DRE Question

johng231 · ‎08-25-2011

Hello

Does the WAAS maintain a peer to peer dre storage relationship? Say branch "A" downloads a powerpoint file and then branch "B" downloads the exact same file, does your core WAAS keep multiple copies for each separate peer?

Bhavin Yadav · ‎08-25-2011

Hi John,

Each WAE has a single DRE database, but this database is provisioned into "contexts", where each "context" is a partition of the DRE database dedicated to a specific peer. In this way, each peer WAE will be allocated an amount of storage capacity within the local WAE DRE database.

Hope this answers your question.

Regards.

PS: Please mark this as Answered, if this answers your question.

johng231 · ‎08-26-2011

Thanks for your response Bhavin. Let me make sure that I'm clear on this. So each context can essentially have copies of the exact same files? If this is true, are there any plans in the future to move towards a universal DRE database?

Bhavin Yadav · ‎08-26-2011

Hi John,

Asnwers for you:

So each context can essentially have copies of the exact same files? Not sure if I understood your question correctly but each WAE has a single / separate partition in which they store contexts for that WAE DRE cache. So, if different WAE requests same file from different site, it will be in "that" particular WAE's DRE partition.

If this is true, are there any plans in the future to move towards a universal DRE database? Not sure why you are looking for universal DRE partition. Universal cache architectures increase the risk of disrupted application

performance. Universal cache architectures, designed with the objective of maximizing overall storage capacity, store a single instance of each cached object for all branches. The resulting risk, if the only instance cached object is lost – either through data eviction due to cache refresh, or from traffic bursts – then the IT benefits of WAN optimization are lost until the evicted objects are re-cached. There are few more reasons why the universal DRE partition is not preferred.

Also I can't answer if there are any plans to comeup with universal DRE parition. The best person to put this question across is your Cisco Partner / Account team. They have good idea of up-coming road map. If this is not in the road map, you can ask them to add an enhancement / new feature across product management team to have it available in the future versions.

Hope this helps.

Regards.

PS: Please mark this as Answered, if this answers your question.