What is the MED? The MED (Multi-Exit Discriminator) is an optional BGP attribute, that is used when there are multiple external points for a single AS. For example, you may want traffic coming into your AS destined for network A to take one path but traffic destined for network B

The European Telecommunications Standards Institute (ETSI), have just released issue #1 of their new magazine. For those of you who may not have heard of ETSI, they are an independent, not-for-profit, standardization organization in the telecommunications industry. This includes standards such as the NFV MANO framework. For those of you

What is a BGP Peer Group? BGP peer groups are used to simplify configuration and to improve performance. This is achieved by assigning the same outbound policy to each of the neighbours. Because UPDATEs are generated only once per peer group rather multiple times for each neighbouring router, peer groups

TL;DR A path attribute is an additional piece of information associated with a prefix, included within the UPDATE packet during route exchange. Path attribute types include: Well-known - Must be recognized by all BGP implementation Mandatory ALWAYS be included within BGP UPDATE. Discretionary MUST be recognized by ALL implementations.

Introduction Within this article, we will look at the history of spine and leaf. We will first look at the problems seen with traditional networks, the background to the spine and leaf architectures aka Clos, and then finally look at how this fits into the spine and leaf architectures of

Introduction Within this article, we will detail the steps required to build a simple networking topology in Neutron 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

Introduction PIM (Protocol Independent Multicast) is a multicast routing protocol, that is used to send traffic from a single source to multiple destinations across a network. PIM is a collection of three protocols - PIM Sparse Mode, PIM Dense Mode and PIM Bi-directional .  PIM is termed protocol-independent because PIM does

Introduction Today, we will be walking you through the steps required to build an OpenStack Lab using Kolla-Ansible, based on the queens release. So what is Kolla-Ansible? In short, Kolla-Ansible is a highly customizable OpenStack project that is used to deploy OpenStack services and infrastructure components in Docker containers. Once

TL;DR BFD (Bi-Directional Forwarding Detection) is a highly efficient keepalive mechanism for routing protocols, that can detect link failures in milliseconds. Background As stated at http://brbccie.blogspot.com/, All routing protocols have some way of detecting failure, usually timer-related. Tuning the timers can theoretically get you sub-second failure