HTTP and HTTPS

Traffic that flows over the World Wide Web contains content that is increasingly dynamic, contains a greater percentage of rich data types, and is often encrypted and travels over secure connections. Passing image, videos, and binary files; as well as processing the authentication that many client/server applications require can involve multiple round trips across a slow WAN link. These factors conspire to defeat most WAN optimization vendors’ technologies. Many enterprise and Web 2.0 applications require both client- and server-side processing and perform very poorly over WAN connections. In an age of cloud-based services such as Exchange Web Services, SharePoint (MOSS), QuickBooks Online, Salesforce.com, Microsoft Live, and with many other distributed services, businesses and individuals are finding that their WAN connections represent the major performance bottleneck for web-based data that they depend on.

The Certeon aCelera technology contains a number of patented and proprietary technologies that are aimed at eliminating duplicate data transmission, anticipating and intercepting messaging locally, and providing the means to authenticate traffic without having to push or retrieve security information from remote sources.

Certeon holds several patents in this area that provide aCelera with:

• Industry leading transfer rates for content over a WAN link using the HTTP protocol
• Patented key pair handling technology that keeps authentication in the datacenter or home office, and doesn’t rely on remote processing for authentication
• Interception of SSL traffic, local processing, and direct aCelera to aCelera transfers of HTTPS traffic that results in transfer rates that are nearly identical to those achieved with unencrypted HTTP traffic

The aCelera HTTP and HTTPS Application Blueprints

As Web developers aim to make their sites more interactive much of the content delivered is dynamic content even though the underlying content being served is mainly static data objects. Since by design most web browsers and proxy servers do not cache dynamic content, a large majority of web-based data that is transferred can only be used once. This presents an opportunity to reuse content that has already been passed over a low bandwidth, high latency WAN connection, and doing so can greatly improve the performance of many Web-based applications.

The Certeon aCelera HTTP Application Blueprint was designed to address the problems involved in accelerating Web content over WAN links. By deploying aCelera at either end of a WAN connection, traffic sent over the WAN is identified from any of the standard HTTP and HTTPS commands (such as GET, PUT, or POST) using any of several RPC (Remote Procedure Calls). The data once recognized is objectified, and those objects are stored in cache both locally and remotely after being further compressed prior to transmission on a first pass. The HTTP Blueprint is able to extract data from the HTTP packet payload section, removing encapsulation and reframe object data so that more data can be sent with fewer packets. This has the effect of not only giving aCelera’s the industry leading performance in the data’s first pass, but it also greatly improves the ability to store data in the aCelera cache. When the same data is recognized again (second pass and beyond) aCelera sends a reference ID that allows the content to be reused essentially eliminating duplicate traffic. Since aCelera operates on blocks data, if a small portion of the data changes in a Web communication, then only that portion of the data is sent over the wire.

aCelera has a feature called “Pre-Cache Acceleration” (PCA) which helps speed up the rendering of Web pages by eliminating repetitive trips over the WAN connection to validate the freshness of content. As a browser loads the objects it uses in a Web page it will attempt to retrieve objects from the browser’s cache. Prior to loading an object the client’s browser will query the remote server with an HTTP 304 request for the “freshness value” of the object. The remote server then must respond. aCelera serves as a content proxy, storing information about an object’s freshness. Based on the answer obtained from the local aCelera additional trips over the WAN link can be eliminated and the browser can build the Web page faster.

aCelera also reduces the need for client authentication from a remote Web server by marking pages that require authentication when they are first recognized. When a client browser requests a Web page that needs to be authenticated the aCelera can signal that authentication must be attached to the HTTP 401 request for the page with the first request, thus eliminating additional requests back and forth over the WAN link that establishes the need for the inclusion of authentication credentials.