add "table of contents" h2 section to all READMEs

contents/ethernet_lan_switching/README.md

@@ -1,5 +1,16 @@
 # Ethernet LAN Switching
 
+
+## Table of contents
+* [What is a LAN ?](#what-is-a-lan)
+* [Ethernet Frame](#ethernet-frame)
+* [MAC Address](#mac-address)
+* [ARP](#arp)
+* [Ping](#ping)
+* [MAC Address Table](#mac-address-table)
+* [Examples](#examples)
+
+
 ## What is a LAN ?
 A Local Area Network is a network contained within a relatively small area.
 LANs use L2 layer frames.

contents/interfaces_and_cables/README.md

@@ -1,5 +1,18 @@
 # Interfaces and Cables
 
+
+## Table of contents
+* [Network Protocols](#network-protocols)
+* [Bits and Bytes](#bits-and-bytes)
+* [Ethernet](#ethernet)
+* [Ethernet Cable Standards](#ethernet-cable-standards)
+* [UTP Cables](#utp-cables)
+* [Copper UTP Cables](#copper-utp-cables)
+* [Fiber-optic UTP Cables](#fiber-optic-utp-cables)
+* [Fiber-optic Cable standards](#fiber-optic-cable-standards)
+* [UTP vs Fiber-optic Cabling](#utp-vs-fiber-optic-cabling)
+
+
 ## Network Protocols
 
 Agreed upon system of communicating between network devices.

contents/intro_to_cisco_cli/README.md

@@ -1,9 +1,21 @@
-# Cisco IOS (CLI)
+# Intro to Cisco CLI
 
-## What is it and what is it used for ?
+
+## Table of contents
+* [Cisco IOS](#cisco-ios)
+* [How to connect to a Cisco device](#how-to-connect-to-a-cisco-device)
+* [CLI](#cli)
+* [EXEC Modes](#exec-modes)
+* [Enabling Password](#enabling-password)
+* [running-config / startup-config](#running-config--startup-config)
+* [Saving the configuration](#saving-the-configuration)
+* [Password encryption](#password-encryption)
+
+
+## Cisco IOS
 Operating system used on Cisco devices for configuration.
 
-## How to connect to a Cisco device ?
+## How to connect to a Cisco device
 
 ### Console Port
 

contents/network_devices/README.md

@@ -1,5 +1,15 @@
 # Network Devices
 
+
+## Table of contents
+* [Network](#network)
+* [Server](#server)
+* [Client](#client)
+* [Switches](#switches)
+* [Routers](#routers)
+* [Firewalls](#firewalls)
+
+
 ## Network
 A computer network is a digital telecommunications network which allows nodes to share resources
 

contents/osi_model_and_tcp_ip_suite/README.md

@@ -1,5 +1,12 @@
 # OSI Model and TCP/IP Suite
 
+
+## Table of contents
+* [Networking models](#networking-models)
+* [OSI Model](#osi-model)
+* [TCP/IP](#tcpip)
+
+
 ## Networking models
 Networking models categorize and provide structure for networking protocols and standards.
 
@@ -81,7 +88,7 @@ Open Systems Interconnection model
 ![](docs/pdu.png)
 
 
-## OSI funny acronyms
+### OSI funny acronyms
 ![](docs/osi_acronyms.png)