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Punched holes in the great firewall?

Punched holes in the great firewall?

I am in Shanghai right now and I was surprised that I could access the forbidden fruits, e.g. m.facebook.com:  1  172.31.24.1 (172.31.24.1)  1.359 ms  1.079 ms  1.049 ms  2  180.168.46.17 (180.168.46.17)  1.262 ms  1.180 ms  1.073 ms  3  10.10.96.145 (10.10.96.145)  29.356 ms  29.781 ms  29.607 ms  4  10.10.199.179 (10.10.199.179)  40.466 ms  40.220 ms  40.559 ms  5  203.131.250.221 (203.131.250.221)  40.208 ms  40.581 ms  40.139 ms  6  ae-0.facebook.chwahk02.hk.bb.gin.ntt.net (203.131.241.62)  41.732 ms  46.681 ms  42.098 ms  7  psw01a.hkg3.tfbnw.net (173.252.64.176)  42.154 ms    …

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Leaving Berlin, saying hello to Amsterdam

Leaving Berlin, saying hello to Amsterdam

Berlin continues to gain a lot of popularity, culturally and culinarily it is an awesome place and besides increasing rents it still remains more affordable than other cities. In terms of economy Berlin attracts new companies and branches/offices as well. At the same time I felt the itch and it was time to leave my home town once again. In the end I settled for the bicycle friendly (and sometimes sunny) city of Amsterdam. My main interest remains building reliable…

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C++, Qt and Treefrog to build user facing web applications

C++, Qt and Treefrog to build user facing web applications

In the past I have written about my usage of Tufao and Qt to build REST services. This time I am writing about my experience of using the TreeFrog framework to build a full web application. You might wonder why one would want to build such a thing in a statically and compiled language instead of something more dynamic. There are a few reasons for it: Performance: The application is intended to run on our sysmoBTS GSM Basestation (TI Davinci DM644x). By modern…

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HNBAP and RANAP support in Osmocom.org

HNBAP and RANAP support in Osmocom.org

Sysmocom is in the process of adding 3G support to OpenBSC. This is done in the nature of using an existing hNodeB Femtocell that exposes the Iuh interface. The binary protocol for Iuh (and related protocols) is defined using the Abstract Syntax Notation One (ASN.1) and the aligned packed encoding rules (APER) are used to encode/decode the data. After exploring several options LaForge picked the one that adds APER support to Lev Walkin’s ASN1 compiler, simplifies the 3GPP ASN.1 input…

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Adding menu items in redmine (e.g. a link to contact information)

Adding menu items in redmine (e.g. a link to contact information)

The Osmocom project is switching from a list of separate trac projects to a single instance of redmine. One German legal requirement is to publish contact information (Impressum) and it needs to be easily discoverable. The easiest seems to be to add this to the top level menu of our redmine. This way it will be available on all pages and just one (or two on mobile to open the menu) clicks away. The below can be placed in a…

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osmo-pcap capture on the edge and store in the center

osmo-pcap capture on the edge and store in the center

Imagine you run a GSM network and you have multiple systems at the edge of your network that communicate with other systems. For debugging reasons you might want to collect traffic and then look at it to explore an issue or look at it systematically to improve your network, your roaming traffic, etc. The first approach might be to run tcpdump on each of these systems, run it in a round-robin manner, compress the old traffic and then have a…

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A C++ project without Qt

A C++ project without Qt

My primary language is Smalltalk (Pharo and GNU Smalltalk) and I didn’t write much C++1x code yet and for a new project I decided to use C++ and experiment. The task was rather simple, receive a message, check if this message type needs to be re-written, start to parse it, make a MongoDB look-up, patch it, send it. While looking for MongoDB drivers for Qt I only found the pure C++ driver that is working with std::string, exceptions and only…

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OpenCore and Python moving to Github

OpenCore and Python moving to Github

Some Free Software projects have already moved to Github, some probably plan it and the Python project will move soon. I have not followed the reasons for why the Python project is moving but there is a long list of reasons to move to a platform like github.com. They seem to have a good uptime, offer checkouts through ssh, git, http (good for corporate firewalls) and a subversion interface, they have integrated wiki and ticket management, the fork feature allows…

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Build or buy a GSM HLR? Is there an alternative?

Build or buy a GSM HLR? Is there an alternative?

The classic question in IT is to buy something existing or to build it from scratch. When wanting to buy an off the shelves HLR (that actually works) in most cases the customer will end up in a vendor lock-in: The vendor might enforce to run on a hardware sold by your vendor. This might just be a dell box with a custom front, or really custom hardware in a custom chasis or even requiring you to put an entire…

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osmo-pcu and a case for Free Software

osmo-pcu and a case for Free Software

Last year Jacob and me worked on the osmo-sgsn of OpenBSC. We have improved the stability and reliability of the system and moved it to the next level. By adding the GSUP interface we are able to connect it to our commercial grade Smalltalk MAP stack and use it in the real world production GSM network. While working and manually testing this stack we have not used our osmo-pcu software but another proprietary IP based BTS, after all we didn’t…

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