Compression/Caching

Increase WAN Capacity for Application Traffic:

Packeteer's application-intelligent compression technologies deliver an easy way to quickly increase WAN capacity over the same physical links, improving application performance and user response times. Packeteer's unique PacketShaper architecture enables continuous improvement in compression gains—while ActiveTunnel simplifies compression setup and configuration between two PacketShapers.

Compression with control means that the added capacity from virtual bandwidth goes to your applications with the highest priority.

Application-intelligent Symmetric Compression:

Compression works between two PacketShapers—symmetrically—to engage specialized, low-latency compression algorithms. Using multiple traffic compression techniques—including multiple algorithms, fragment caching, header compression and packet bundling—our Layer 7 Plus application intelligence helps identify different application types and apply the optimal compression techniques to each—or not at all.

Application-specific Selective Compression:

To optimize compression, set up separate dictionary caches or different applications—avoiding the dilution effect where large amounts of other traffic weaken compression effectiveness. PacketShaper also chooses a different compression approach for packet payload—instead of for packet headers—apply "two pass" compression to less latency-sensitive applications.

Sometimes choosing not to compress an application is as important as compressing it. Applications—like SSL, jpeg files, VoIP data payloads and already-compressed Citrix® traffic—don't generally benefit from compression and are not worth injecting even latency minimal amounts. When it makes sense, PacketShaper’s application intelligence opts not to compress, saving resources and getting better overall compression results.

Compression results vary, depending on application mix. Beware of promised 5:1 or even 10:1 compression ratios—which are based on best-case tests. A more realistic range is 2:1 to 3:1; however, 4:1 to 5:1 can be achieved if you have more compressible traffic types.

Plug-In Architecture:

Packeteer's plug-in architecture enables Packeteer to add new, application-specific compression algorithms over time. We continue to update our compression technologies—releasing four new algorithms since 2003 and improving effectiveness by about 40 percent. As plug-ins, new classifications can be easily downloaded as they become available—without waiting for a major software release.

Minimize Latency: MTU Management, Packing and Rate Control:

To minimize latency and further accelerate traffic, PacketShaper's MTU (maximum transmission unit) management automatically adjusts MTU size to eliminate excess delays from link serialization delay or increase MTU to eliminate overhead from headers and acknowledgements.

Selectively bundling or concatenating packets, PacketShaper evaluates packet and MTU size as well as network timing to determine if, and when, combining multiple compressed packets into a single larger packet makes sense. Packing reduces overhead and improves compression gains.

ActiveTunnel: Automatic Setup and Overload Protection:

Packeteer's ActiveTunnel feature automatically detects Xpress-enabled PacketShapers on the network and builds acceleration tunnels between them. Beyond enabling Xpress—a simple matter of toggling "on"—no configuration is required to set up or maintain the tunnels.

Since high traffic volume overloads compression efforts—actually increasing latency—PacketShaper automatically detects overloaded situations and backs off or steps up, as appropriate. Traffic shaping still takes precedence over compression when the network gets swamped.

Reduce Data - Optimize the WAN:

Packeteer iShared compression and caching technologies increase WAN capacity—with as much as 99 percent reduction in bandwidth—over the same physical links, improving performance and user response times while leaving room for other application traffic. Cut back on redundant and unnecessary data travel while making the most of bandwidth.

Compression:

TCP Flow Compression reduces data on the first pass through the infrastructure—compressing TCP flows as they move across the network the first time. Dictionary-based compression dramatically reduces WAN traffic all subsequent times a file is accessed.

Dictionary-based Compression

Dictionary-based compression dramatically reduces bandwidth use and accelerates performance.

Caching:

Caching holds data at the branch office in the remote appliance. Automatically and transparently ensure the best performance for frequently accessed data with the self-managing cache.

• File-aware Caching uses file differencing techniques to write, update and repeat access to those files—for a much faster response and better bandwidth use.
• Application-intelligent Caching for Microsoft Exchange attachments and static Web pages reduces the impact of attachments over the WAN—particularly valuable as up to 90 percent of Microsoft Exchange storage is in large e-mail attachments.

Infrequently accessed data expires out of a cache—making room for fresh data—while the authoritative file stays back at the data center in primary storage.