Category: Uncategorized

Today the Let’s Encrypt initiative has announced that only 3 months after opening to the public, 1 million certificates for encrypting web traffic have been issued. 90% of the sites for which certificates have been requested did not encrypt their traffic before. In other words Let’s Encrypt’s mission to foster adoption of HTTPS by making it simple to get a certificate is working very well indeed!

This, by the way, also applies to this web site as I also use a Let’s Encrypt SSL certificate! I’ve previously hosted this blog at Typepad and one of the many reasons to leave was to get my site’s data traffic properly encrypted during transport. One nice side effect of this is that I no longer need to establish a VPN tunnel to write posts during my daily commute as everything is encrypted now.

Congratulations to Let’s Encrypt!

In the good old fixed line SIP world things are straight forward when a SIP user wants to call someone: INVITE, TRYING, RINGING, OK and you are there. In the VoLTE world things are a bit more complicated as the service tries to replicate the circuit switched telephony service. Here, a media stream can already sent before the receiving party answers the call so the caller hears an alerting (ringing) tone or even music in some cases. This is what’s known as early media in VoLTE and there are two ways how this is done in practice:

Continue reading VoLTE – Some Thoughts On Early-Media

In theory the 1 terabyte Samsung 840 Evo SSD I use in my notebook has a sustained write performance of well over 400 MB/s according to this fabulous review over at Anandtech. That is two thirds of the theoretical maximum speed the SATA 3 interface can deliver. While this is all nice and well I wondered how fast the SSD would be in combination with my notebook and my typical usage scenarios.

Continue reading How Fast Is That SSD In My Notebook?

By default, Owncloud is configured to handle files up to a size of 512 MB. While that’s probably good enough for most, I do run into this limit rather often. There are instructions how to increase the limit from an Owncloud point of view but when I recently wanted to transfer a 2.7 GB file my setup failed outside of Owncloud. It took me a bit before I found out how to fix it so I thought I put together all things I have now learned about how to configure a system for large file transfers in Owncloud with a number of security and privacy tips thrown in for good measure.

Continue reading Pushing My Owncloud File Size To 3 GB

Ever since I discovered last year that Opera’s web browser on my smartphone was responsible for strange queries to my web server from China to generate a thumbnail image (see ‘When Opera Calls From China‘) it had been at the back of my mind that Opera is not open source and hence I have little trust in it. These days it also seems like Opera is going to be sold to a Chinese consortium which would make it even less attractive for me to continue using it. Time to change to another browser on my Android based devices then. How about Firefox?

Continue reading Time To Switch From Opera to Firefox On Mobile – At Least For Me

Quite strange that only Bruce Schneier has picked up on this so far but researches have developed a proof of concept of how to exploit HID (Human Interface Device) USB dongles for wireless mice and keyboards to accept keystrokes from rouge third party transmitters.

Continue reading MouseJack Vulnerability – Have You Already Patched Your Mouse?

Eduroam is a great Wi-Fi login system for students and researches that works with certificates for secure access of on-campus Wi-Fi networks and has the added benefit that Eduroam users can attach to any other Eduroam network around the globe without changing their Wi-Fi configuration. That’s the theory and paper is patient. So when I recently was at the University of Utrecht in the Netherlands I tested if the theory holds up with an Eduroam setup of the University of Vienna.

Continue reading Eduroaming in Utrecht

Theoretical Internet speeds in fixed line and mobile networks keep rising, which is a nice thing. Unfortunately, round trip delay times are not decreasing at the same rate, mostly due to physical limits these days which at some point will limit the maximum throughput of a single TCP stream no matter how fat the pipe is and how fast a server can deliver data. So where is this limit?

Continue reading What Is My Theoretical Top Internet Speed?

Today I came across this great article by Robert Penz in which he describes measures how companies can reduce the risk of Ransomware encrypting their files on network shares and other devices in the local network. Also, he describes how a company can prepare itself in case it still happens to reduce their downtime as much as possible. I found one of his suggestions of particular interest: Snapshots of network shares.

Continue reading Good Advice To Block, Detect and Mitigate Ransomware Damage In Companies

When it comes to investigative reporting in the telecommunication domain, German telecoms news website Teltarif certainly is at the forefront. Recently they noticed that the public network coverage maps of one of the network operators in Germany now show that in many cities, they have deployed LTE in three different frequency bands.

Continue reading One German LTE Network Operator Now On-Air with 50 MHz