replify accelerator technical overview

Replify Accelerator Technical Overview

October 2010

© Replify 2010

V1.1


Commercial In Confidence of 12

Table of Contents Background ............................................................................................................................................. 3

Software-Based WAN Optimization ........................................................................................................ 3

Optimizations .......................................................................................................................................... 4

Protocol Optimization ......................................................................................................................... 5

CIFS Optimization ............................................................................................................................ 5

HTTP Optimization .......................................................................................................................... 5

HTTPS/SSL Optimization ................................................................................................................. 6

Other Protocols ............................................................................................................................... 6

De-Duplication through Replify XDR .................................................................................................... 6

Compression ....................................................................................................................................... 7

Optimization Effectiveness ................................................................................................................. 7

Deployment Scenarios ............................................................................................................................ 8

Branch Office to Data Center .............................................................................................................. 8

Individual Client to Data Center .......................................................................................................... 8

Location Awareness ............................................................................................................................ 9

Multi-Site Deployments ...................................................................................................................... 9

Reporting Functionality ......................................................................................................................... 10

Technical Requirements........................................................................................................................ 11

Component Overview ....................................................................................................................... 11

Replify Virtual Appliance ............................................................................................................... 11

Replify Client ................................................................................................................................. 11

Replify Enterprise Manager .......................................................................................................... 12

Extending WAN Optimization ............................................................................................................... 12

Summary ............................................................................................................................................... 12



Background Company networks are changing. Site and server consolidation is moving IT infrastructure from

branch offices to central locations, cloud computing is beginning to deliver IT services externally,

and users are needing more flexibility

to move between offices, work from

home and work remotely while

travelling. These changes mean that

more and more users are working

remotely from the applications they

are accessing day-to-day.

The applications that users are

accessing are also becoming more

network dependent, providing richer

experiences through web 2.0 interfaces, providing advanced collaboration capabilities, or allowing

users to participate in complex business processes.

More remote users and more content-heavy applications are pushing the requirement for WAN

Optimization technology. Replify Accelerator provides software-based WAN optimization focusing

on the user’s experience with the applications they use.

Software-Based WAN Optimization Traditional approaches to WAN optimization have made networks more efficient by providing a

hardware device located at each side of the network. These hardware devices control the

connection to the network and provide efficiencies. Hardware based solutions provide great

optimization but introduce deployment problems – IT management required on each side of the

network, costly purchase and upgrade processes, inability to support cloud scenarios or individual

remote workers. Hardware vendors are beginning to provide their capabilities in software –

however this has required re-engineering of their solutions leading to limited software versions

which remain as costly as their hardware predecessors.

Replify Accelerator has been designed from the beginning to provide the capabilities of hardware

based WAN optimization entirely in software – with algorithms appropriate to meet the

requirements of low-footprint clients, and virtualized commodity servers.

As a software-based WAN Optimization solution, Accelerator has the following advantages:

Full optimization capabilities within an individual client or software appliance

Easy to deploy within cloud infrastructures

Extensive optimizations efficiently in software

Straight-forward deployment, without changing the network

Targeted acceleration for problem applications or specific users

Scales up and down without friction as needs change

Server

Consolidation

Cloud Services

Remote

Workers



Replify Accelerator intercepts traffic destined for accelerated application servers, routing the traffic

through the Replify software on the client side of the network (either an individual PC client, or

through a shared virtual appliance). The client side software routes traffic to the Replify server-side

appliance. With traffic routed through Replify Accelerator on both sides of the network, the Replify

software can remove redundant unnecessary calls across the network, pre-fetch and bulk transfer

and remove as many bytes from the transfer. All traffic destined for the application server is routed

through Replify Accelerator, allowing the acceleration software to learn traffic patterns and provide

the maximum optimization.

Routing of the application server traffic is performed through a number of possible techniques:

Individual client intercepts traffic destined for application servers

The local virtual appliance acts as the default gateway for a branch or remote office

Traffic in a site is routed to the local virtual appliance using policy based routing

Traffic in a site is routed through the WCCP protocol which automatically routes traffic to be

optimized via the local Replify virtual appliance

Static routing is configured between clients and the local virtual appliance

Once the traffic is routed through Replify Software within the client network, it is then optimized

and passed through the server-side virtual appliance. The server-side virtual appliance re-creates

the original network request and sends it on to the application server being accelerated. Any

response from the application server goes through the same process in reverse back to the user.

By understanding the traffic patterns and connections being made between the client and the

application servers across the WAN, Replify Accelerator can remove redundant calls, and remove as

many bytes as possible transferring across the WAN link.

Optimizations Replify Accelerator provides comprehensive WAN Optimizations specifically designed for the

requirements of software-based scenarios. Accelerator provides three categories of optimization:

Protocol Optimization

De-duplication through Replify XDR

Compression

WAN

DATA

CENTE

R

Mobile

worker

Branch

Office

Mobile

worker

Mobile

worker



Protocol optimization is the only optimization which is directly dependent on the actual protocol

being used across the network. De-duplication and compression provide benefits regardless of the

protocol or data being transferred.

Protocol Optimization Protocol optimization looks at the message sequences for specific protocols, and ensures that

redundant requests are removed and not passed over the WAN connections. The Replify client or

client-side virtual appliance recognizes requests made to application servers and identifies the

protocols being used within the requests. Many protocols do not make the most efficient use of the

network, making requests across the network which are not required, or which ask for information

in small, inefficient amounts.

Replify provides a number of protocol optimizations to make protocols more efficient. These

combine with the other optimizations to ensure that traffic to and from systems such as email (via

MAPI or HTTPS), file shares, collaboration and ERP applications are fully optimized.

CIFS Optimization

A typical example of an inefficient protocol is the Common Internet File System (CIFS) protocol. CIFS

provides the file share capabilities built into Windows based solutions. The CIFS protocol was not

designed with wide area networks in mind – it transfers information across the network in small

requests, resulting in very inefficient use of the network for large files. Small requests across the

network are very sensitive to any latency on the connection which results in the end user experience

suffering.

Replify Accelerator intercepts CIFS requests made across the network and identifies when large

content is about to be transferred. Instead of making small requests for the content across the

WAN, Replify Accelerator pre-fetches blocks of content in a pre-fetch buffer. Accelerator then

serves content from the pre-fetch buffer on the client side of the network instead of making further

small requests across the network.

Pre-fetching significantly decreases the number of requests across the network, and avoids the

latency of the network affecting the end user experience. For example, the number of requests for a

2Mb file across a wide area network with 200ms latency decrease from 234 requests down to 3

requests with Accelerator pre-fetching. This decreases a user’s wait time from over a minute to 15

seconds. See the Replify CIFS whitepaper for more information on Accelerator’s CIFS optimizations.

HTTP Optimization

Replify Accelerator’s HTTP Optimization includes header identification and manipulation, NTLM

authentication pooling, and HTTP de-chunking. These protocol optimizations focus on ensuring that

WAN



the block caching and compression optimizations work effectively on the largest possible data within

the network request.

HTTPS/SSL Optimization

Often connections across the WAN are encrypted using HTTPS/SSL encryption. Encryption ensures

communication is private. To an observer it appears as if the requests contain random data even if

the same requested document is being returned. This encryption can prevent pattern matching and

compression optimizations built into a WAN optimization system from operating.

Replify Accelerator provides optimization for encrypted information – ensuring patterns are

recognized between requests, and allowing compression to work effectively. Optimizing encrypted

information involves providing the Replify Virtual Appliance within the data center with the

certificate of any encrypted application server. Certificates never move outside the data center. All

data transferred from client to Replify VAs on to the target application server will continue to be

made over fully encrypted connections, ensuring the privacy of the communication is maintained.

See the Replify SSL whitepaper for more information on Accelerator’s optimizations in encrypted

scenarios.

Other Protocols

Accelerator has various other optimizations that help identify and accelerate traffic for particular

protocols. Other protocols currently supported include MAPI (via RPC or over HTTP), print servers,

DoubleTake, iSCSI, RDP, SQL and VNC. If a protocol is not currently identified by Replify Accelerator,

it will still be optimized through de-duplication and compression. Replify is continuing to enhance

Accelerator with new protocols at each release.

De-Duplication through Replify XDR XDR is a key technology of the Replify Accelerator product. XDR de-duplicates patterns of information

as the information passes across the network. It is bi-directional, replacing patterns of data with

cache references as information is sent to, or received from, the application servers.

As Accelerator is used to optimize connections to an application server, the XDR technology learns

the patterns being transferred between users and the server. If any pattern is seen more than once,



a reference to the pattern is sent across the network instead of the original block of data. This

removes considerable traffic from the network for similar content.

The algorithms built into the XDR technology ensure that Replify Accelerator can quickly determine if

a pattern within traffic passing across the network has previously been seen and can be replaced

with a reference. The cache size available for XDR is configurable. The XDR technology ensures that

patterns seen most frequently remain within the cache and patterns which are infrequently used are

dropped from the cache. XDR can make use of in-memory and disk-based cache to ensure the

maximum throughput possible.

In office-to-office scenarios, with a local virtual appliance in each office, XDR provides shared caching

for all users in the office, providing greater optimizations for all. Since the cache is based on content

that would be sent or received by individual users, security of the content is always maintained.

XDR works regardless of the type of traffic or application server, and detects patterns across multiple

unrelated applications. For example if similar content is seen in an email attachment and a file share

copy. XDR is extremely successful within collaboration scenarios where information is retrieved,

changed and uploaded again. Since it is bi-directional, and protocol independent, XDR will replace

data with references if, for example, a user downloads a file from a content management application

and subsequently sends it within an email.

See the Replify XDR whitepaper for more in-depth information on Accelerator’s de-duplication

functionality.

Compression The final step in Replify Accelerator’s optimizations is to compress any remaining information which

would be sent across the wide area network. With modern data types like HTML and XML being text

based – and with the frequent transfer of text-based content, compression plays an important part

in removing bytes from the network by minimizing the data that needs to be transferred.

Compression is also very effective on print traffic.

Optimization Effectiveness Replify Accelerator’s various optimizations combine to remove a high percentage of bytes from the

network, and improve the user experience to applications across remote connections. Accelerator

typically takes between 70 and 90% of information away from the network, depending on the data

and patterns of information passing across the network.



Deployment Scenarios As a software-based solution Replify Accelerator has the widest deployment capabilities. It can be

deployed easily to cloud or highly distributed scenarios and can accelerate individual connections

through a client installation on a laptop.

All deployments can be installed and configured centrally without the need for end-user

involvement. The software can be reconfigured centrally through the administration interfaces, or

through active directory.

Branch Office to Data Center For branch offices with a number of users and with some IT infrastructure, a Replify Accelerator

Virtual Appliance can be deployed within the branch office site. This branch office virtual appliance

is peered with the virtual appliance on the data center side – and provides the local Replify

Accelerator capabilities for all the users within the branch office site. User’s access to the

application servers must be routed through their local virtual appliance. This routing can be done

through configuration, by using the WCCP protocol, by configuring the virtual appliance as a

gateway, or by using the Replify client. Optimization can be provided without requiring a software

installation on the client machines.

Individual Client to Data Center For branch offices without IT Infrastructure, or for users travelling or working from home, Replify

provides an individual client that provides the same optimizations as the virtual appliance within the

branch office. The low-footprint client can be installed and configured without end-user

involvement. The client runs as a local service intercepting traffic destined for the application

servers, and routing the traffic to the remote virtual appliances. The client can run invisibly to the

end-user.



Location Awareness Typically, users connect from a range of different locations – moving between offices, working from

home or on the road. This means that a static deployment with users always being accelerated

through the same office-based virtual appliance would not work for many scenarios. Replify

Accelerator’s location awareness can automatically determine the location for a connecting user,

and connect to the most appropriate virtual appliance. For example, while the user is within an

office, the Accelerator routes the traffic through the local office virtual appliance, thereby taking

advantage of the shared cache provided within the local virtual appliance. When outside the office,

traffic will be optimized by the local client running on the user’s machine. Location Awareness is

achieved by understanding the network addresses that users connect from, or by tagging users

belonging to particular groups.

Multi-Site Deployments Many real world scenarios deployments are complex – all applications and file servers are not

centralized in a data center, but are distributed throughout a number of branch offices. Replify

Accelerator works in a distributed environment by ensuring that office-based virtual appliances

behave not just as branch office client accessing data center virtual appliances, but also accelerate

access to application servers available locally within their own networks. Replify uses a combination

of location awareness, virtual appliance peering, and client tagging to accelerate traffic for remote

users accessing applications wherever they are located. A Replify Accelerator system can be

configured to include multiple virtual appliances to provide failover and resilience.



Reporting Functionality The Replify Virtual Appliances and Enterprise Manager both provide comprehensive reporting

functionality on the optimizations that are being provided for particular sites, for specific application

servers, for groups of users and right down to the optimizations provided for individual users. The

reporting functionality clearly shows the data savings that are delivered by Replify Accelerator.

1 Optimization by Protocol

2 Live Traffic View showing actual (optimized) and effective (raw) traffic



3 Traffic by Protocol

Technical Requirements

Component Overview

Replify Virtual Appliance

Replify Virtual Appliances installed within operational sites create an acceleration mesh which

optimizes inter-site traffic between the chosen applications and end-users.

The Virtual Appliance can run on commodity hardware within almost any virtualization hosting

environment required. Replify provides images for all the common virtualization platforms.

Memory requirements for the virtual appliance are dependent on the traffic, number of users and

the amount of caching desired. The virtual appliance can run in as little as 350Mb of memory for

non-cached scenarios. For typical deployments with caching we recommend 2Gb of RAM.

The processor and disk requirements are again dependent on traffic, users and caching. We

recommend assigning dual processors to the virtual appliance, and 40Gb of disk space if caching is

required.

Replify Client

The Replify Client is a Windows service which is installed on the end-point devices. The Replify Client

can provide application acceleration in exactly the same way as a Virtual Appliance, but for an

individual device. Client intelligence called “location awareness” means that the client will use a local



Virtual Appliance if one is present, giving the additional benefit of shared caching across multiple

users.

Processor and memory overhead of the Replify Accelerator windows client is negligible. Disk usage

depends on the cache configured for each user.

Replify Enterprise Manager

The Replify Enterprise Manager (REM) provides centralized configuration and control of your Replify

deployment, with detailed reporting on all of your Clients and Virtual Appliances. The REM provides

Clients and VAs with their application acceleration rules and also controls the licensing across an

enterprise or managed service provider.

The REM processor and memory requirements are dependent on the number of users in the overall

system. Disk usage is negligible. For typical scenarios we recommend assigning a REM with 512Mb

of memory and a single processor.

For detailed sizing of a Replify Accelerator system which is specific to a particular scenario, please

contact Replify Support ([email protected]).

Extending WAN Optimization Replify Accelerator ensures that network connections between users and applications are used as

efficiently as possible. In many scenarios, however, a user cannot depend on the availability or

quality of a network. Network issues should not stop the user from accessing, updating and adding

to information within mission critical applications accessed across the network. Replify works to

improve Remote Application Usability, even in scenarios where network is not always available.

Accelerator’s companion product Replify Syncstor provides a synchronized store allowing users

frustration-free uninterrupted access to application content regardless of the status of their network

connection. For more information on Replify Syncstor, see http://www.replify.com/products/replify-

syncstor/

Summary

Replify Accelerator’s unique software-based WAN optimization functionality provides significant

acceleration of network connections, improving usability for users accessing applications remotely.

The software is designed to meet a very broad range of deployment needs including highly dispersed

offices and large numbers of remote users. Protocol optimizations, bi-directional, block level de-

duplication and compression combine to provide 70-90% offload in typical scenarios. The software-

only algorithms are designed to provide optimizations in low-footprint installations with commodity

hardware.

mailto:[email protected]

http://www.replify.com/products/replify-syncstor/

http://www.replify.com/products/replify-syncstor/

replify accelerator technical overview

Technology

replify client

extending wan optimization

replify xdr

protocol optimization

cifs optimization

http optimization

httpsssl optimization

optimization effectiveness