Category Archives: Networking & SDN

NFV Overview

Networking & SDN,

Network function Virtualization(NFV) refers to Services running on commodity hardware(compute, storage, network) which replaces functions that are done in specialized boxes currently. This applies mainly to Telecom sector, but the same concept can be extended into other areas as well. If we look at current products in the Telecom sector, there are separate hardware systems for each functionality. Examples of these systems are CPE switches, BRAS, LTE, mobile backhaul, firewall, load balancer etc. In all these systems, there is a tight coupling between the software stack and the hardware supplied. This causes multiple issues to the carrier/operator like high capital cost, multiple management systems, dependency on few select vendors etc. In the initial days, one of the reasons for using specialized hardware was that general purpose servers did not have enough horsepower. Newer generation servers pack in a lot of horse power that allows both control and data plane functionality to be done with commodity servers. This in addition to the maturity of Virtualization technologies(compute, storage and network) have made NFV more practically possible now. There will still be some scenarios where it is necessary to use hardware systems with  ASICs for high throughput and distributed processing needs etc.

In this blog, I will cover the following:

  • NFV Overview
  • NFV architecture Components
  • Use cases
  • Standards and Opensource components
  • NFV in relation to SDN and white box switches
  • Comparison to data center application
  • Challenges

In the next blog, I will cover popular NFV implementations available in the market today.

Continue reading NFV Overview →

Netconf and Yang

DevOps & Automation, Networking & SDN, , , , ,

Cisco’s acquisition of Tail-f prompted me to look deeper into what Tail-f does. That in-turn made me dig deeper into Netconf and Yang. Netconf is a device configuration and management protocol and Yang is a modeling language that’s used by Netconf. Yang modeling can also be used outside Netconf’s context. From looking at the history behind Netconf and Yang, I realized that Network management as a whole was a widely ignored topic for quite sometime. The current Network management techniques used by Operators seems to be very arcane and the recent SDN wave has triggered a renewed interest in simplifying Network management. In this blog, I will cover the following:

  • Shortcomings of SNMP.
  • Netconf and Yang overview with examples.
  • Comparison with Ovsdb and Openflow.
  • Opendaylight’s use of Yang model
  • Tail-f  NCS system’s use of Netconf and Yang.

Continue reading Netconf and Yang →

Cloud policy – Congress and Opflex

Cloud Platforms, Networking & SDN, , , , , ,

Recently, I saw a lot of press on Cisco’s Opflex protocol that allows a declarative policy model to control a physical or virtual device. There were discussions around if the Opflex protocol would replace Ovsdb and Openflow. Within Openstack, there is a new project called Congress that allows for creating a policy framework within Openstack. This blog is my attempt to get into more details on Congress and Opflex and explain the relationship between them. This is mostly information gathered from different references that I have listed in the end.

Congress:

Congress is a new Openstack project that is used to enforce compliance within the cloud environment. The end goal would be to integrate Congress with other cloud orchestration software as well. Compliance could be needed because of Government regulations, contracts between organizations, SLA enforcement etc. Following picture illustrates the need for Congress.

Continue reading Cloud policy – Congress and Opflex →

White box switches – Overview and current models

Networking & SDN, , , ,

In this blog, I will cover the basics of White box switches, current software models in White box switches, architecture overview of popular White box vendors(Cumulus, Big Switch, Pica8), popular Opensource projects related to White box switches and some final thoughts on the future direction.

In the current Networking switches, hardware and software are tightly coupled and it is not possible to change the software from 1 vendor to another keeping the hardware as same. This is different from Server space where hardware and software are decoupled completely.

The term White box Switch refers to a Networking Switch where hardware and software are loosely coupled and it is possible to change 1 of them keeping the other as same.

Following are some of the advantages of White box switches.

  • Multiple choices and no vertical lock-in to a single vendor.
  • Can increase speed of innovation.
  • Can reduce capex and opex.

Following are 3 models that seems to be emerging among White box switches.

Continue reading White box switches – Overview and current models →

Hybrid Cloud

Cloud Platforms, Networking & SDN, Storage & Virtualization, , , , , , ,

In the recent Rightscale survey, 74% of the respondents mentioned that they have a multi-cloud strategy and 48% of the respondents are planning for hybrid clouds. The recent trend in Cloud computing after Public and Private cloud is Hybrid cloud. Hybrid cloud offers the best of Private and Public cloud in some scenarios and Enterprises seem to like that.

In this blog, I will cover the following:

  • What is Hybrid cloud and Multi-cloud?
  • Use cases for Hybrid cloud.
  • Components of Hybrid cloud and design considerations – Cloud management, Network connectivity, Application portability
  • Popular Hybrid cloud providers – Rightscale and AWS, Vmware VCHS, Cisco Intercloud, Rackspace hybrid cloud, Redhat open hybrid cloud

Continue reading Hybrid Cloud →

Network Virtualization – Openstack+ODL integration

Cloud Platforms, Networking & SDN, Storage & Virtualization, , ,

In my previous blog, I covered basics of Network Virtualization and overview of commercial solutions available today. The most popular Open source Network Virtualization solution available today is Opendaylight. With the hydrogen release of ODL, ODL can be downloaded in 3 flavors: Base edition, Network Virtualization edition and Service provider edition. Network Virtualization edition adds components like Ovsdb, Opendove, VTN as well as Openstack integration. Ovsdb, Opendove and VTN are different approaches to provide multi-tenant networks. Ovsdb team has put in a nice set of hands-on tutorials for folks wanting to try out Openstack+ODL. I recently tried this out and I was very impressed. In this blog, I will cover my experiences in trying out hands-on Openstack+ODL integration.

Continue reading Network Virtualization – Openstack+ODL integration →

Network Virtualization – Overview and popular commercial solutions

Networking & SDN, Storage & Virtualization, , ,

In this blog, I will cover the following:

  • Overview and need for Network Virtualization
  • Relation between Cloud management and Network Virtualization
  • Network Virtualization approaches
  • Overlay Networks
  • Service chaining
  • Popular Network Virtualization solutions – Vmware NSX, Juniper Opencontrail, Cisco ACI.

Overview and need for Network Virtualization

Network Virtualization allows for abstracting the Networking resources into a logical/software model so that the same set of physical resources can be shared by multiple tenants in a secure and isolated manner. There are 2 kinds of Networking resources, one is the physical resources like Router, Switch and another is appliances like Firewall, Load balancer etc. The appliance can be either physical or virtual. NFV(Network functions virtualization) can be considered a subset of Network Virtualization.

Network Virtualization is similar to Server Virtualization. In server virtualization, compute resources are virtualized, while in network virtualization, networking resources are virtualized. Network virtualization took much longer time to come to the market compared to server virtualization. Following picture gives a good comparison between the 2.

Continue reading Network Virtualization – Overview and popular commercial solutions →

Cloud Infrastructure

Cloud Platforms, Networking & SDN, Storage & Virtualization, , , ,

In this blog, I will cover:

  • Major components of the Cloud infrastructure from hardware perspective
  • 2 models of deploying Cloud infrastructure
  • Overview of different converged infrastructure players and their solutions.
  • Deepdive into VCE converged infrastructure solution.

Major Cloud hardware components are Compute, Storage and Network. There are 2 models of building Cloud infrastructure.

  1. Build using discrete components.
  2. Buy turnkey solution called as Converged Infrastructure.

Continue reading Cloud Infrastructure →

Openflow history and some hands-on

Networking & SDN

In this blog, I will cover the evolution of Openflow(from 1.0-1.4). Also, I will cover the hands-on stuff that I tried with Openflow.

Openflow is a protocol by which we can control a Switch’s data plane with the Switch exposing flow tables as mentioned in Openflow protocol. Flow tables provide an abstraction and It is not necessary to expose internals of the switch.

Continue reading Openflow history and some hands-on →