What is Time to Live (TTL)

What is Time to Live (TTL)

TTL , which stands for Time to Live is a field which is available in the IP header. Take a scenario where a users pings an IP address from his PC. When the IP Packet is constructed for the ping , the TTL value is embedded inside the IP Packet header. Windows based computers...

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Port number of telnet

Port number of telnet

The article describes the port numbers which is used by telnet protocol. Telnet uses a client server architecture and uses TCP as the transport layer protocol. In the above diagram, a PC and a router is connected to the switch. The IP address of the PC is 192.168.1.2 and that of the router is...

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How does a switch learn mac-addresses

How does a switch learn mac-addresses

                              The article describes the process of how a switch learns mac-addresses. In the above diagram, PC1 and PC2 are connected to ports FA0/1 and FA0/2 on the switch. Assume a scenario where the switch has been powered on. After...

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What is static routing

What is static routing

The article aims to explains the concept of static routing. In the above diagram, PC1 and PC2 are on two different networks (192.168.1.0 and 192.168.2.0). PC1 and PC2 are connected to the switches, which are connected to the routers. The routers are connected via a point to point link. For PC1 and PC2 to...

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What is port security

What is port security

Port security is a feature which is available on network switches to block attacks which are based on mac-addresses. Mac-spoofing and cam flooding are two attacks which are based on mac-addresses. In a mac-spoofing attack, an attacker impersonates a valid user, by spoofing the users mac-address. The switch, would then be confused as to...

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How to find ip address on a network

How to find ip address on a network

The article describes two tools which can be used to find the ip addresses which are currently configured on a network. A typical scenario, where this situation is encountered would be a network where a DHCP server is providing dynamic IP addresses to the clients and a File Server needs to be configured with...

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How to share an internet connection

How to share an internet connection

A home user has an internet connection at home. The internet is enabled on PC1, through a modem. Internet connection is available only on PC1 and is not shared among any other users at home. There are three users at home. Two users have PC’s (Including PC1 connected to the internet) and another user...

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What is the difference between hub and switch

What is the difference between hub and switch

The article explains the fundamental difference between hub and switch. In the diagram above, 3 computers are connected to a hub and a switch respectively. On the hub, let’s assume a scenario where two PC’s are attempting to communicate with each other.Take a scenario where a PC pings another PC. Before transmission, the network...

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What port does ping use

What port does ping use

The article explains the reason as to why there are not ports associated with ping. In the above diagram , there are two PC’s , PC1 and PC2. When PC1 initiates a ping to PC2, the ping packet is constructed on PC1. The source IP address of the IP header carrying the ping packet...

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What is a native vlan

What is a native vlan

The post explains the concepts of native vlan and how it works in a real time environment. In the above diagram, PC1 is connected to port 2 on the switch SW1. The port is a member of vlan 2. PC2 is connected to port 3 on SW1. The port is a member of vlan...

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How does port forwarding work

Port forwarding is a feature which is supported on routers and gateways. It is commonly used in two scenarios. Systems which are on the LAN network and is not reachable via the internet can be made to be accessible by this feature. In the second scenario, the actual service which is to be reached...

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What is URL Filtering

What is URL Filtering

URL filtering is a feature which is implemented on networking components like routers, firewalls, Web filtering devices. This feature allows the user to specify a URL on the component. Once the URL is configured, the users which are behind these devices would not be able to access the specified URL. The following outlines the...

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What is NAT-T

What is NAT-T

NAT-T is the feature by which IPSEC end stations can communicate in the presence of a NAT enabled device. The following describes the generic issue with IPSEC and NAT. In the attached diagram , R1 and R2 are connected via an IPSEC tunnel. R1 and R2 are also NAT routers. Let’s take the following...

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Communication between Web client and Web server

Communication between Web client and Web server

This tutorial explains the traffic flow, technology and protocols involved when a Web client( browser) and a Web Server (Website hosted on a Server). In the above diagram , the PC is on the internal network with the IP address 192.168.1.2. The default gateway of the PC is configured as 192.168.1.1 , which is...

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Communication between two computers connected to a switch

Communication between two computers connected to a switch

The tutorial explains the end to end communication between two computers connected to a switch. In the above diagram the computer with IP address 192.168.1.2 (PC1) pings the computer with IP address 192.168.1.3 (PC2). The following are the sequence of events which would happen 1.The user on the computer with IP address 192.168.1.2 pings...

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Internet connection sharing on windows 7

Internet connection sharing on windows 7

The article demonstrates how to setup a network by sharing internet in windows 7. In the diagram above, the Windows 7 PC has two network cards. One of the network cards is connected to the internet. The ISP provides a public IP address for the network card which is connected to the internet. The...

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How Network Protocols work

How Network Protocols work

A protocol in computer networking can be defined as the ‘language’ for computer network communication. Whether you are browsing the internet, sharing files or printing a file, a network protocol is always involved. Network protocols are developed by protocol design and development engineers. Different protocols would be involved to achieve end to end computer...

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Test your knowledge on basic concepts of computer Networking

The networking questions test your knowledge on the basic concepts of networking. Once attempting the questions, if you feel that you still have more to learn, join our online training. 1. A user opens a browser and types in a website name. The user then views the website on the browser. Which of the...

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Computer Networking concept

Computer Networking concept

What is Computer Networking Computer networking is the technology by which two or more computers can communicate with each other. Take an example, where two people, Andrew and Susy wishes to communicate. If the communication between them has to be successful, both of them should speak the same language. If Andrew speaks and understands...

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Questions on VLAN

Question -1 How many untagged VLAN’s can a switch port be a member of a)1 b)Unlimited c)4096 d)Dependent on the capacity of the switch Question -2 On a switch , port 1 and port 2 are configured as members of vlan 2 and vlan 3 respectively. Which of the following is true a)Broadcast traffic...

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Questions on Routing

IP Routing Fundamentals – Exam The answers for the questions are provided at the end of the page Question 1 A router is required for communication between two PC’s with IP address 192.168.1.63/26 and 192.168.1.65/26 respectively. A)True B)False Question 2 How many routing entries would be available on a routers routing table which has...

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How to setup a LAN with multiple computers with dynamic IP address

How to setup a LAN with multiple computers with dynamic IP address

Requirement A LAN has to be setup with multiple computers. The computers need to receive dynamic IP addresses. Identify the necessary components, features and services to setup the LAN. 1. A switch is required for connecting the computers and to form a network. 2. Since the computers require dynamic IP addresses, a DHCP Server...

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How does Syn flooding work

How does Syn flooding work

Syn flooding exploits the SYN bit of the TCP header in a TCP/IP Packet. In the Syn flooding attack, the attacker crafts the packets with invalid source IP addresses with the Syn bit enabled. Refer the below diagram. The post explains the anatomy of Syn flood attack and how a Cisco IOS Firewall can...

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Routing between two PC’s on different networks

Routing between two PC’s on different networks

Scenario The scenario is as shown in the diagram. Requirement PC1 should be able to access PC2 Watch the video to achieve the configuration

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Remote connection from Windows 2008 to Windows XP using VNC

Remote connection from Windows 2008 to Windows XP using VNC

Scenario The Windows XP and Windows 2008 PC is connected to the switch. Windows 2008 is the domain controller. Requirement The Windows 2008 PC should be able to remotely view the Windows XP using VNC. Watch the Video Configuration of to achieve the requirement

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Remote Desktop Connection from Windows XP to Windows 2008

Remote Desktop Connection from Windows XP to Windows 2008

Scenario The Windows XP and Windows 2008 PC is connected to a Cisco 2950 switch. Windows 2008 PC is the domain controller. Requirement The Windows XP PC should be able to remotely connect and view the Windows 2008 PC.

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Intervlan routing with Cisco router and switches

Intervlan routing with Cisco router and switches

Scenario – PC1 is connected to a port belonging to VLAN 2 on the sw1, PC2 is connected to a port belonging to VLAN 3 on sw2 and PC3 is connected to a port belonging to vlan 4 on sw3. A port on the switch is connected to the router and is configured as...

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Intervlan routing – Configuration Scenario

Intervlan routing – Configuration Scenario

Scenario PC1 is connected to a port on the switch which is a member of VLAN 2. PC2 is connected to a port on the switch which is a member of VLAN 3. A port on the switch is configured as a trunk port , which is connected to the router. Requirement PC1 should...

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How to Configure static route scenario- Configuration on Cisco Routers

How to Configure static route scenario- Configuration on Cisco Routers

Requirement PC1 should be able to ping PC2

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How to configure Rip v1 on Cisco router

Rip version1 configuration on Cisco router View more presentations from designnetworks

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How to configure hostname, time and login message for Cisco switch

Configuring hostname, time and login message for Cisco switch View more presentations from designnetworks

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How to configuring hostname, time and login message on Cisco router

Configuring hostname, time and login message on Cisco router View more presentations from designnetworks

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How to configure static Mac address for Cisco Switch

Mac address-table static View more presentations from designnetworks

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How to configure telnet on cisco switch(1950)

How to configure telnet on cisco switch(1950) View more presentations from designnetworks

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How to configure different Spanning tree port status

How to configure different Spanning tree port status View more presentations from designnetworks

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How to Save, backup and restore IOS on Cisco router

How to Save, backup and restore IOS on Cisco router View more presentations from designnetworks

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How to create Security on Cisco switch

How to create Security on Cisco switch View more presentations from designnetworks

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How to Configure ip address for router interfaces

How to Configure ip address for router interfaces View more presentations from designnetworks

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How to Configure password for telnet and console port of a switch

How to Configure password for telnet and console port of a switch View more presentations from designnetworks

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How to configure password, secret password and password encryption for Cisco router

How to configuring password, secret password and password encryption for Cisco router View more presentations from designnetworks

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How to configure password, secret password and password encryption for switch

How to configure password, secret password and password encryption for switch View more presentations from designnetworks

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How to configure SSH on Cisco switch

How to configure SSH on Cisco switch View more presentations from designnetworks

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How to configure Default Routing

How to configure Default Routing View more presentations from designnetworks

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How to configure DHCP Server on windows 2008

How to configure DHCP Server View more presentations from designnetworks

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How to configure Dynamic nat

How to configure Dynamic nat View more presentations from designnetworks

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How to setup a network for a university with multiple departments

Network Design – University with multiple departments Scenario – A network has to be setup in a university. The campus is spread across 20 acres. The university has 10 departments, with an average of 50 users in each department There are 10 blocks in the university. The users should have the mobility to access...

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How to setup a network for a hotel chain with multiple locations

Network Design – Hotel with multiple locations Scenario A hotel chain has their presence at 5 geographical locations. The reservation system is which is managed on a centralized server at the main location, should be accessible from all the locations. Alternatively, all the locations should be connected to each other. Components and features 1.Internet...

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How to design a network for a hotel

Network design – Hotel Scenario A network has to be setup for a 5 star hotel. The hotel has 5 blocks, with a pool area. Every block has approximately 100 rooms. Each room should have internet access. The users in the pool area and the lobby should have wireless internet access. Internet access is...

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How to setup a hotspot in a coffee shop.

Internet hotspot design – Coffee shop Scenario A coffee shop needs wireless internet access for its users. The users would be provided with a pre-paid ticket containing a onetime password to login for the appropriate duration for which the ticket is valid. What components and features would be required. Components and Features 1.Router –...

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How to setup an internet cafe with automated billing and user registration

Internet cafe design- Automated billing and user registration Scenario An internet café has to be designed. The maximum number of users in the Café is 50. The process of user registration and billing has to be automated. The café has an ADSL internet connection from the ISP. What are the components and features which...

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