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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Companies these days need to deal with and manage vast inventories of network and IT assets. Keeping track of these assets, tagging them, and knowing their status at all times is essential to the operations of any modern company. Image Source As you’d expect, this is a big job but network inventory software makes it […]
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For businesses, the task of network and IT infrastructure monitoring remains highly important. A company cannot afford to ignore the security and performance of its network and IT resources. Nagios remains one of the most popular solutions for IT infrastructure monitoring today. An entire suite of software allows businesses to take control and have visibility […]
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A Small Form Factor Pluggable (SFP) Port on a network switch is an Ethernet Interface which has been designed to allow a small module (which contains a connector and small circuit board) to be inserted into the switch. This device is called an SFP Module. There are different types of SFP modules and SFP ports, […]
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All Cisco ASA firewall models from 5510 and higher (including the newer generation of 5500-X appliances), include an extra dedicated Ethernet interface for management. In this article we will provide a basic example of configuring network settings to the dedicated management interface and also SSH access in order to connect to the appliance through the […]
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