WAVE-274 Core Fan

[mlouis]

What is the core fan out ratio for the WAVE-274?

Can you explain how Cisco is determining the core fan out ratios and how they size a WAE for a particular environment based on DRE size?

Its my understanding that the DRE cache values in the DRE database for optimized chunks are unique to each peer. Meaning that the chunking is not shared across multiple peers. So if you have 10 sites optimizing the same file at each site, the main core site DRE cache would represent that file 10 times in its database as 10 different chunks differentiated by what peer it came from. Is that the case? If so, why wouldn't or couldn't you share that information in the main core site cache to reduce DRE disk space utilization?

[mchin345]

The 274/474 are not meant to be core devices. However, if it is a smaller deployment with only a few sites, or a POC, it should not be a problem.

No problem using a 274 on both ends of a link for a POC. As they are not meant to be a 'core' device. They aren't publishing fan-out numbers.

[ropethic]

Cache architectures are designed to accomplish one or both of the following:

1 Application Response time improvement

2. Bandwidth reduction

Cisco WAAS is designed to provide both but with an emphasis on application optimization. If bandwidth reduction is primary goal, then with a single file store serving multiple peers the potential is there to increase response times. Hence WAAS point-to-point peering.

In terms of fan out, the WAVEs are intended for branch deployment offering Windows core application offload.

They are recommended for for Central Manager function, 274 supports 125 devices, 474 250, and 574 500