Natalie Timms

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Where the Cloud Touches Down: Simplifying Data Center Infrastructure Management

Thursday, July 25, 2013
10:00 AM PT/1:00 PM ET

In most data centers, DCIM rests on a shaky foundation of manual record keeping and scattered documentation. OpManager replaces data center documentation with a single repository for data, QRCodes for asset tracking, accurate 3D mapping of asset locations, and a configuration management database (CMDB). In this webcast, sponsored by ManageEngine, you will see how a real-world datacenter mapping stored in racktables gets imported into OpManager, which then provides a 3D visualization of where assets actually are. You'll also see how the QR Code generator helps you make the link between real assets and the monitoring world, and how the layered CMDB provides a single point of view for all your configuration data.

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A Network Computing Webinar:
SDN First Steps

Thursday, August 8, 2013
11:00 AM PT / 2:00 PM ET

This webinar will help attendees understand the overall concept of SDN and its benefits, describe the different conceptual approaches to SDN, and examine the various technologies, both proprietary and open source, that are emerging. It will also help users decide whether SDN makes sense in their environment, and outline the first steps IT can take for testing SDN technologies.

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Securing The Software-Defined Network

With the emergence of software-defined networks (SDNs), security must become a core component of the network. Network security can no longer be an afterthought, or added with the assumption that it will "just work" on top of an existing network. With SDN, security services are pre-planned and become the foundation for connectivity. The benefits are centralized policy management, automated provisioning, and real-time mitigation. Sounds good, right?

The problem is the security perks you get from SDN are only as good as what you build into the system from the start. If any element or interaction in the SDN model can be compromised, the integrity of the whole network can be affected.

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Integrating Security And SDN Regardless of the architectural model or the controller-agent communication protocol you choose, SDNs provide perimeter security to an organization. Yes, networks still have a perimeter in terms of today's threat landscape. The perimeter, however, is no longer a single boundary or device dividing outside from inside.

The whole concept of the Internet of everything, where any IP-based device connected to a network may pose a threat, requires each network element or function within an organization be secured in its own right. SDNs address this issue, because agents and controllers can be provisioned to provide perimeters to individual devices or services.

Security services integrated into agent systems such as identity management, threat defense, and content inspection, as well as those that impose compliance and regulatory requirements, can be applied to connections and flows. Attacks and anomalies are reported to controllers, which then enforce network-wide containment and distribute protection updates.

[Want to see the major SDN models from top vendors, in living color? Check out our slideshow on "10 Software-Defined Networking Architectures."]

Once deployed, security policy provisioning, problem resolution, and performance monitoring becomes centralized and automated.

Security Requirements For SDN

SDN can provision and enforce a security strategy, but the success of this strategy depends on how well the SDN itself is protected. A SDN consists of a number of layers and interactions, each requiring its own protection.

Deploying SDN also introduces new potential threats and vulnerabilities, as well as putting a different spin on some old favorites. The best example is a simple denial of service (DoS) attack. In a traditional network, an attacker typically targets one or more devices by overwhelming the CPU. This limits control plane services on each victim device, and can send traffic down a black hole if alternate forwarding paths are not available.

To execute a very successful DoS attack on an SDN, an attacker can simply target one agent device in the network by injecting false flows. This bogus information is then easily distributed to multiple SDN agents. It can overwhelm the controller CPU and quickly lead to the propagation of invalid flow information on all agents serviced by the controller.

The following table summarizes security requirements for the key components of an SDN:


Security Mechanisms

Controller-specific hardening

Secure management protocols; AAA; OS patches; enable only used services, ports, and protocols

Device hardening for agents and controllers

Control plane, management plane and data plane security mechanisms; physical and Layer 2 security

Network services

Disable unused ports, protocols and services; infrastructure access lists; and firewall protection


Secure coding practices; digital signing of code; integrity checks


Role-based access control; encryption; logging; change management processes

Communications channels

Authentication and authorization; encryption

Agent security services

Firewalls; identity; threat mitigation

SDNs provide an opportunity to make security the focal point of a network solution, rather than an add-on. Many existing, proven security mechanisms can be implemented and more easily provisioned and monitored using SDN. As new threats are detected or regulatory policies are required, enforcement can be simplified and streamlined. To be most successful, however, the network architects must understand the components of SDN and ensure each has its own protection.

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