Neighbor Discovery Protocol in IPv6 – An Introduction

Neighbor Discovery Protocol in IPv6 is similar to Address Resolution Protocol (ARP) in IPv4. The main purpose of both the protocols is to enable a host (node) to determine the link layer addresses (MAC addresses) of the nodes it wants to communicate with in the local network, and to find out the link layer address of the router though which it can access a node in an external network, so that the actual exchange of messages can happen between the two nodes.

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VRRP – Virtual Router Redundancy Protocol provides Network failover/redundancy

VRRP (Virtual Router Redundancy Protocol) provides fail-over/ redundancy for critical gateway network components like Routers, L3 Switches, Firewalls/UTM’s, etc. VRRP eliminates single point of failure at the gateway level and in certain network configurations, it can even provide load balancing along with fail-over. Let us learn more about VRRP, in this article.

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What is: ARP (Address Resolution Protocol), ARP Cache Table, ARP Poisoning/ Broadcast Storm

In this article, let us first look at an example of what happens when two computers – CP1 & CP2 try to communicate with each other and through this example, understand what is ARP (Address Resolution Protocol) & ARP Cache Table and why they are required. We will also discuss shortly about ARP poisoning and ARP broadcast storm. Its important to understand ARP to successfully troubleshoot a network.

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You should know about a new and upcoming Networking protocol called Openflow

What are the current challenges in a network? Scalability? Disparate and multi-vendor overlay networks? Long time required for re-configuring the global network parameters? Inflexibility? Distributed control and management planes? Openflow is a new and upcoming networking protocol that might just take networking in a new direction altogether by allowing an external controller to control forwarding decisions of a group of switches / network devices. So, the intelligence that gets built into each network switch might get centralized in the future!

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NTP – Network Time Protocol

Network Time Protocol is used to synchronize the time between various devices (clients) in a network as more applications (like precision manufacturing, real time – data, voice) depend on accurate time stamping by multiple systems to function. In this article, let us try to understand the Network Time Protocol better.…

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