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 […]
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The firewall is the cornerstone of security in computer networks and I.T in general. In this website I have been talking extensively about the Cisco ASA firewall which is a classic example of a hardware network firewall. However, there are some other types of firewalls used in large enterprises, SMB or even home networks. Some […]
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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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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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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?
Table Of Contents
UDP Characteristics Due to UDP being […]
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PuTTY is a free terminal emulation tool that’s been available for 20 years. Originally released for Microsoft Windows, this versatile remote administration tool can be used to access workstations, servers, network devices etc using various protocols such as secure shell connection (SSH), Telnet, Rlogin etc. While it continues to be popular for accessing network devices […]
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In the Networking and IT world we usually design and implement networks and server infrastructure taking for granted that the hardware and applications will withstand any volume of traffic. Stress Testing a network or IT system with high volume of traffic will give us significant insights about the behavior of such systems in abnormal conditions […]
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DHCP stands for Dynamic Host Configuration Protocol. Basically it’s a mechanism which assigns IP addresses to computers dynamically. Usually DHCP is a service running on a server machine in the network in order to assign dynamic IP addresses to hosts. However, Cisco Routers (and other devices such as ASA firewalls etc) can work also as […]
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In this tutorial I will describe the configuration of an interesting network scenario that I’m sure many of you will find helpful. This scenario is applicable in many real world situations, mainly in small to medium networks. The network scenario is as follows: We have three different internal LAN networks which host user computers and […]
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As network engineers and administrators, we mostly focus on managing and configuring hardware devices such as routers, switches, firewalls, load balancers etc. We rarely deal with software management tools which are equally important in a corporate network. Without knowing the health, performance, availability and quality of your network is like running with closed eyes. Network […]
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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 […]
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Whenever Microsoft releases security patches even for unsupported Operating Systems (such as Windows XP, Vista etc) then you must act immediately (as a company or administrator) because it’s always a serious issue. This is what happened in May 14 when Microsoft released security patches for a critical software vulnerability affecting the Remote Desktop Protocol (RDP). […]
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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 […]
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