At my work, the backup appliances are typically physically located inside the LAN of our end users — much like other appliances such as routers, NAS devices or switches. Under normal circumstances that means that they are behind a NAT and are not reachable from the public Internet without a VPN or other tunneling mechanisms. For my employer’s customers, the Managed Service Provider (MSP), only being able to access their devices with direct physical access would be a major inconvenience.

Fortunately we’ve always provided a remote management feature called “Remote Web” for our customers: Remote Web lets them remotely access the device’s web interface as well as other services (mainly RDP, VNC, SSH), even when the device is behind a NAT.

Internally we call this feature RLY (pronounced: “relay”, like the owl, get it?). In this post, I’d like to talk about how we implemented the feature, what challenges we faced and what lessons we learned.

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I recently published a blog post about my open source file sync project Syncany. I explained the main idea of the project and also went into some of the details about where the development is headed. The post was the first of a series I am planning to write — showing what the project is about from different angles.

While the first post had a few technical elements, it mostly discussed the project’s process and its high level goals and ideas. In this second article, I’d like to go beyond the high level concepts and go a lot deeper into the different packages and modules of the software. Why, you ask? Because I think it might be interesting of others and because I believe that supporters and other developers will benefit from it.

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Many many moons ago, I started Syncany, a small open source file synchronization project that allows users to backup and share certain folders of their workstations using any kind of storage, e.g. FTP, Amazon S3 or Google Storage.

At the time of the initial annoucement of the project (May 2011), there was a big hype around it. I received many e-mails and lots of support from people around the world. People were excited because the features Syncany offers are great: File synchronization à la Dropbox, paired with storage flexibility (use-your-own), client-side encryption (sorry about that, NSA!), and intelligent versioning.

At the time, I didn’t actually release a runnable version of Syncany. The sole purpose of the announcement (on WebUpd8 and on the Ubuntu Podcast) was to get developers excited about the project in order to get help for the last steps of creating a somewhat stable release. Unfortunately, I was further away from this “stable release” than I could have imagined.

In this blog post, I’d like to recap the idea behind Syncany, what went wrong with the development, and how I brought the project back on track (or so I believe). I’ll also talk about what I plan to do with Syncany and how people can help (if they still want).

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This post introduces my Master’s thesis “Minimizing remote storage usage and synchronization time using deduplication and multichunking: Syncany as an example”. I submitted the thesis in January 2012, and now found a little time to post it here.

The key goal of this thesis was to determine the suitability of deduplication for end-user applications — particularly for my synchronization application Syncany. As part of this work, the thesis introduces Syncany, a file synchronizer designed with security and provider independence as a core part of its architecture.

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Many of the well known websites determine your location based on your IP address and restrict their content or functionalities based on the country you’re in. Some examples are Gmail (Germans get only @googlemail.com-addresses, legal reasons), YouTube (content is restricted by the GEMA), and Pandora (limited to US citizens) to name only a few. To circumvent these restrictions, being able to quickly get an IP address outside of your own country is most helpful.

To do exactly that I wrote a little script that will start your very own US proxy server in one minute using Amazon EC2. In combination with browser plug-ins such as FoxyProxy, the script enables you to route all your web traffic through a proxy on an Amazon-owned machine — with an IP address in the US, Ireland, Singapore, Tokyo or Sao Paulo (location of Amazon data centers).

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