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For many years, I have advised customers on how to optimize their enterprise networks to support rich media communications, and as a result, there are few best best practices I would like to share in this article.

First, let me define what media ready networks are. Its the ability of the corporate IT network to efficiently handle Interactive voice and video and streaming traffic delivering flawless user experience irrespective of their device type and network location.

So how do we go about analyzing the network which spans hundreds of network elements (routers, switches, wireless access points, firewalls)? Of course, we cannot assess each and every node as this would be labor intensive and in most cases not necessary. Below is a simple framework which helps to narrow down the scope of assessment based on few criteria’s.

As an example, the outcome of the scoping effort would be something like 2 data centers, 1 campus and 10 branches, Immersive and desktop traffic profile, so on and so forth…

Once you narrow down the scope using the above framework and determined the network elements , its time to assess these elements across five compliance modules. These modules are listed in the order of importance.

1. Quality of Service: Assuming that you have well defined enterprise wide Quality of Service (QoS) strategy, ensure that the Identification, classification and queuing techniques are implemented at LAN and WAN devices for voice and video traffic. If you are using an MPLS service provider, make sure your QoS markings for voice and video aligns with the SP so the real-time traffic can get priority treatment within the SP cloud.
2. Service Level Agreement (SLA): Ensure that the SLA between the representative sites are within the recommended thresholds. For example, thresholds of 150ms one-way latency, less than 50 ms of jitter and .05% packet loss is recommended for video. If you have deployed Cisco routers at the representative sites, you can use IPSLA feature within the IOS feature-set to measure the SLA parameters. Most of the networking vendors offers this as professional services if IPSLA is not an option.
3. Hierarchy and Modularity: In this compliance module, we look at some design best practices. An hierarchical and modular network design (versus full mesh, partial mesh or ring topology) provide better network convergence and policy implementation. Here we also ensure that all modules at a given level share the common functionality.
4. Hardware and Software: Here we assess for any end of life hardware or software which could potentially affect user experience. For instance, certain switches share a common ASIC for group of common ports. So if you are connecting an immersive video system to one of these ports, make sure that the remaining ports within the group is unused so that the ASIC is dedicated to this immersive video system giving it complete access to the switch backplane.
5. Security: Finally from the security standpoint, make sure that the firewalls (if any) along the path of the media traffic allows RTP/SRTP and SIP TLS communications between the endpoints, call control and conferencing applications.

I have kept this at a high-level as a guide but if you have further questions after reading this article, please post them below.