Author: Marcin Bialy

If you work in IT or networks, you’ve probably heard of the ISO/OSI model. It may seem like theory for students, but in practice, it’s the foundation for understanding how network communications work. Even if we talk about TCP/IP every day, the ISO/OSI model is still your guide for designing and troubleshooting. In the 1980s, […]

Understanding IP addressing, network masks, and subnetting is essential for anyone working with computer networks. In this guide, we’ll cover the fundamentals of IP addresses, subnet masks, address ranges, and how to design efficient IP addressing plans. What is an IP address and network mask? Every IP device with an IP address operates inside a […]

Those who are familiar with Cisco ISE and have been using it for quite a few years have become accustomed to the licensing system known from ISE 1.x and 2.x. The well-known Base, Plus and Apex licenses end with the release of ISE 3.x. In their place, licenses of the so-called Tier Based, i.e. Essentials, […]

Cisco ASA EoL EoS – what does EoL / EoS status of Cisco products mean, what does it mean for Cisco ASA lines and could be a replacement line of product?

End-of-life (EoL) is a general term used when the vendor plans to cease the production of a certain product or product line. Taking into account that millions of end clients around the world might be using the product, the EoL comes with a group of milestones that all together form the End of Live of […]

There is no need to convince anyone of the fact that phishing is one of the most widespread methods of attacks on enterprises. The Data Breach Investigation Report 2022 from Verizon shows that phishing is the second greatest (after login credential theft) threat for companies.  It’s worth asking yourself, is there a mechanism that preempts […]

Before the era of UTM (Unified Threat Management or next-generation firewall), we most often dealt with stateful firewall devices. The principle of operation of the stateful firewall is primarily operating on the headers of the third network layer (L3) and the fourth transport layer (L4) of the OSI model. Thanks to the understanding of headers […]

According to Verizon in their 2022 report, over 82% of security incidents were related to human-side negligence, such as password leaks or phishing. Moreover, passwords being stolen have various lengths and degrees of complexity. Considering the scale and improvements in methods used by malicious actors, it’s not that difficult to see even a strong password […]

Why is it important to take a comprehensive approach to secure Internet interfaces, instead of focusing on one area, e.g. a firewall?   In this article, we will take a shot at answering this question, showing potential Internet interfaces that can be critical in case of attack. You will learn what firewall network security is and […]

When dealing with networks, both wired and wireless, we can’t fail to mention the security issue. In the case of wireless networks, many users are unaware of the hazards lurking when switching between networks and using unprotected, unverified wireless networks. This article will answer your questions on securing the Wi-Fi network and making it resistant […]