Scalable NAS with SSD cache acceleration capability Synology DiskStation DS1520 is an ideal network-attached storage solution suitable for small office and IT enthusiasts. Two built-in M.2 SSD slots and Synology SSD Cache technology allow you to boost system IO and application performance. The scalable storage design of DS1520 lets you start small and expand storage capacity with Synology DX517 as your data grows. Optimize performance and capacity DS1520 provides two built-in M.2 SSD slots so that you can take full advantage of Synology SSD Cache functionality. Add SSD cache for up to 20 times faster IO response without using front drive bays. You can add 10 more drives with two Synology DX517 to expand storage capacity. Accelerate demanding applications A more powerful CPU speeds up computing-intensive applications. The new 4-core processor boosts photo indexing database response times and web PHP response efficiency. Easily categorize your photo memories smoothly manage files across computers and mobile devices and enjoy blazing fast web applications. Access and sync your files seamlessly Synology Drive provides a built-in universal portal to access your data anytime and anywhere and synchronize all your files across platforms including Windows macOS Linux Android and iOS. Learn more Sync files on demand Save the storage space and network bandwidth of your PC. Go back in time Easily retrieve previous versions of your shared files. Back up your data Protect your files with scheduled backups or in real-time. Real-time collaboration on your private cloud Synology Office is a collaboration package combining the convenience and usability of the public cloud with private cloud privacy and security. It enables seamless collaboration on documents and spreadsheets in a protected environment.