DMVPN

1. DMVPN DMVPN – Dynamic Multipoint VPN is a technology that uses IPSec, mGRE and NHRP to provide a dynamic VPN infrastructure. DMVPN evolved in several phases as follows: DMVPN phase 1: Hub and Spoke – spokes only communicate via Hub DMVPN phase 2: Hub and spoke with spoke to …

How CEF works

1. Process Switching 1.1 How it works Network interface detects a new packet on the wire. The interface will receive the packet and will place it in the I/O memory. It will then send a “receive interrupt” to the processor to indicate that a new packet needs to be switched. …

MPLS L3 VPN

This article assumes the “provider” network already has an IGP in place and that the LDP is configured to advertise label bindings …

IS-IS Mechanics – CLNP

1. ISO OSI Terminology ISO OSI term TCP/IP Equivalent End System Host Intermediate System Router Circuit Interface Area Area Domain Autonomous System …

IS-IS 101

1. Starting the routing process Starting IS-IS process requires a 2 step configuration: 1. In the global config 2. On the interfaces …

Cisco Enterprise Architecture

1. Hierarchical Model Cisco Enterprise Architecture is based on a hierarchical model that¬†consists of: Access Layer: provides connectivity without compromising network integrity …

IPSec VPN 101

1. IPSec IPSec is a framework of open standars that offers security services to IP communication. When using IPSec you get the …

Linux Terminal Colors

1. Enabling colored output 1.1 ls –color In Linux, you use the ls command to display the contents of a folder. ls …

Linux File System Hierarchy

Linux File System Hierarchy is a reference that describes how the Linux Files System Hierarchy should look like. Currently, the FHS in …

PfR 101 – Perfromance Routing

1. PfR Technology PfR stands for Performance Routing, but the feature was first called OER (Optimized Edge Routing). This is why most …