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Introduction Within this article we will detail the steps required to build a simple Neutron networking topology using the OpenStack CLI. Topology Our topology (Figure 1) will consist of an L3 router, an external network, a tenant network and a range of floating IPs. Our external network will be a VLAN based network and … Read more
The other day I asked myself, What is the difference between apt-get update and apt-get upgrade? As I’m sure many other people, at some point may ask the same, I thought I would share the answer. Quite simply, apt-get update – updates the list of available packages, and their versions. However it does NOT upgrade … Read more
OpenDaylight is an SDN controller provided by the Linux Foundation. In this article we will show you the steps required to perform a simple installation upon Ubuntu. Install Binaries box@odl:~$ sudo apt-get update box@odl:~$ sudo apt-get install software-properties-common box@odl:~$ sudo apt-get install maven git unzip Install Java 1.8 {loadposition content_lock} box@odl:~$ sudo add-apt-repository ppa:webupd8team/java box@odl:~$ … Read more
What is OpenFlow? OpenFlow is a protocol, released by the ONF that allows the remote modification of a network switch’s forwarding table. In other words, the control plane is decoupled from the forwarding plane, enabling network controllers to define the flow of traffic between switches far greater than standard routing or forwarding protocols. Figure 1. … Read more
What is SNI? SNI (Server Name Indication) is an extension to the TLS protocol, that provides the ability to host multiple HTTPS-enabled sites on a single IP. How does it work? Prior to SNI the client (i.e browser) would send the requested hostname to the webserver within the HTTPS payload (Figure 1). Due to the … Read more
Introduction First of all, what is a route leak? A route leak is the propagation of routing announcement(s) beyond their intended scope – RFC7908 Within this article we will look at 2 methods of route leaking within an MPLS environment – static routes and route maps. To demonstrate both methods we will look at 2 … Read more
Introduction Within this article we will walk through the various steps required in configuring MPLS. NOTE This article does not look to explain the various terms and concepts of MPLS, for details around these please see Getting to Know MPLS. Overview Within our example we will have 2 customers COSTA and STARBUCKS. Each customer consisting … Read more
Introduction Cisco Express Forwarding (CEF) is a packet-switching technique used within Cisco routers. The main purpose of CEF is to optimize the forwarding of packets and increase the packet switching speed. History Prior to CEF there were 2 methods for packet-switching – Process- Switching and Fast-Switching. Process-Switching The first method, process-switching is the oldest and … Read more
Introduction Even bad code can function. But if code isn’t clean, it can bring a development organization to its knees. Every year, countless hours and significant resources are lost because of poorly written code[1]. Within this article we will take the key concepts, and points around writing Clean Code – referenced from the amazing book, The … Read more