As compression technologies broaden, savings grow

Compression devices have been around for years, but in their latest incarnations they use more than just compression to pack extra data onto fixed-size WAN links. At least that’s the conclusion of our Special Focus story this week which takes a look at the evolving data compression market.

Our author (tgreene@nww.com) says vendors come at compression from different angles. Some, like Expand, started out doing traditional compression – replacing patterns with smaller patterns so less traffic crosses the link. Others, like Orbital Data, use the fact that transfer control protocol (TCP) throttles back traffic when faced with delay, then builds it back up to speed very slowly – too slowly – when the perceived congestion clears.

Others like Riverbed look at applications themselves and spoof predictable back and forth locally in the appliance rather than have the full conversation cross the WAN. Others shape traffic to give higher priority to key applications that are optimum WAN speeds. And still others use more than one technique and claim effective throughput improvements of 90% or more depending on the type of data.

Since the different vendors use different algorithms and technologies, figuring out the impact of any given vendors’ gear is key. So the type of compression gear that will work best is unpredictable. So he recommends something that not many customers have done to date: try out boxes that use different technologies to find out which one make the most significant improvements for a particular network.

Our story looks at a number of user case scenarios and the savings many of these folks are enjoying. For more see: https://www.nwfusion.com/news/2004/091304specialfocus.html