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WAN Compression for FTP

We are running a MPLS network with 7 sites and a centralized Call Manager in our HQ. What is the recommended way to setup compression for FTP and/or other apps on our WAN routers (Cisco 2821's, 12.4.x). Will the compression affect the voice? Each site has 3MB circuits

Hall of Fame Super Silver

Re: WAN Compression for FTP


On a 3 MB circuit I would not think it was worth attempting compression. The overhead of compressing and decompressing has more benefit on lower speed circuits. But as the speed of the circuit increases you get less and less benefit from compression. It seems to me that 3 MB is beyond the threshold where it is worth it.



Re: WAN Compression for FTP


Does that include WAAS? I have'nt had a chance to play with it yet.

Hall of Fame Super Silver

Re: WAN Compression for FTP


I have not had much opportunity to work with WAAS either. My answer was mostly in terms of traditional compression. My impression is that most of what WAAS is doing is cacheing to reduce the amount of data transmitted rather than really compressing what is transmitted. So I would think that the law of diminishing returns would not apply so much to WAAS as it does to traditional compression.



Super Bronze

Re: WAN Compression for FTP

"Will the compression affect the voice?" It might if the voice is also compressed introducing enough additional latency or jitter or if other traffic compression imposes enough additional load on the router that also introduces enough additional latency, jitter or VoIP packet loss that goes beyond VoIP requirements.

Re: WAN Compression for FTP


If you are planning to implement application acceleration (i.e. WAAS, RiverBed, or iShaper) I suggest you POC them on the application you are trying to accelerate, I've seen many people having problem on the application acceleration device that they implement this is because some of their product selection decision making is enfluenced by their company direction (know what I mean).

I did POC them (with their respective engineers) and see what one can't do (and even make it worst) but the other can do better many times.