Riverbed Technology (RVBD)

Technology

The Riverbed Optimization System (RiOS) is our proprietary software platform that provides the core intelligence for our Steelhead products. To achieve performance improvements across a broad range of applications, RiOS integrates four key sets of technologies: Data Streamlining, Transport Streamlining, Application Streamlining and Management Streamlining.

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Data Streamlining

Our Data Streamlining technologies address bandwidth limitations in existing networks. Our patented approach can be applied to all data and applications that run over TCP to reduce bandwidth consumption by dramatically reducing the need to send the same data multiple times over the WAN. Data Streamlining also supports the classification of individual data packets for quality-of-service and route control.

In a non-optimized WAN setting, each time data is requested by a remote user, all of the data must be sent across the WAN, regardless of whether identical data (or an insignificantly modified version of the data) has previously been sent. In wide-area distributed computing environments where Steelhead products have been deployed, all of the requested data must be sent across the WAN only the first time data is requested by a user, at which time that data is stored by the Steelhead products on both sides of the network. In subsequent requests, redundant data segments will not be sent regardless of what application is requesting the data or which user is making the request. The detection of repetitive data patterns is very granular, with a typical segment of data being as small as approximately 100 bytes. This fine level of granularity enables Steelhead products to detect tiny changes in files, e-mails, web pages and other application data, sending only those changes across the WAN.

Each end-user request for data is sent directly to the intended authoritative application server as opposed to a cache that typically utilizes a copy of the data. Our Steelhead product intercepts the server response, identifies redundant data patterns and then sends only the new segments across the WAN to the end-user. All of the existing segments are represented by references which point to those already existing segments stored on the end-user side of the WAN connection. In this way, significantly less traffic needs to be sent to deliver large amounts of data to the end-user. In addition, this approach eliminates data consistency issues inherent in cache-based approaches.

Transport Streamlining

Transport Streamlining enhances the performance of the TCP protocol by increasing the amount of data carried per TCP round trip, thereby reducing the number of round trips required to move a given amount of data over the WAN. We accomplish this by both increasing the default TCP payload and by filling the window with references to data rather than actual data.

We also enhance TCP performance by reducing the time associated with creating new TCP connections (especially for small, short-lived transfers), adapting transfer parameters based on real-time network characteristics and assigning priority for necessary packet resends due to packet loss. A component of Transport Streamlining, High Speed TCP, also addresses the TCP chattiness and latency that is particularly pronounced in high speed connections (for example OC-12 (622 Mbps)). Another component of transport streamlining, MXTCP, is designed to address private networks with packet loss.

Application Streamlining

Application Streamlining provides a further mechanism to enhance the performance of specific applications. Many applications were designed for use over a LAN and require hundreds to thousands of interactions between client and server to execute even simple requests, such as opening a file. By understanding the semantics of particular application protocols, Steelhead products reduce chattiness, collapsing hundreds of client-server interactions into a few round trips over the WAN.

While most important business applications that run over TCP immediately benefit from Data Streamlining and Transport Streamlining, Application Streamlining enables us to add additional acceleration for specific applications. We have built specific Application Streamlining modules that

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support file, e-mail, web, ERP, and database application protocols (CIFS, MAPI, HTTP, Oracle Forms, SSL, Lotus Notes, NFS and MS-SQL and others). For example we have also built special modules to address protocol inefficiencies for common storage back-up and replication applications. We believe these applications are especially inefficient in wide-area distributed computing. We have designed our architecture to enable additional Application Streamlining modules to be incorporated easily over time.

Management Streamlining

Management Streamlining allows for simplified implementation and administration of our Steelhead products. Unlike alternative approaches which usually require changes to clients, servers, routers and switches or the addition of an overlay network of tunnels, Steelhead products are designed to be transparently installed in existing IT infrastructure with minimal administration. The auto-discovery capabilities of RiOS allow our Steelhead products to identify automatically all Steelhead products on the WAN, typically without a need to reconfigure any network infrastructure. Our products automatically intercept WAN traffic without any further configuration requirements to applications, clients, or other network infrastructure, while allowing non-optimized traffic to simply pass through.

Our RiOS software provides IT administrators with simplified management of Steelhead products through Command Line Interface (CLI), Graphical User Interface (GUI) and an optional Central Management Console.

Other key elements of Management Streamlining include touchless configuration options, over-the-wire software upgrades for Steelhead products, singular and grouped appliance management and customizable reporting analytics.

Technology

The Riverbed Optimization System (RiOS) is our proprietary software platform that provides the core intelligence for our Steelhead products. To achieve performance improvements across a broad range of applications, RiOS integrates four key sets of technologies: Data Streamlining, Transport Streamlining, Application Streamlining and Management Streamlining.

Data Streamlining

Our Data Streamlining technologies address bandwidth limitations in existing networks. Our patented approach can be applied to all data and applications that run over TCP to reduce bandwidth consumption by dramatically reducing the need to send the same data multiple times over the WAN. Data Streamlining also supports the classification of individual data packets for quality-of-service and route control.

In a non-optimized WAN setting, each time data is requested by a remote user, all of the data must be sent across the WAN, regardless of whether identical data (or an insignificantly modified version of the data) has previously been sent. In wide-area distributed computing environments where Steelhead products have been deployed, all of the requested data must be sent across the WAN only the first time data is requested by a user, at which time that data is stored by the Steelhead products on both sides of the network. In subsequent requests, redundant data segments will not be sent

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regardless of what application is requesting the data or which user is making the request. The detection of repetitive data patterns is very granular, with a typical segment of data being as small as approximately 100 bytes. This fine level of granularity enables Steelhead products to detect tiny changes in files, e-mails, web pages and other application data, sending only those changes across the WAN.

Each end-user request for data is sent directly to the intended authoritative application server as opposed to a cache that typically utilizes a copy of the data. Our Steelhead product intercepts the server response, identifies redundant data patterns and then sends only the new segments across the WAN to the end-user. All of the existing segments are represented by references which point to those already existing segments stored on the end-user side of the WAN connection. In this way, significantly less traffic needs to be sent to deliver large amounts of data to the end-user. In addition, this approach eliminates data consistency issues inherent in cache-based approaches.

Transport Streamlining

Transport Streamlining enhances the performance of the TCP protocol by increasing the amount of data carried per TCP round trip, thereby reducing the number of round trips required to move a given amount of data over the WAN. We accomplish this by both increasing the default TCP payload and by filling the window with references to data rather than actual data.

We also enhance TCP performance by reducing the time associated with creating new TCP connections (especially for small, short-lived transfers), adapting transfer parameters based on real-time network characteristics and assigning priority for necessary packet resends due to packet loss. A component of Transport Streamlining, High Speed TCP, also addresses the TCP chattiness and latency that is particularly pronounced in high speed connections (for example OC-12 (622 Mbps)). Another component of transport streamlining, MXTCP, is designed to address private networks with packet loss.

Application Streamlining

Application Streamlining provides a further mechanism to enhance the performance of specific applications. Many applications were designed for use over a LAN and require hundreds to thousands of interactions between client and server to execute even simple requests, such as opening a file. By understanding the semantics of particular application protocols, Steelhead products reduce chattiness, collapsing hundreds of client-server interactions into a few round trips over the WAN.

While most important business applications that run over TCP immediately benefit from Data Streamlining and Transport Streamlining, Application Streamlining enables us to add additional acceleration for specific applications. We have built specific Application Streamlining modules that support file, e-mail, web, ERP, and database application protocols (CIFS, MAPI, HTTP, Oracle 11i, SSL, NFS and MS-SQL). We have also built special modules to address protocol inefficiencies for common storage back-up and replication applications. We believe these applications are especially inefficient in wide-area distributed computing. We have designed our architecture to enable additional Application Streamlining modules to be incorporated easily over time.

Management Streamlining

Management Streamlining allows for simplified implementation and administration of our Steelhead products. Unlike alternative approaches which usually require changes to clients, servers, routers and switches or the addition of an overlay network of tunnels, Steelhead products are designed to be transparently installed in existing IT infrastructure with minimal administration. The auto-discovery

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capabilities of RiOS allow our Steelhead products to identify automatically all Steelhead products on the WAN, typically without a need to reconfigure any network infrastructure. Our products automatically intercept WAN traffic without any further configuration requirements to applications, clients, or other network infrastructure, while allowing non-optimized traffic to simply pass through.

Our RiOS software provides IT administrators with simplified management of Steelhead products through Command Line Interface (CLI), Graphical User Interface (GUI) and an optional Central Management Console.

Other key elements of Management Streamlining include touchless configuration options, over-the-wire software upgrades for Steelhead products, singular and grouped appliance management and customizable reporting analytics.

Technology

The Riverbed Optimization System (RiOS) is our proprietary software platform that provides the core intelligence for our Steelhead appliances. To achieve performance improvements across a broad range of applications, RiOS integrates four key sets of technologies: Data Streamlining, Transport Streamlining, Application Streamlining and Management Streamlining.

Data Streamlining

Our Data Streamlining technologies address bandwidth limitations in existing networks. Our patented approach can be applied to all data and applications that run over TCP to reduce bandwidth consumption by dramatically reducing the need to send the same data multiple times over the WAN. Data Streamlining also supports the classification of individual data packets for quality-of-service and route control.

In a non-optimized WAN setting, each time data is requested by a remote user, all of the data must be sent across the WAN regardless of whether identical data (or an insignificantly modified version of the data) has previously been sent. In wide-area distributed computing environments where Steelhead appliances have been deployed, all of the requested data must be sent across the WAN only the first time data is requested by a user, at which time that data is stored on the Steelhead appliances on both sides of the network. In subsequent requests, redundant data segments will not be sent regardless of what application is requesting the data or which user is making the request. The detection of repetitive data patterns is very granular, with a typical segment of data being as small as approximately 100 bytes. This fine level of granularity enables Steelhead appliances to detect tiny changes in files, E-mails, web pages and other application data, sending only those changes across the WAN.

Each end-user request for data is sent directly to the intended authoritative application server as opposed to a cache that typically utilizes a copy of the data. Our Steelhead appliance intercepts the server response, identifies redundant data patterns and then sends only the new segments across the WAN to the end-user. All of the existing segments are represented by references which point to those

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Table of Contents

already existing segments stored on the end-user side of the WAN connection. In this way, significantly less traffic needs to be sent to deliver large amounts of data to the end-user. In addition, this approach eliminates data consistency issues inherent in cache-based approaches.

Transport Streamlining

Transport Streamlining enhances the performance of the TCP protocol by increasing the amount of data carried per TCP round trip, thereby reducing the number of round trips required to move a given amount of data over the WAN. We accomplish this by both increasing the default TCP payload and by filling the window with references to data rather than actual data.

We also enhance TCP performance by reducing the time associated with creating new TCP connections (especially for small, short-lived transfers), adapting transfer parameters based on real-time network characteristics and assigning priority for necessary packet resends due to packet loss. A component of Transport Streamlining, High Speed TCP, also addresses the TCP chattiness and latency that is particularly pronounced in high speed connections (for example OC-12 (622 Mbps)).

Application Streamlining

Application Streamlining provides a further mechanism to enhance the performance of specific applications. Many applications were designed for use over a LAN and require hundreds to thousands of interactions between client and server to execute even simple requests, such as opening a file. By understanding the semantics of particular application protocols, Steelhead appliances reduce chattiness, collapsing hundreds of client-server interactions into a few round trips over the WAN.

While most important business applications that run over TCP immediately benefit from Data Streamlining and Transport Streamlining, Application Streamlining enables us to add additional acceleration for specific applications. We have built specific Application Streamlining modules that support file, E-mail, web and database application protocols (CIFS, MAPI, HTTP and MS-SQL). We have also built special modules to address protocol inefficiencies for common storage back-up and replication applications. We believe these applications are especially inefficient in wide-area distributed computing. We have designed our architecture to enable additional Application Streamlining modules to be incorporated easily over time.

Application Streamlining also provides for disconnected operations via the PFS feature. Using PFS, IT managers can provide remote users with policy-based access to files even during WAN failures.

Management Streamlining

Management Streamlining allows for simplified implementation and administration of our Steelhead appliances. Unlike alternative approaches which usually require changes to clients, servers, routers and switches or the addition of an overlay network of tunnels, Steelhead appliances are designed to be transparently installed in existing IT infrastructure with minimal administration. The auto-discovery capabilities of RiOS allow our Steelhead appliances to identify automatically all Steelhead appliances on the WAN, typically without a need to reconfigure any network infrastructure. Our appliances automatically intercept WAN traffic without any further configuration requirements to applications, clients, or other network infrastructure, while allowing non-optimized traffic to simply pass through.

Our RiOS software provides IT administrators with simplified management of Steelhead appliances through Command Line Interface (CLI), Graphical User Interface (GUI) and an optional Central Management Console.

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Table of Contents

Other key elements of Management Streamlining include touchless configuration options, over-the-wire software upgrades for Steelhead appliances, singular and grouped appliance management and customizable reporting analytics.