Category: Cloud

GaesteBin: a secure pastebin for Google App Engine

TL;DR: gaestebin is a private, secure, open source pastebin for Google App Engine.

PastebinPastebins are incredibly useful. But most of the public pastebins are not suitable for sharing within a company (think code fragments, log messages etc.) and most private pastebins are either ugly (except hastebin!), hard to setup/maintain and usually forced to be behind the firewall (for security).

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Bitcasa: First Impressions


I got my invite for the Bitcasa beta last week but only got around to installing it yesterday. I’ve only used it sparingly thus far. If you are in a hurry, here’s the TL;DR version:

  • Users might find the “cloudify” model confusing
  • Built using osxfuse (not to be confused with MacFUSE) and Qt
  • Infinite storage sounds too good to be true. What’s the catch?
  • Building trust with users will take time

Cloudification and Confusion

Here’s Bitcasa on what cloudify does:

When a folder is Cloudified, a corresponding virtual folder is created on the Bitcasa server and the contents of your local folder are copied up to the server. When Connected to the Bitcasa server, any changes or additions to the folder will live on the server. When not Connected to the Bitcasa server, any changes or addition to the folder will live locally.

Just think about that for a second. The “cloudify” model sounds great in principle, but it does add a lot of complexity in terms of how users interact with the system. For instance, when I’m offline and make changes to one of my cloudified folders, that change happens presumably locally. I would assume that when I come back online, these changes are synced back to Bitcasa ala Dropbox. But what if I accidentally disconnect a folder, make some changes and then reconnect — per the FAQ, the changes made locally won’t be synced.

The consumer cloud storage is fairly mature right now and one can learn a lot by looking at how people respond to other systems. This thread on Quora is particularly insightful: again and again, simplicity comes up as one of the key reasons behind Dropbox’s success.

My prediction is that Bitcasa’s cloudify feature will be leveraged primarily by power users and the rest would end up using the default Bitcasa folder, Dropbox style.

Nuts and Bolts

Bitcasa seems to be built primarily using Qt. This isn’t a surprise: Qt is a mature, open source and cross-platform library.

$ otool -L Bitcasa
 /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 159.1.0)
 /usr/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.5)
 /usr/lib/libcrypto.0.9.8.dylib (compatibility version 0.9.8, current version 44.0.0)
 @executable_path/../Frameworks/libmacfuse_i64.2.dylib (compatibility version 10.0.0, current version 2.0.0)
 /usr/lib/libssl.0.9.8.dylib (compatibility version 0.9.8, current version 44.0.0)
 /System/Library/Frameworks/CoreServices.framework/Versions/A/CoreServices (compatibility version 1.0.0, current version 53.0.0)
 @executable_path/../Frameworks/QtWebKit.framework/Versions/4/QtWebKit (compatibility version 4.7.0, current version 4.7.4)
 @executable_path/../Frameworks/QtXml.framework/Versions/4/QtXml (compatibility version 4.7.0, current version 4.7.4)
 @executable_path/../Frameworks/QtGui.framework/Versions/4/QtGui (compatibility version 4.7.0, current version 4.7.4)
 @executable_path/../Frameworks/QtNetwork.framework/Versions/4/QtNetwork (compatibility version 4.7.0, current version 4.7.4)
 @executable_path/../Frameworks/QtCore.framework/Versions/4/QtCore (compatibility version 4.7.0, current version 4.7.4)
 /usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 52.0.0)
 /usr/lib/libgcc_s.1.dylib (compatibility version 1.0.0, current version 1105.0.0)

$ mount
Sample Videos on /Users/diwaker/Bitcasa/Sample Videos (osxfusefs, nodev, nosuid, synchronous, mounted by diwaker)
TryBitcasa on /Users/diwaker/TryBitcasa (osxfusefs, nodev, nosuid, synchronous, mounted by diwaker)
TryBitcasaDedup on /Users/diwaker/TryBitcasaDedup (osxfusefs, nodev, nosuid, synchronous, mounted by diwaker)

Note further that Bitcasa represents “connected” folders as mount points over the existing folders. This is why when you disconnect a folder and make changes, they won’t propagate to Bitcasa’s copy of that folder. They are using osxfuse which implies that Bitcasa is intercepting file system calls; this is in contrast to Dropbox-like systems that detect changes to the local filesystem asynchronously. I haven’t compared fine-grained read/write performance just yet.

Here’s a snapshot of the Bitcasa Folders UI:

Bitcasa also does some deduplication. Uploading 100MB of mostly random data took around 4 minutes on a pretty fat pipe which isnt’ bad at all. Copying that data back out took just as long, if not longer. A copy of the same folder took less than 10 seconds to cloudify!


Much has been said about Bitcasa’s security. However, most of the articles are concerned with a specific dimension of security: encryption.

A detailed discussion of Bitcasa’s security in general and encryption, in particular, deserves a post of its own. For now, suffice to say that even after several years of user experience, Dropbox still hit some pretty nasty security snafus in 2011. Like a lot of you, I’m very concerned about security, especially with a service that is offering me infinite storage for free! It takes time to build trust with your users — there’s no short cut.

Overall, Bitcasa is definitely interesting. Dropbox was almost beginning to monopolize the consumer cloud storage market, so some good competition will hopefully benefit the end users in the long run.

Some thoughts on iCloud

Sorry, all the sensationalist headlines were taken, so I had to pick something boring.

As we all know by now (read: probably 1% of the world’s population), at WWDC earlier this week, Apple spilled the beans on the upcoming iCloud, among other things. In this post, I wanted to share some of my thoughts on the much hyped iCloud (not that there is any dearth of opinions and articles on the subject, thanks to the echo-chamber that is Twitterverse and Blogosphere)


First off, some quick bullets summarizing what it is:

  • iCloud aims to make cloud storage painless, the idea being that your data should be available to you from all your devices, all the time.
  • It’s automatic and transparent. Apple is baking iCloud support deep into 9 different applications: iTunes, Photo Stream, Apps, Books, Documents, Backup, Contacts, Calendar and Mail. And that’s just the beginning.
  • It’s free. Upto 5GB — excluding purchased music, books, apps and photo stream.
  • Sync over the air: iCloud can sync across devices over wireless. As a concrete example, you’ll no longer need a cable to sync and backup your iPhone with your laptop.

Here are some cool things about iCloud:

  • Scan and skip upload (iTunes only): when dealing with large data sets (such as your movies and music collection), one of the main impediments to using cloud storage is the overhead of doing the initial import. With a 1Mbps uplink, a 10GB music collection will take a full day to upload. Of course, if the file you are trying to upload already exists somewhere in the cloud, you don’t need to upload it and this is exactly what iCloud does. Because of the iTunes store, Apple already has a library of 18 million songs (and counting) and detecting if two files are for the same song is a lot easier than for many other media types (say images or movies).
  • Storage APIs for developers: APIs are all the rage these days. By exposing the right set of APIs, Apple could attract developers to build iCloud functionality on other platforms (Android, for example). Unfortunately, the API is fairly limited at this point (key-value store or documents).
  • HP, Teradata, maybe EMC are rumored to have supplied bulk of the hardware in the spanking new datacenter that will be the backbone for iCloud.
  • Despite all the hoopla around “cloud” recently, it was still grounded firmly within the tech circles. Apple has the ability, experience and motivation to take cloud computing truly mainstream with iCloud.

What is NOT so cool:

  • Apple has a habit of exaggerating the novelty and efficacy of their features (remember Spaces?) Scan and skip upload is nothing new: it is just deduplication under the wraps — a well known technique in storage systems. Videos and photos will still have to be uploaded though — there’s no real shortcut for those. Of course, there are techniques to dedup arbitrary data and I hope Apple is leveraging them.
  • In the same vein, syncing of Mail, Calendar and Contacts is just catch up. Ever used Google? Likewise for Docs and Books. The delivery model is different — Apple apps work with the local data and sync when there’s connectivity. They haven’t touched upon conflict resolution, disconnected clients etc.
  • Implications for Dropbox: transparent, automatic sync across multiple devices is a phenomenally hard problem. Apple makes it sound like they’ve nailed it. It took Dropbox several years to address all the performance and security concerns. I’d wager Apple will run into its share of snags along the way.
  • Apples all the way: despite their claims, iCloud is designed to lock you in. Sure you may be able to leverage some of the features by installing additional software on a PC. But unless you are using an Apple device, you won’t get the full experience or service. Want your “reading list” available on Android (or Chome, for that matter)? Tough luck. Want your music available to other music players (open source players like Banshee and Amarok, god forbid)? How about your photo stream in Picasa?

Finally, there’s no doubt that iCloud will drastically alter the cloud landscape. However, Apple is focused mainly on the personal cloud — which is a good thing, they are playing to their strengths. It is also a great opportunity because the enterprise cloud market is still wide open. The requirements, challenges and “killer apps” in that market are very very different than the personal/consumer cloud market. Should be fun!