w w w. e g n y t e. c o m Egnyte Local Cloud Architecture White Paper Revised June 21, 2012
Table of Contents Egnyte Local Cloud Introduction page 2 Scalable Solutions Personal Local Cloud page 3 Office Local Cloud page 4 Enterprise Local Cloud page 6 Local Cloud Architecture Permission (ACL) Enforcement page 8 Initial Synchronization page 9 Incremental Synchronization page 10 Network Optimization Delta Sync page 11 File Checksum Signatures page 11 Batching page 11 Configurability Granular Folder Selection page 12 Synchronization Frequency page 12 Active Directory Integration page 12
Egnyte Local Cloud Introduction Egnyte HybridCloud combines the speed and security of local storage with the accessibility of the cloud. This "no compromise" approach provides businesses with file storage, sharing access and backup from anywhere, online or offline. Egnyte HybridCloud is comprised of two components: Egnyte Cloud File Server and Egnyte Local Cloud. Egnyte Local Cloud replicates data between local storage (e.g. personal computer hard drive, network-attached storage, virtual appliance running on unified storage) and the cloud. Files on the Local Cloud are automatically synchronized with the Cloud File Server, providing users with flexible remote file access or fast local network access.
Scalable Solutions Personal Local Cloud (personal and home office) Egnyte Personal Local Cloud (PLC) provides individual users local access to files on their personal computer. PLC is installed on the user s Windows or Mac computer, and synchronizes files between the local hard drive and the cloud. Users can access files directly through Finder on their Mac or Explorer on their Windows personal computer, providing an intuitive way to open, edit, save and manage their files.
PLC enforces permissions from the cloud seamlessly, allowing users to synchronize only the folders and sub-folders they have access to. Users also have the ability to select which folders and subfolders are synced on their hard-drive; minimizing bandwidth and storage space for only the files that are essential to them. Example: A Product Manager only needs local access to the Product Management folder and Sales folder. Those parent folders are selected and the files within are automatically synced with the Egnyte Cloud File Server, providing a local copy of those folders on the computer. Office Local Cloud (small office and branch office) Egnyte Office Local Cloud (OLC) is the first of Egnyte s multi-user products that provides fast LAN speed file access and collaboration with commercial network-attached storage (NAS) devices. OLC is fully optimized and integrated with the industry-leading NAS product line (ReadyNAS) from NETGEAR. With the built-in OLC add-on, the ReadyNAS is transformed into a local file server, enabling fast file access and sharing.
Since OLC is meant for multi-user access, it allows entire offices to have fast local file access and collaboration through bi-directional synchronization with the cloud. Companies can also deploy multiple instances of OLC in different offices, allowing multiple locations to collaborate on common sets of files. OLC enforces permissions at the point of access for all users accessing the NAS device. Therefore, if a user was set to have Read Only access to the Finance folder in the cloud, they will only read access to the Finance folder on the NAS device as well. OLC exposes a CIFS share to the user, allowing files to be accessed from a native mapped drive on Windows and from an SMB mount on Mac computers. OLC can also be integrated with Active Directory for seamless user authentication. Egnyte OLC is designed to synchronize only a selected subset of the namespace (i.e. unlike all or nothing). This allows the specific office location to choose the data set based on the business need (e.g. the office has only Product Management and Sales teams and only that subset needs to be available for local access).
Administrators can also configure sync frequencies (schedule versus interval), and bandwidth limits that allow offices to cap the bandwidth used for synchronization. Enterprise Local Cloud (multi-office and enterprise) Egnyte Enterprise Local Cloud (ELC) is a multi-user product that provides fast LAN speed access to files from any local hardware device capable of running virtual appliances. ELC provides similar functional capabilities as OLC, but is intended to leverage any existing storage and server investments. ELC can be deployed on a range of platforms (Windows, Linux, VMware ESX) and can leverage either local storage or attached storage as a SCSI target. ELC is also designed to scale as business needs grow. As the user count and storage grow, ELC can be scaled up by allocating more memory, CPU capacity and disk storage. Since ELC is meant for multi-user access, it allows entire offices to have fast local file access and collaboration through bi-directional synchronization with the cloud. Companies can also deploy multiple instances of ELC in different offices, allowing multiple locations to collaborate on common sets of files. ELC enforces permissions at the point of access for all users accessing the local storage. Therefore, if a user was set to have Read Only access to the Finance folder in the cloud, they will only read access
to the Finance folder on the NAS device as well. ELC exposes a CIFS share to the user, allowing files to be accessed from a native mapped drive on Windows and from an SMB mount on Mac computers. ELC can also be integrated with Active Directory for seamless user authentication. Egnyte ELC is designed to synchronize only a selected subset of the namespace (i.e. unlike all or nothing). This allows the specific office location to choose the data set based on the business need (e.g. the office has only Product Management and Sales teams and only that subset needs to be available for local access). Administrators can also configure sync frequencies (schedule versus interval), and bandwidth limits that allow offices to cap the bandwidth used for synchronization.
Local Cloud Architecture At the heart of Egnyte Local Cloud, is a powerful synchronization engine that's platform neutral at its core, but extensible to provide platform specific customizations that deliver a seamless end user experience for each platform (e.g. PLC utilizes intuitive Explorer file functions on Windows). This common data synchronization logic allows Egnyte to deliver ongoing enhancements across all platforms simultaneously. Permission (ACL) Enforcement In a hybrid cloud infrastructure, it is crucial that permissions are uniformly enforced both in the cloud and through local storage. All Egnyte Local Cloud solutions offer strict permission enforcement from any user access point, a capability unique to Egnyte. Permissions set in the cloud are enforced locally by the synchronization engine. For example, a user who no access to the Finance folder in the cloud will not be able to access it through the local network either. Similarly, a user who has read only access to the Finance folder will only be able to read files in that folder locally.
All permissions rules allowed in the cloud (inheritance, exclusion, user and group level access) are mirrored to the Local Cloud seamlessly. The Local Cloud effects permission changes in the cloud by receiving and processing change events (e.g. a permission level was changed from read/write to read only). Specifically in the case of multi-user products (Office Local Cloud and Enterprise Local Cloud), the ACL has to be enforced across the entire set of users and folders that are available locally on the device. ACL enforcement is achieved by a patented permission enforcement module that traps all file system access. An optimized in-memory ACL database maintained by the module scales to deep file system hierarchies. This module can listen to events occurring on local files as well as a remote protocol stack. Initial Synchronization (seeding) For businesses with existing data on local storage, the first stage of Local Cloud implementation is seeding that data to the cloud. The initial synchronization is completed through a multi-threaded process. One thread scans the file system while another thread loads files that have been identified by the scan. This multi-threading process significantly reduces the time it takes to complete and load files from the initial scan. The synchronization engine also selectively compresses files based on type and size to minimize bandwidth. The amount of reduction is based on the compression ratio (e.g. 50-60% with Office
documents) and overhead incurred to compress the file. All transmissions between the local and external clouds occur over a secure (256-bit AES) SSL channel. Incremental Synchronization (event based) Once the initial scan and sync is complete, all subsequent synchronizations are driven based on event detection. Egnyte automatically detects any discrete file system events on both the Cloud File Server and local storage. Any file or folder actions (e.g. a user adding files online or renames a folder locally or in the cloud) are recorded as distinct events. This is driven by a persistent local event journal maintained by Egnyte s proprietary event module. The event module listens to events occurring on the local storage and subscribes to events with the local protocol stacks (CIFS etc). After the initial sync, all subsequent synchronizations process only the events that have occurred since the prior synchronization. Since event processing is proportional to the number of outstanding events, the synchronization time is independent of the data set size. For example, suppose the company has a file set of one thousand files and there are 10 new file events since the last synchronization; the time it takes to sync those 10 events is the same regardless of the original file set size, whether it's one thousand or one million.
Network Optimization Delta Sync All incremental synchronizations are highly optimized to reduce network traffic. Once a file has been synchronized to the cloud, any subsequent synchronization only relays the file change (delta) and not the entire file. This allows for efficient file editing and collaboration, without bottlenecking Internet bandwidth. File Checksum Signatures In order to prevent unnecessary resynchronization of file location changes, the synchronization engine utilizes file signatures for efficient processing. For example, suppose the Marketing sub-folder resides on the cloud, but users copy the sub-folder and all its contents to a different parent folder; the synchronization engine automatically detects the file signature and copies the Marketing sub-folder to the new parent folder, without having to resynchronize. This intelligent file management process prevents local storage from needlessly syncing the same data in different locations. Batching The Local Cloud synchronization engine leverages operational batching to achieve efficient synchronization. Multiple operations, such as file uploads, are batched together in certain situations to obtain maximum network efficiency, without compromising synchronization speeds.
Configurability Granular Folder Selection Egnyte provides administrators with the ability to select which folders are synced with the local storage at each office location (each Local Cloud instance). This allows for efficient file sync of folders and sub-folders at any level of data hierarchy, so only the important files are replicated for online and offline use. Example: A satellite sales office only needs offline access to the Product Management folder and Sales folder. Those parent folders are selected and the files within are automatically synced, providing copies for online remote access as well as local offline access. Synchronization Frequency Administrators have the ability to configure the synchronization frequency of each Local Cloud instance. This allows every office to customize the sync rate according to their needs. The synchronization frequency can be set at a defined schedule such as after business hours to optimize bandwidth, or at intervals ranging from several minutes to real time. Active Directory Integration Local Cloud solutions can be integrated with Active Directory for seamless user authentication.
About Egnyte Over 1 billion files are shared daily by businesses using Egnyte. Egnyte s unique hybrid cloud technology provides the speed and security of local storage with the accessibility of the cloud. Users can easily store, share, access and backup files, while IT has the centralized administration and control to enforce business policies. Egnyte, founded 2008, is based in Mountain View, California and is a privately held company backed by venture capital firms Kleiner Perkins Caufield & Byers, Floodgate Fund, and Polaris Venture Partners. For more information, please visit www.egnyte.com or call 1-877-7EGNYTE.