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How Does Route Selection Work in Cisco Routers?


Most routing protocols have metric structures and algorithms that are not compatible with other protocols. In a network where multiple routing protocols are present, the exchange of route information and the capability to select the best path across the multiple protocols are critical.

Administrative distance is the feature used by routers to select the best path when there are two or more different routes to the same destination from different routing protocols. Administrative distance defines the reliability of a routing protocol. Each routing protocol is prioritized in order of most to least reliable (believable) using an administrative distance value.


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How to Configure EtherChannel Easily? - A Demonstration

What is EtherChannel

Ethernet is a LAN technology based on the Institute of Electrical and Electronics Engineers (IEEE) 802.3 standard. Ethernet is a shared medium between the networking devices and provides the specific bandwidth to the end users. Ethernet also evolves as the users and their need of accessing the resources increases.  

Ethernet Generation

The evolution helps end-users’ effective access to resources, both on- and off- the campus network. However, today's mission-critical applications and services demand networks that provide high availability and reliability. This article will focus on the technology that you can use in your network to provide higher bandwidth and reliability between switches.

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New Cisco CCNA Cyber Ops : Are You Ready for Security Analysis ?

SOC thumb

In the intensely competitive environment, startups and agile firms are overturning incumbents with digital business models, products, and services. In the 'Digital Era', we are observing the exponential growth in the data over internet. Simultaneously, organizations are facing mounting challenges from cybercrime, cyber-espionage, insider threats, and advanced persistent threats (APT).

As per the Verizon 2015 Data Breach Investigation Report (DBIR), 60 percent of businesses being breached happened within minutes or less and half of these incidents took anywhere from months to even years before being uncovered. We safely can derive inference that breaches tend to happen very quickly and on average take a long time to be detected by the targeted organization. These organizations can be divide into two types: 1) those who have been hacked, and 2) those who don’t yet know that they have been hacked.

Even after the tremendous efforts by the IT security vendors, the below questions still exist:

  1. Aren’t governments and big businesses investing significant amounts of money already into developing countermeasures to cyberattacks?
  2. Why are existing security products unable to stop these threats?

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Journey from Legacy to Next Generation Firewalls - NGFW

Corporate networks are encountering the highest levels of change in the recent history. Users require anywhere, anytime access to the network from a variety of company-owned and personal mobile devices. In addition, software applications have evolved to be highly dynamic and multi-faceted, blurring the line between business applications and personal ones that may increase the company's exposure to Internet-based threats. 

As a result, most organizations are facing difficulty in achieving an optimum balance between the productivity gains and the security implications poised by the productivity tools & apps.

Security Balance

The scenario warrants that the smarter organizations must adopt a new approach of IT security that unifies the network's streamlined security operations, without abandoning any time-tested method such as Secure Sockets Layer (SSL), Anti-Viruses, Intrusion-Prevention Systems (IPS), Virtual Private Networks (VPN), and firewalls, etc.

Firewalls have been a first line of defense in network security for over 25 years. They establish a barrier between secured and controlled internal networks that can be trusted, and untrusted outside networks such as the Internet.

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How Does Address Resolution Protocol (ARP) Work? - A Demonstration

Everyone who is in the networking field, knows about Address Resolution Protocol (ARP).

In the beginning of my IT career, when I started to study the networking, I struggled to understand and remember the definition of ARP.   I had some questions frequently arising in my mind, e.g.,

  • What is ARP exactly?
  • How does it work?
  • How to test it's working?
  • What is the easy way to remember it?

Here I take this opportunity to present you a good explanation of ARP and how it works.

What is ARP?

Address Resolution Protocol (ARP) is a protocol used by the Internet Protocol (IP) [RFC826], specifically IPv4, to map IP network addresses to the hardware addresses (MAC Address) used by a data link protocol.

This definition of ARP has 2-main aspects:

  1. Used by Internet Protocol (IP)
  2. To map IP network address (IP Address) to hardware address (MAC Address)

We will explore these two main aspects of ARP  with the help of following topology which consists of 1-Hub and 3-PCs. 

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How Did Cisco Save Me from Cyber Security Nightmares?

I am Mr. Secure and run a business company. I used to feel secure due to having the basic security for data, network, and devices of my infrastructure. I believed that --

"No one will be interested in attacking on our data, network, and devices. So I need not to not worry about the security much and -- Why to waste a lot of money on securing all these? I am making money. My team is performing fantastically. My business growing."

"…. Why to make fuss about security? After all I have so many other more important things to do."

One fine day recently…. I, my team, and all the clients were not able to access our company website. We soon found that our network was breached, and our website had been hacked. All the important & confidential data of the company, website, and its users was in the hands of attackers (read, Hackers). This turned out to be a classic case of ransom, as they now wanted me to pay them _____ a certain amount of money, I was communicated that they, otherwise, would reveal or sell the data to my competitors. This left me with no choice, but to pay the money to attackers. So I had to pay the money to them and then I was granted back access to my own website & data.

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Ethernet Roadmap 2016 - All Graphics

Recently, the IEEE 802.3 committee published the 2016 version of the Ethernet Roadmap that highlights the slow progress of new Ethernet standards. It good to get some visibility here so that it can be included in your own design strategy.

The 2016 Ethernet Roadmap shows the latest developments in Ethernet and contains historical information as well as estimates for when future speeds may become available. The roadmap shows new technologies such as Flexible Ethernet (FlexE), new optical modules and 4-Pair PoE. Ethernet nomenclature is also explained and the Ethernet Ecosystem of consumer, residential, enterprise, campus, hyper-scale data center and service providers is revealed. The map is beautifully drawn and packed full of information.

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How to Integrate GNS3 With VMWare Workstation Easily?

Intergration of GNS3 with VMWare

Objectives Of 15-Steps Visual Guide

The ultimate guide to understand the nuances of integrating GNS3 with VMWare WorkStation version 10/11/12. Two approaches of this integration has been elaborated & presented in this visual guide.

The idea is to provide the helping tool to candidates aspiring to practice and obtain their CCIE, CCNP, CCNA certifications.


We will create and configure the above topology. For that we need, two routers (ISP-India, ISP-US), two hosts (, Client), and two Virtual Networks: 

  1. LuminisIndia will use this network
  2. Client will use this network 

We will achieve the fully working topology as shown above, by following the steps in this Visual Guide created by: Meena, Sr. Manager IT and Consultant. So let's start.

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