In this article I’ll describe a few ways to verify over the network if a remote TCP port on a host is open or not. This is a popular troubleshooting method to identify if a specific service or application is running on a remote server or computer. As you might know already, when an application […]

Ubiquiti manufactures networking products (routers, switches, wireless etc) that can serve in a broad range of implementation cases, from Home networks up to large Enterprise environments. The USG (UniFi Security Gateway) and EdgeRouter devices are two product lines that target a similar market – I would say the SOHO and SMB enterprise market (although there […]

TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are both Layer 4 transmission protocols in the OSI model. However, these two protocols are quite different. From a high level view you could say that TCP is reliable and UDP is unreliable. Why then would we use UDP?

UDP Characteristics Due to UDP being […]

Ethernet Switches are the backbone of any network, no matter if it’s a home, office or enterprise network. Even though most of our communication nowadays is carried out wirelessly (WiFi, Mobile 3G-4G-5G etc), there ARE a lot of cases whereby network connectivity has to be implemented the “old-school” wired way. And that’s where Ethernet Switches […]

CIDR was invented to facilitate better and more efficient allocation of IP addressing and especially IPv4 addresses which started running out pretty fast when the whole Internet accelerated its pace during the last 2-3 decades. What is Classless Inter-Domain Routing (CIDR) As you know, an IPv4 address consists of 32 bits and is represented as […]

If you have studied the OSI model with its 7 Layers that describe a communication or computer network system, you should know that the Ethernet standard lies in Layer 1 (Physical) and Layer 2 (Data-Link) of the OSI model.  In this article we will focus on the physical (Layer 1) part of Ethernet, which mainly […]

Networking is at the center of all information sharing and Internet activities, and most homes and businesses have some sort of networking technology used for internet access and for enabling the business communications and functions. However, many people struggle with some of the fundamental concepts involved in computer networking. Both Local-Area Networks, or LANs, and […]

The internet and intranet are closely related terms. Some individuals may get these terms confused or use them interchangeably. While there are similarities, the internet and intranet are used for very different purposes. What Is an Internet Network? When you visit a website or use a mobile app that requires an internet connection, you are […]

Computer networks keep changing the way we live and do things in the 21st century. This is because virtually every computing activity or information sharing we do today depends on one form of network or another. The Internet is a very good example of a computer network that allows users to get information from any […]

Computer networking has been around for several decades, which is the backbone of what we all know as the Internet today. The Internet is simply a network of networks, which means there is no such thing as a standalone computer on a network. For a user or host computer to participate in data and resource […]

In this blog I usually share practical configuration examples and how-to guides about Cisco networking devices and technologies (routers, switches, ASA firewalls etc). However, there are a lot of people out there interested in more generic and fundamental networking topics because they either just starting out in this field or are learning the basic concepts […]

As Network Engineers we need to be versatile and troubleshooting-savvy in our work environment. In addition to having strong knowledge of networking protocols and commands on network devices (routers, switches, firewalls etc) we need also to have very good knowledge of IP and other networking related commands on end-point devices such as Windows computers, Linux […]

A few months ago I was involved in a project where we had to design a network redundancy scenario with two physically separate networks in two different buildings (the sites were a few kilometers away from each other). The main requirement was to provide Inbound Internet Access to two Server Pools (Linux Servers in High […]