I first got acquainted with TFTP at the beginning of my networking career. The first use-case of TFTP protocol is when I first upgraded the IOS firmware of a Cisco router using a little software utility called “TFTPD32”. Trivial File Transfer Protocol (TFTP) software provide a key service to many network and system administrators for […]
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Every network engineer is familiar with Cisco, and with its multiple brand acquisitions, it’s even become a household name for consumers in addition to business professionals. Cisco isn’t the only major player in the hardware and TCP/IP networking game, however. This technology giant has at least a dozen formidable competitors, many of which have developed […]
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Layer2 and Layer3 switches are the foundation of any network. After all, any network devices (routers, firewalls, computers, servers etc) have to be connected to a switch. Sooner or later, as a network engineer you will be faced with the task of deploying a switch network for a customer or for your own company. Therefore, learning […]
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With the rise of distributed networks, finding a secure way to transfer files and data is essential. That’s where software products like Secure File Transfer Protocol, better known as SFTP, comes in. File Transfer Protocol has been around since 1971; the encrypted version was developed in 1994. This popular file transfer communication protocol is able […]
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In this article, we will discuss a couple of core concepts of network switching which are about Access and Trunk ports and how to configure them using “switchport mode access” and “switchport mode trunk” commands on Cisco switches We will also delve into what a VLAN is, why they’re used and how all of this […]
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A few decades ago, flat networks were the norm. I remember in my very first job as a network engineer, most of our clients’ networks consisted of a single broadcast domain (VLAN) and a huge single flat Layer 3 network (usually in the 10.0.0.0 range). As time passed by and networks started to become bigger […]
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The Cisco ASA firewall offers excellent protection for Denial of Service attacks, such as SYN floods, TCP excessive connection attacks etc. Using the new Policy Framework functionality, the ASA administrator can configure granular controls for TCP Connection limits and timeouts. For example, we can control and limit the maximum number of simultaneous TCP and UDP connections […]
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When it comes to authentication services in networking and IT systems in general, the best practice is to have a centralized authentication system which contains the user account credentials in a secure way and controls all authentication and authorization. This is why Active Directory in Microsoft environments is such a useful and powerful authentication scheme. […]
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This tutorial marks the beginning of a series of network security and penetration testing articles that I will be posting on this website. The purpose of this article is to describe how to perform a simple NMAP scan of an IP range/subnet on a network. There are hundreds of scan options with NMAP but I […]
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Professional Certifications are crucial in the IT world. From an employer’s perspective, they demonstrate deep knowledge in complex areas and verification of your abilities as a professional. For entry-level and veteran IT professionals, they reflect much more. The certification process allows you to grow, progress in your career and drive the passion that contributes to […]
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In this article we’ll discuss and examine the Syslog Protocol which runs over its default UDP port 514 (or the secure TCP port 6514), and also describe the characteristics and usefulness of Syslog in networks. All computer systems and network devices generate a historical record of events that take place on the device. This record […]
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Prepare to peek under the covers of how your data can travel from as little as a few inches to thousands of miles from device to device and through tens of network devices in the path. In this article, we will explore the differences between a layer 3 Internet Protocol (IP) Packet and a layer […]
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The company Meraki was founded in 2006 and started out as a research project called Roofnet within MIT (Massachusetts Institute of Technology) which had the aim of providing outdoor Wireless Internet access to the City of Cambridge. In this article we will discuss the Cisco Meraki brand and answer some Frequently Asked Questions that many […]
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