Protocols
TACACS+ – Control and Monitor Access to Network Devices using this AAA Protocol
TACACS+ is a AAA Protocol (Authentication Authorization and Accounting Protocol) that allows secure user access to network devices by controlling who can access the device and what they are allowed to do, once they access it. Like RADIUS, AAA services are centralized (using a TACACS+ Server) and TACACS+ can even maintain individual command logs.... »
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... »
What are: Network Ports, TCP & UDP
Network Ports: When one computing device wants to communicate with a remote computing device, it needs two important parameters to reach and communicate with it. First, it needs the IP address of the remote computing device so that it can locate it over WAN / Internet, and it also needs to know the specific... »
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. »
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... »
DHCP – Dynamic Host Control Protocol
DHCP refers to Dynamic Host Control Protocol. DHCP is responsible for dynamically assigning IP addresses to all the computers in a network immediately after the computer starts. Lets learn something more about DHCP, in this article. »
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... »
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. What is the Network... »
A Conceptual Introduction to Static Routing, RIP & OSPF
In large networks, Layer-3 Switches/ Routers are important and inevitable. They help contain the broadcast domain by sub-dividing the network in to various segments. But once a network is segmented, you need to route packets between the various sub-networks. Routing protocols / methodologies like Static Routing, RIP (Routing Information Protocol) & OSPF (Open Shortest... »
BGP – Border Gateway Protocol Simplified
In this article, we will have a look at BGP - Border Gateway Protocol, a routing protocol that made the Internet possible! We will also have a look at IBGP (Internal BGP) which can be used for routing in very large companies and hence helps them scale their networks. »
