orgc3dfb36" class="outline-2">
-<h2 id="orgc3dfb36"><span class="section-number-2">2.</span> Class 2Sun <i>Sep 24 09:09:28 2023</i></h2>
-<div class="outline-text-2" id="text-2">
-</div>
-<div id="outline-container-org7607698" class="outline-3">
-<h3 id="org7607698"><span class="section-number-3">2.1.</span> CCTV (finally)</h3>
-</div>
-</div>
-</div>
-<div id="postamble" class="status">
-<p class="author">Author: Crystal</p>
-<p class="date">Created: 2024-04-19 Fri 19:58</p>
-<p class="validation"><a href="https://validator.w3.org/check?uri=referer">Validate</a></p>
-</div>
-</body>
-</html>
diff --git a/src/org/class_notes.org b/src/org/class_notes.org
deleted file mode 100755
index fe1d9a1..0000000
--- a/src/org/class_notes.org
+++ /dev/null
@@ -1,97 +0,0 @@
-#+title: Class notes
-
-
-* class 1 /sun sep 17 13:04:43 2023/
-** Les Reseaux locaux (LAN)
-Cable 10 mbps ou moins = Ethernet
-Cable 100 mbps = Fast Ethernet
-Cable 1000 mbps ou plus = Giga Ethernet
-
-** MAC Address :
-First three Bytes : vendor
-Last three Bytes : Unique ID
-(In Hexadecimal)
-
-TODO: CSMA/ CA CD
-
-** RJ-45 connecteurs
-**** Straight
-**** Crossover (croisé)
-**** Rollover (console)
-
-** IPV4 classes :
-- Classe A : 0 - 127  /8
-  - 0.0.0.0/0 : route par default
-  - 127.0.0.0/8 : bouclage
-- Classe B : 128 - 191  /16
-  - 169.254.0.0/16 : APIPA
-- Classe C : 192 - 223  /24
-- Classe D : 224 - 239
-  - Multicast
-- Classe E : 240 - 255
-
-** Adresses privées:
-- Classe A : 10.0.0.0 - 10.255.255.255 /8
-- Classe B : 172.16.0.0 - 172.31.255.255 /12
-- Classe C : 192.168.0.0 - 192.168.255.255 /16
-
-
-8   7   6   5   4   3   2   1
-128 64  32  16  8   4   2   1
-256 128 64  32  16  8   4   2
-/24 /25 /26 /27 /28 /29 /30 /31
-
-500
-150
-60
-30
-20
-15
-** 500 hosts :
-
-Addresse: 10.0.0.0 /23
-
-500 - 256 = 244
-
-First IP : 10.0.0.1 /23
-Last IP : 10.0.1.254 /23
-@B IP : 10.0.1.255 /23
-Mask : 255.255.254.0
-
-** 150 hosts :
-
-Addresse: 10.0.2.0 /24
-First IP: 10.0.2.1 /24
-Last IP: 10.0.2.254 /24
-@B IP: 10.0.2.255 /24
-Mask: 255.255.255.0
-
-** 60 hosts :
-Addresse: 10.0.3.0 /26
-First IP: 10.0.3.1 /26
-Last IP: 10.0.3.63 /26
-@B IP: 10.0.3.64 /26
-Mask: 255.255.255.191
-
-** 30 hosts:
- Addresse: 10.0.3.63/8
- First IP: 10.0.3.64/8
- Last IP: 10.0.3.96/8
- @B IP: 10.0.3.97/8
- Mask: 255.255.255.158/11
-
-** 20
-Addresse: 10.0.3.97/8
-First IP: 10.0.3.98/8
-Last IP: 10.0.3.128/8
-@B IP: 10.0.3.129/8
-Mask: 255.255.255.126/11
-** 15
-Addresse: 10.0.3.129/8
-First IP: 10.0.3.130/8
-Last IP: 10.0.3.144/8
-@B IP: 10.0.3.145/8
-Mask: 255.255.255.110/12
-
-* Class 2Sun /Sep 24 09:09:28 2023/
-** CCTV (finally)
