Information Technology BLOG

 Hello, We're gonna talk about DHCP snooping, DHCP SNOOPING is a technology that prevents our local network users or any device that should be asigned an ip address to contact a suspiciours dhcp server, So we need to understand how DHCP process works first, in order to understand how we can protect our local users and their IP attributions. There are four steps through which we need to pass in order to attribute an ip address from our internal dhcp servers or server/ First of all the client sends a DHCP discovery request in the form of a broadcast, then the DHCP server will go ahead and respond to that request with a DHCP offer frame, our client then goes ahead and accepts offer by issuing back a DHCP request for the address that was offered and then the DHCP server will send back an acknowledgment saying yes you can go ahead and use that ip and then it's installed in its database and our user starts to connect in a normal way on our internal network. Example: The problem...

DDOS stands for "Distributed Denial of Service" A DDOS attack is carried out by a network of machines, hence the notion of distributed attacks These machines have been corrupted beforehand by cybercriminals through the spread of malware. This network of infected machines is also called botnet. The cybercriminal will execute a DDOS attack by ordering the botnet to saturate the service with many requests until it becomes unavailable, It is the concept of denial of service. DDOS can be on a specified service, it can also be a network link, an infrastructure, a website, an application, etc... It is noted that with the rise of the IoT or Internet of Things DDOS attacks gain in intensity since cybercriminals enroll unsecured IoT equipment in botnets. Denial of service will prevent real users of the service from using it. Another variant is DDOS attacks based on reflection and amplification, In this case, the cybercriminals will use machines accessible on the internet and there...

 Hierarchial Network Design What is a FLAT NETWORK? Flat Networks are networks in which all computers, servers, printers are connected together using just layer 2 switches, there is no use of subnets in flat networks, in addition,  all devices are located in the same broadcast domain and broadcast trafic is transmitted to all devices on the network and because of that BANDWIDTH is not used effectively. FLAT networks CAN NOT meet the needs of most enterprise networks or small to medium size business. What is a Hierarchical NETWORK? Hierarchical Models allow to design the network by using different layers, Layers of the Hierarchical Network are devided into specific functions that are categorized as CORE, DISTRIBUTION and ACCESS Layers. This categorization privides FLEXIBLE design options and ease scaling of  network devices. Here is an overview that explains the difference between a flat Network VS Hierarchical Network: As you can see that in the FLAT network model, a...

Here you can download all videos of CCNP ENCOR 350-401 From this page for FREE. We have uploaded only the first 2 modules for the moment because we need to see whether people are interested or not in this series of videos. If we have over 200+ downloads we will be uploading the rest of the videos for free also. FREE CCNP ENCOR (350-401) Module 2 Videos Module 2 : NETWORK DESIGN BASICS Video N° 3 : Cisco Switch Types : http://upload-4ever.com/d/IdB2 Video N° 2 : Network Topology Architectures : http://upload-4ever.com/d/IdAq Video N° 1: Hierarchical Network Design : http://upload-4ever.com/d/IdAh Module 1 Videos Module 1 : BASIC SWITCHING CONCEPTS Video N° 4 : LAB Multi Layer Switching Configuration : http://upload-4ever.com/d/IdAV Video N° 3 : Multi Layer Switching: http://upload-4ever.com/d/IdAA Video N° 2: VLAN and Trunking : https://www.upload-4ever.com/lmd7jm33geuq Video N° 1 : Basic Switching Concepts : https://www.upload-4ever.com/mysj0lacvev5 The ads that are showing wi...

Through this article we will jump into the very first step to learn how to configure a port on a cisco switch.   In order to configure a small network as a beginner first you need to know what is a switch   ( click me ). Basically cisco equipements are the most common switches so we are going to use the cisco syntax in this article, if you are interested in other equipements like huawei or, HP, ARUBA or others just leave a comment. 1 - Log to the switch using the login and the password  (use the command >enable) 2 - Than you should enter the previliged mode wich is (#); using the command #configure terminal you will access this mode 3 - Choose the port that you need to configure examlpe:      #interface fastethernet 0/1          Than type this command      #switchport mode access       switchport means this port is going to switch packets     and it`s mode is ACCESS, means it...

Installing Python on your Desktop First of all, we need to install Python, In order to do that, we should go to PYTHON's official website and download it from there. Here is a link to download Python https://www.python.org/downloads/ Python is available for Linux, Windows, and macOS, choose the installation file based on the type of OS you're using. On windows 10, The installation is very simple you'll need to download the executable and then simply launch it. Do not forget to select "ADD PYTHON (Python version) to PATH" at the beginning of the installation process. After the installation is complete and in order to test Python you can open a simple Command Line Prompt than just type "Python" If it displays this kind of message : Then everything is fine. Try this message : >>>print("Hello world") and it will print out Hello World message  This is...

What is a router? Routers are responsible for transmitting packets from one end host on the internet, maybe a laptop to and from other end-hosts that are connected to the internet like a web server that we are accessing. Routers are not computers that you might recognize, routers are specialized pieces of computer hardware that is built to do one task over and over and over again and that determines where a packet should go.  If the router only has two connections then when a packet comes in on one connection, it has to go out on the other and to some degree, there's no real point to have a router there at all same thing with the other direction because a router is on a destination for traffic it's just there to route traffic to move it towards a destination that's an important distinction between end hosts and routers. An end host can be a PC or a server... Routers typically don't initiate that much traffic, they can initiate a little bit maybe usi...