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How to detect rogue DHCP servers on a Network

In this tutorial, the mechanism to detect a rogue dhcp server with nmap is understood. Rogue dhcp servers are setup on the network by attackers to create disruption of services. nmap is installed on a system. nmap is used to scan, UDP port 67, which is used

How to display received packets and fields

This video tutorial demonstrates how scapy tool can be used to display the packets and fields which are recieved in response to a packet which was sent. ——————————————————————————————————————————– This is a sample preview from the Video Course   Network Testing Video Course Price $99

Network Design with 100 users

Requirement A network consists of two sites. Each site has 100 users. The routers on one of sites, is connected to the internet through which the LAN users get access to the internet. The users at different sites should be able to access each other. Identify appropriate

What is gateway in networking

Assume the following two scenarios – 1. A PC with IP address 192.168.1.2 with subnet mask tries to access a PC with IP address 192.168.2.1 with subnet mask 255.255.255.0. 2. A PC with private IP address 192.168.1.2 with subnet mask 255.255.255.0 tries to access a website on

How is a packet forwarded on a router

When an IP packet is received on a router, the destination IP address is looked into. The network address corresponding to the IP address is looked into the routing table of the PC. If the network is a directly connected network, the packet is sent out using

What happens when an IP packet reaches a router

  In the above diagram, PC1 is configured with the IP address 192.168.1.2 and subnet mask 255.255.255.0. The router is configured with the IP address 192.168.1.3 and subnet mask 255.255.255.0. When PC1 pings the IP address of the router, the source IP address in the IP packet

How does a switch populate cam table

The cam table of a switch contains the mac-address to the port number mapping. It is built dynamically. In the above diagram, PC1 and PC2 are connected to E0 and E1 ports on the switch. When data is generated from PC1 to PC2, an ethernet frame is

Home Network Design with IPCamera access from Internet

Case In a home, there are 5 users, of which 2 are desktop users and remaining wireless. All users should have access to the internet. An IP camera is to be integrated in the home network which should be accessible from the internet.   Solution There are

Home Router Features

Home Router features A home network basic topology typically consists of 2 networks, the internal and external network. If the internal network corresponds to the LAN network to which the home users belong to and the external network, corresponds to the internet. The router typically has two