We were discussing Riverbed Operating System (RiOS) technical concepts. For Data Deduplication, RiOS intercepts and analyzes TCP traffic, segmenting the data and indexing it. It replaces duplicate segments with proprietary hierarchical references that save massive amounts of data.The segments are compressed using a Lempel-Ziv based algorithm that achieves good peak compression ratios. The size of the segments stored on disk is approximately 100 bytes allowing detection of fine grained changes in the traffic. Since the comparison is at byte level, the same works for both encrypted as well as unencrypted traffic. This scalable data reduction (SDR) technique can be performed interchangeably on disk or in memory. It can be done adaptively as well in either location or both. The best fit for particular connections or overall workload determines the strategy. Since disk accesses are involved, the appliances are fitted with solid state disks for better performance.
It is important to note that segments are byte chunks and agnostic of the metadata on the corresponding data transfer. Filenames, e-mails, objects or anything that the segment belongs to does not affect are not recognized. This is both a convenience as well as a limitation.  The convenience is that the changes are detected even if they are fine grained and applied consistently regardless of file renaming, object cloning or email replies. The limitation is that an application protocol could have been added that tags the traffic with metadata based on time or space for more information to the SDR. In any case, the SDR has to work across all TCP traffic and therefore differs from cache based solutions that cannot recognize the data as the same when tracking file or object based entities.
RiOS overcomes the chattiness of transport protocols through transport streamlining which is  set of techniques that reduce the number of round trips necessary to transport information across the WAN while maintaining the reliability and resiliency of the transport.The techniques involve window scaling, intelligent repacking of payloads, connection management and other protocol optimization techniques. These are standard techniques and therefore RiOS remains true to the fundamentals such as congestion control, error detection, connection management for good neighbor etc without adding extra requirements such as the use of a tunnel, proprietary protocols or other non-standard protocol optimization techniques. Consequently this native transport streamlining design avoids the issues such as traffic mixing, MTU sizes or TCP over TCP that affect alternative designs based on tunnels etc.

#codingexercise
Double  GetNthRootSumOddRaisedPMinusQAndEvenRaisedPPlusQ (Double [] A,Double  p, Double q)

{

If ( A== null) return 0;

Return A.NthRootSumOddRaisedPMinusQAndEvenRaisedPPlusQ(p, q);

}