The following article describes how to configure Access Control Lists (ACL) on Cisco ASA 5500 and 5500-X firewalls. An ACL is the central configuration feature to enforce security rules in your network so it is an important concept to learn. The Cisco ASA 5500 is the successor Cisco firewall model series which followed the successful […]
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An Access Control List (ACL) is a list of rules that control and filter traffic based on source and destination IP addresses or Port numbers. This happens by either allowing packets or blocking packets from an interface on a router, switch, firewall etc. Individual entries or statements in an access lists are called access control […]
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Syslog is the De Facto standard used in Networks for sending/receiving Log messages from IT systems, network devices, hosts etc. The Syslog protocol runs over port UDP 514 and is based on the IETF RFC 5424 standard. Almost all network connected devices (routers, switches, firewalls, Unix systems, Windows systems etc) support the Syslog protocol for […]
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As network engineers we are usually assigned various tasks related to the life-cycle of networks, starting from the initial design, procurement, installation of network equipment and then management and monitoring of existing networks. In the latter phase (management and monitoring of networks) we are constantly faced with major or minor problems such as links going […]
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IP version 6 (IPv6) is the new version of the Internet Protocol (IP), intended to replace the older IPv4 which is still employed on the vast majority of Internet hosts. IPv6 increases the IP address size from 32 bits to 128 bits to support a much greater number of addressable hosts. IPv4 can support 232 […]
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In this tutorial we will see a special case of high availability scenario using HSRP with object tracking. Most modern enterprise networks in today’s deployments require some form of high availability depending on the uptime needed and the criticality of the service. The network infrastructure elements that are usually needed to be highly-availability include network […]
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There are some networking terms and concepts that are so fundamental and important that every TCP/IP networking professional must know them by heart. One of these fundamental concepts is VLAN Trunking. What is VLAN Trunking in Networking? A VLAN Trunk falls into Layer 2 of the OSI model and is related to network switching. When […]
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Network Switches form the backbone of computer networks and are one of the main building blogs of a Local Area Network (LAN). A network switch usually operates at Layer 2 of the OSI model (working with the Ethernet protocol) but there are switch models that implement also routing, which can be considered as Layer 3 […]
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Technology and IT training is booming as professionals must keep sharpening their skills and knowledge to stay competitive. However, technology is not the only field that people pursue additional knowledge and training. Many individuals want to expand their education and knowledge in a broad range of fields such as marketing, software development, information security, business, […]
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Udemy is an online course platform that lets you learn pretty much anything at any time. Once you’ve purchased a course, you get lifetime access to it so you can truly train at your own pace. People have been using this site for progressing in their current career, working towards a career change, and learning more about their […]
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One of the most useful and popular commands used on Cisco devices is the “show interface” command. It can be very useful at troubleshooting connectivity issues and physical port issues, check the status of physical ports, watch how much traffic is passing through the interface, which IP address is assigned to the interface (for Layer3 […]
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Online learning platforms exploded in popularity a few years ago. Recently, a handful of platforms have fought their way to the top in the market of MOOCs (Massive Open Online Course). Both Udemy and Coursera often come up in conversations about the best learning platforms. A given person might assume they offer a similar experience […]
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The key difference between routers and switches in TCP/IP networks is that Switches primarily function to provide Layer 2 connectivity and Routers provide Layer 3 connectivity (as described in the OSI layer model). What exactly does this mean? From a high level view it means that switches allow hosts to communicate as long as they […]
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