Applications Notes

• Why Plan Network Synchronisation?
• What is a Sync Plan?
• Why Write a Sync Plan?
• How to Write a Sync Plan?
• Our Planning Methodology

Why PlanNetwork Synchronisation

• Synchronisation is just a support utility for all Time Division Multiplexed (TDM) networks.
• The Quality of Service (QoS) of any network is directly related to the quality of network synchronisation.
• Synchronisation units are not cheap and do not directly generate revenue. Investment in synchronisation equipment does not guarantee good synchronisation.
• 95% of all synchronisation functionality in any TDM network lies in the traffic elements.
• Synchronisation investment is wasted without careful deployment and therefore careful planning.
  

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What is a Sync Plan?

A Sync Plan is usually a document or network representation and should describe:

• The techniques employed in the network to distribute synchronisation.
• Any limitations imposed by the behaviour of the network elements.
• Any assumptions made by the author.
• As far as possible, a description of the sync configuration of every sync transporting element.
• Predicted single points of failure.
  

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Why Write a Sync Plan?

Synchronisation is a hidden network of distribution paths, usually overlaying, to some extent, your core transmission network. It is effectively invisible.
Your Sync Plan has three distinct purposes:

• It should be used at implementation (or re-implementation) as the configuration instructions for the sync plane of every element in the sync network.
• It should be used throughout the operation of the network to allow Network Operations to make informed decisions when changing the configuration of the network.
• It should provide enough information to enable root cause analysis to be performed in the event of a sync failure.
  

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How to Write a Sync Plan?

There is no single, correct way to synchronise a network, there are only shades of good & bad.
“Surely there must be a software tool which will automatically design my Sync Plan for me?”…
…unfortunately not.

With today’s multi-vendor, multi-technology networks the task is just too complex.
The Sync Planner is still required.

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Our Planning Methodology

Our planning methodology is based upon six simple directives:

1. My Sync Plan should ensure that all network elements have a sync source traceable to G.811 during steady state network conditions.
2. As far as possible, my Sync Plan should ensure the distribution of suitable clocking signals to each and every piece of network equipment requiring synchronisation during any single network failure condition.
3. My Sync Plan should identify the optimum investment in synchronisation equipment.
4. My Sync Plan should be as simple as possible to understand, implement and maintain.
5. My Sync Plan should be comprehensively documented to suit the purposes of those who need it use.
6. My Sync Plan should be regularly re-evaluated.