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A new Application recognition paradigm – Flow metadata (Part 2)

- June 19, 2012 - 0 Comments

In the first part of this blog we discussed how Flow Metadata addresses encrypted/obfuscated traffic, multi-stream interactions, ensures end-to-end  consistent policies and enables fine-grained policies. In this part of the blog, we discuss additional deployment scenarios making network classification a real challenge and how metadata addresses them.

Deployment Challenges

Typically, enterprises do not trust DSCP marking from general purpose computers such as laptops. When traffic arrives at the first hop switch, video desktop and softphone traffic often get remarked  to best effort resulting in sub-optimal quality. While traditional deep packet inspection can potentially solve this problem, switches do not typically have deep packet inspection capability and the traffic may be encrypted.  The flow metadata component allows applications using an out of band signal to convey information to the network. This allows appropriate policies to be applied to rich media applications while preserving enterprise security policies.

Operating systems can incorrectly reset DSCP values resulting in sub-optimal quality. This is a commonly found configuration problem in Windows 7 deployment. Flow Metadata allows an application to explicitly signal any arbitrary attributes to the network from node to node. This allows the DSCP value to reset to the correct value, improving the quality of experience.

In addition to enabling granular policies, Medianet Media Awareness creates new opportunities for end to end network policies that were too complex before. For example,  as enterprise data flows over Service Provider networks, it can lose its original QoS context and enterprise DSCP values. The problem can be further exacerbated by encryption. The flow metadata component allows applications to produce application context, and for  routers and switches to consume the information hop by hop. This ubiquity in sharing application context makes it possible to create and maintain granular policies end to end.

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