From bcd3ab9475ebfb3fcb12124fff529e5472df94b3 Mon Sep 17 00:00:00 2001 From: gilbertchen Date: Mon, 22 Feb 2016 21:38:59 -0500 Subject: [PATCH] Update README.md --- README.md | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/README.md b/README.md index 91b9659..ee9f3d7 100644 --- a/README.md +++ b/README.md @@ -1 +1,18 @@ -# duplicacy-beta \ No newline at end of file +# Duplicacy: A new generation cloud backup tool based on Lock-Free Deduplication + +Duplicacy works with major cloud storage providers and at the same time offers all essential features of a modern backup tool: + +* Incremental backup: only back up what has been changed +* Full snapshot : even if each backup is incremental, it must appear to be a full snapshot independent of others +* Deduplication: identical files must be stored as one copy (file-level deduplication), and identical parts from different files must be stored as one copy (block-level deduplication) +* Encryption: encrypt not only file contents but also file paths, sizes, times, etc. +* Deletion: every backup can be deleted independently without affecting others +* Concurrency: multiple clients can back up to the same storage at the same time + +The key idea behind Duplicacy is a technique called **Lock-Free Deduplication**. There are three elements of lock-free deduplication: + +*Use variable-size chunking algorithm to split files into chunks +*Store each chunk in the storage using a file name derived from its hash, and rely on the file system API to manage chunks without using a centralized indexing database +*A *two-step fossil collection* algorithm to remove chunks that become unreferenced after a backup is deleted + +Getting Started