Cardinal Blues: St. Louis, Missouri

Recently there have been a lot of activities in order to get our RDA Recommendations for Data Citation implemented. This included a trip to St. Louis where I have been invited to discuss details about the data infrastructure at the center of biomedical informatics (CBMI) at the Washington University of St. Louis. Besides having a very productive workshop, I also got the opportunity to see a little bit of St. Louis. The city may not be within the top ten cities to visit for Europeans, but it has a lot to offer and see. Please find a few impressions below.

General Tips

The Lambert-Saint Louis International Airport (STL) is pretty easy to reach and not far away from the city. There is a local light railway connecting the airport with the city. The 2 hours ticket for the MetroLink only costs 4$ and this should be sufficient for reaching your hotel. The ticket also includes the bus. As probably in many cities in the US, public transport is not that well. It is enough to do some sight seeing, but as you will see most of the locals have and use cars. Also I was advised that public transport is not that safe after dark (as are some areas in St. Louis in general).

The bus system is quite difficult to use if you so not have a data plan for your cell phone. I would advice to buy a prepaid SIM card for the US, which I failed to do in advance. I couldn’t easily find anything suitable to buy locally, so I had to rely on my Osmand+ offline map. There is not one center in st. Louis, but rather different neighbourhoods. I found Uber to be a great alternative to the public transport in terms of convenience and safety. Not having a data plan, I had to use available Wifis to book the car. You do not need any additional data exchange, as you also receive the details via text message (e.g. number plate) and the driver would shout your name if he can’t see you immediately.

Delmar Loop and Central West End

The Delmar Loop and Central West End are both areas with a lot of restaurants and bars. An interesting place is the Blueberry Hill, where Chuck Berry played and is still playing his famous guitar riffs.

Gateway to the West

The Gateway Arch is the  landmark of St. Louis and truly impressive. I used my jetlag to be there early, which I would recommend. You can buy the tickets in advance on the Gateway Arch web site. You can go to the top of the bow with a tram, which is quite an experience. The train trolleys are pretty small but (as everywhere) there is good air condition. The view is breathtaking and you can stay at the platform a long a you want. You can also book a boat cruise on the Mississippi, but this is not really impressive. The paddle steamers are actually fake and there is not much to see besides the (still impressive) Arch and the sky line.

Close to the Arch is the Old Court House which hosts an exhibition on the dark times of slavery, where St. Louis played a central role. The visit is free. Nearby is the ball park which is also worth a visit, if you are into baseball.

Forest Park, Zoo and Museums

The Forest Park is one of the largest city parks in the world and with its area of more than 5.55 km2 even larger than the Central Park in NY (haven’t been there myself yet, but sure sounds great! :-)). The park is beautiful, but also not all areas are designed for pedestrians. The park also provides a Zoo which you can enter free of charge (and there are not even queues). The zoo is really nice and exhibits a lot of (more or less exotic) animals. There is also the Missouri History Museum and the Saint Louis Art Museum, both of which are very nice. I accidentally paid an entrance fee at the Art Museum, which adds the amazing carpets exhibition (if you are into carpets, which I am not).

City Museum and City Park

The city museum is not really a museum but rather a playground for children and adults. It is one of the more crazier sights and great fun, especially if you like to climb around. It could be quite challenge estimate if you fit through the tunnels and climbing obstacles. At some point I was afraid that I could probably make it through the local newspaper as getting stuck was very likely. Wear sport equipment.

Even more impressive is the City Garden, which features a lot of statues and sculptures from famous artists. It is an oasis in the city and a nice place to recover from the City Museum.

Botanical Garden

St. Louis also provides a very nice botanical garden, which is definitely one of the top sights. The entrance fee was just 8$ and totally worth it. Everything is very well maintained, but the blue fountain does not seem to be organic.

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Bypassing Blocked Ports in (Public) Wifi Networks

Wifi networks at conferences or hotels often block certain ports, either for enhancing security  or simply by misconfiguration. Blocking ports can be used for preventing some applications from accessing the internet via their access points. Other usages can be to force users to use encrypted protocols, instead of their clear text alternatives. In order to make this process easier, in many cases the ports which should be allowed are whitelisted, whereas everything else is blocked. If your company mail server uses a rather exotic port for some reason, sending and receiving emails does not work. Eduroam is an example, where different policies and configurations are in place, where often the port 25 of mail servers is blocked.

You can use the following command to verify if a port is blocked or open:


telnet mail.example.org 25

If you receive the timeout after some time, the port is very likely to be blocked.


Trying 111.222.1.0 ...

telnet: Unable to connect to remote host: Connection timed out

Fortunately SSH allows tunneling connections, as long as its standard port 21 is open, which is often the case. All you need is a server with an SSH enabled account outside of your current network, which can connect to the mail server. The following command establishes such a SSH tunnel and connects your local port 25 via an SSH secure tunnel to your web server, where the tunnel exits and connects to your mail server.


sudo ssh -L 25:mail.example.org:25 user@web.server.org

You need to enter your password for your user account on the web server here. As soon as the tunnel is established, you can connect any service to your localhost and all traffic on port 25 gets tunneled via your server. If you now try the telnet example again, you should be able to connect.


telnet localhost 25

Trying 127.0.0.1...

Connected to localhost.

Escape character is '^]'.

220 Email Service

How to establish an SSH tunnel in Windows is described elsewhere.
You can now use this tunnel also in your email program such as Thunderbird, to send emails and bypass the blocked port by tunnelling.Note the localhost as the new server address. This is the only thing that you need to change.

Thunderbird SMTP via Tunnel

In some cases the tool will detect that the certificate does not match. So you need to accept the certificate warning or add the certificate by your mail server address manually in the dialogue.

 

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Lesbos: Ein Zwischenbericht

Heute fand der Social Event im Rahmen der IPICS statt. Um kurz nach 9 Uhr ging es mit dem Bus (siehe Bild) zum ersten der drei Zwischenstopps, der Ouzo Fabrik. Uhrzeit-bedingt war die Kostprobe doch eher was für Hartgesottene, aber die kurze Führung war sehr nett.

IMG_20150712_093816

Die Firma gehört mittlerweile dem französischen Pernot-Ricard Konzern, worüber die 30 Angestellten sehr froh sind. Anderenfalls wären wohl nur mehr hab so viele Mitarbeiter dort, denn durch die erweiterte Produktpalette kann flexibler auf die Nachfrageschwankungen reagiert werden. Somit riecht es dort nicht nur nach Anis, sondern auch nach Kräuterschnaps und Gin. Weiter gings zum Oliven-Öl-Museum, in dem wir die Geschichte der kommunal betriebenen Olivenölpresse seit 1910 und deren Auswirkungen auf die Gemeinde in einem griechischen Video mit englischen Untertiteln kennen lernen durften.

Durch diese Mühle konnte dort grundlegende Infrastruktur kommunal finanziert werden und so wurden beispielsweise Schulen, Altenheime und weitere soziale Einrichtungen errichtet. Auch dort gab es wieder eine Kostprobe, leider aber kein Öl zu kaufen.

IMG_20150712_133306

Während der Fahrt stellte sich bald heraus, dass unser Busfahrer M. perfekt Deutsch spricht, da er mit seinen Eltern, die damals als Gastarbeiter in Deutschland arbeiteten, in Hessen lebte und dort bis zu seiner Pensionierung gearbeitet hatte. M. war sehr an der Lage in Österreich interessiert und begann von sich aus sehr bereitwillig über seine Erfahrungen und Einschätzungen der aktuellen Lage zu erzählen.

Die vielen Flüchtlinge, die uns auch auf dieser Fahrt wieder auf der Straße entgegen kamen, kommen  laut M. von der Türkei aus über das etwa 5km breite Meer nach Molyvos. Verlassene, vermutlich undicht gewordene Boote finden sich an den Stränden, was uns auch einer der Vortragenden der Summerschool mit Fotos bestätigen konnte. Man findet auch allenthalben Schwimmwesten in der Nähe des Strandes. In Molyvos wortwörtlich gestrandet, schlagen sich die Flüchtlinge die etwa 65km lange, kurvige und teilweise steile Straße bis zum Inselhauptort Mytilini durch, wo sie sich registrieren lassen können. In Gruppen von 10 bis 30 Personen wandern die Flüchtlinge unter der griechischen Sonne ohne Hab und Gut, teilweise mit Kleinkindern entlang der Straßen. Herr M. meinte, dass die Flüchtlinge Nachts auf den Straßen schlafen und er deswegen besonders vorsichtig fährt. Mitnehmen darf er sie nicht, auch wenn er wollte, denn das werde bestraft und ist nicht gerne gesehen. Sobald sich die Flüchtlinge registrieren konnten, wandern sie zu einem der Lager weiter oder versuchen vom Hafen aus mit einer Fähre Richtung Athen weiter auf das europäische Festland zu wandern.

Sein eigenes Leben betreffend, überlegt Herr M. trotz Pensionierung noch einmal nach Deutschland zu gehen um dort Arbeit als Fernfahrer zu finden. Sein Sohn ist 27 und findet auf der Insel und in Griechenland keine Beschäftigung, trotz Universitätsabschluss in Informatik und intensiver Jobsuche. Er möchte ihm helfen, denn im Gegensatz zu Herrn M. Spricht sein Sohn noch kein Deutsch. Generell ist es so, dass die Jungen, die gut ausgebildet sind und die, die können verständlicherweise versuchen ins europäische Ausland zu migrieren, um dort Arbeit und somit eine Zukunft zu finden. Ob jene, die gehen jemals zurückkehren können ist fraglich, meint Herr M.,der unabhängig von der aktuellen Diskussion um den Verbleib Griechenlands in der Eurozone und weiteren Hilfspaketen davon ausgeht, dass es wohl mindestens 20 Jahre dauern wird, bis es wieder Arbeit für viele geben wird. Um sich selbst macht er sich keine Sorgen, denn er finde immer Arbeit, notfalls im Ausland. Seine Frau und sein kleines (Enkel?)kind verstanden nicht, was er uns hier verriet.

Dass er und seine Landsleute nur 60€ pro Tag abheben können, entlockte ihm nur ein kehliges Lachen.  So viel Geld hätte er seit vielen Jahren nicht mehr zur Verfügung. Was M. viel mehr Sorgen bereitete ist die Liquidität der Händler und ins besondere der Tankstellen. Als Berufskraftfahrer ist er noch mehr auf verfügbare Treibstoffe angewiesen. Denn auch Benzin und Diesel werden nur in Bar gehandelt und zwar nicht nur mit dem Endkunden, sondern auch mit den Mineralölfirmen. Was das bedeutet, kann man sich ausrechnen, denn in einen Tanklaster passen mehrere zehntausend Liter Treibstoff. Dementsprechend viel Bargeld wir hier auf der Insel hin und herbewegt, was auch ein gewisses Sicherheitsrisiko darstellt, weswegen Benzinlieferungen nun mittels bewaffneten Sicherheitsdiensten bewacht werden. Jetzt ist mir auch klar, warum mit Europcar das Auto nur mit einer Viertelfüllung übergeben hat und nicht voll, wie vertraglich vereinbart. So musste ich selbst Tanken und als Tourist hat man genügend Bargeld mit.

Als Ursache für die Misere verortet Herr M. unter anderem die laxe Pensionierungspolitik, insbesondere von Militär und Polizei. Er kenne persönlich mehrere Bundesbedienstete, die mit 45 Jahren kerngesund in die Pension geschickt wurden. Das habe System. Auch seine Frau, die an der Universität bei einem Reinigungsdienst beschäftigt war, ist mit 51 gegangen. Er selbst ist nun 61 und gerade pensioniert worden. Bei ihm stimme das Verhältnis der Beitragsjahre, aber selbst bei seiner Frau war es wohl viel zu wenig.

Als Abschluss der Rundreise auf der Insel besichtigten wir noch Molyvos, die wohl schönste Stadt hier auf Lesbos. Wir tauchten wieder in die heile Welt der Touristen ab, die noch gar nichts von den Spannungen und den vielen Baustellen merken. Erst als wir wieder am Busparkplatz in unser Reisevehikel einsteigen, werden wir von den gut 50 Flüchtlingen wieder daran erinnert, wie sehr die Lebensbedingungen und Realitäten auseinander gehen, einzig entschieden durch die Gnade des Geburtsortes.

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Use a TP-Link TL-WR710N Router as a Repeater with OpenWRT

Although most Hotels I have recently been to offer free wifi, the connection is often barely usable or only works within one single sweet spot of the room where it is impossible to get work done. Especially when you are traveling having a working network connection is essential. As the available connectivity if often frustrating, I invested 20€ into a pocket wifi router which I would like to use as a range extender. I bought a TP-Link TL-WR710N as it is tiny and comes with a USB-Port. This is quite nice as as power plugs seem to be really expensive to build as most hotel rooms only offer a very limited amount.

router2

 

 

The  TL-WR710N offers five modes of operation:

  • Router mode
  • Client mode (connects ethernet devices to an existing wifi)
  • Repeater mode (extends existing wifis)
  • Access point mode (create a wifi hotspot from a wired connection)
  • WISP Client

Unfortunately the firmware which is installed on the device is very instable and barely usable for my purpose. I could not get connectivity by using the software which is pre-installed although it would offer a nice interface for all the mentioned modes.

Open source software to the rescue! Fortunately there exists a OpenWRT version which can be easily installed and which empowers this little device quite a bit. Have a look at the OpenWRT homepage and ensure that you have a supported hardware version (in Austria you will most likely get the EU 1.2 version with 8MB flash memory and 32MB RAM). You can use the upgrade dialog in the original firmware in order to upload the OpenWRT firmware. Be careful during these steps and avoid power outage and upload errors. Once you installed the new firmware, just follow these steps in order to setup a range extender with OpenWRT.

1) Connect your laptop with an Ethernet cable to the TL-WR710N router.

2) Establish a telnet session. The default IP is 192.168.1.1

telnet 192.168.1.1

There is no standard password.
3) For security reasons you should use a SSH session. To do so, you need to set a new root password by issuing the following command in the telnet session.

passwd

You will be prompted to enter the new root password twice. After you set the password, the SSH daemon becomes active and telnet gets disabled. Exit the telnet session with

exit

4) Connect via SSH by using the following command:

ssh root@192.168.1.1

5)
In the next step you need to configure the network interfaces. We want to have one Ethernet port eth1, one loopback device lo and of course the wireless interface wlan0.
Use the vi editor and open this file

vi /etc/config/network

6) Enter this interfaces into the opened file.

config interface 'wan'
        option ifname 'wlan0'
        option proto 'dhcp'

config interface 'loopback'
    option ifname 'lo'
    option proto 'static'
    option ipaddr '127.0.0.1'
    option netmask '255.0.0.0'

config interface 'lan'
    option ifname 'eth1'
    option force_link '1'
    option type 'bridge'
    option proto 'static'
    option ipaddr '192.168.1.1'
    option netmask '255.255.255.0'
    option ip6assign '60'

Save and close with :wq

7) Now we just need to configure the wireless connection. Use

vi /etc/config/wireless

to open the file.
8) Enter this wireless connection details below:

config wifi-iface
      option device radio0
      option network wan
      option mode sta
      option ssid 'WEAK-NETWORK-SSID'
      option encryption psk2
      # option encryption none
      # option encryption wep
      # option encryption psk
      # option encryption psk2
      option key 'PASSWORD'

config wifi-device  radio0
    option type     mac80211
    option channel  11
    option hwmode    11g
    option path    'platform/ar933x_wmac'
    option htmode    HT20
    # REMOVE THIS LINE TO ENABLE WIFI:
#    option disabled 1

# This is the bridged interface
config wifi-iface
    option device   radio0
    option network  lan
    option mode     ap
    option ssid     'REPEATED-WIFI'
    # option encryption none
    option encryption psk2
    option key 'mobileAP'

This wireless configuration contains the details how to connect and thereby extend an existing wireless network. In the configuration example above the name of this network is WEAK-NETWORK-SSID and the password for the PSK2 secured network is PASSWORD. Other encryption methods you could use are

              # option encryption none
              # option encryption wep
              # option encryption psk
              # option encryption psk2 

The second interface REPEATED-WIFI is your new, repeated wifi network where you then connect your laptop or your mobile phone with.

9) Reboot the router with this command

reboot

You should then see a second wifi with the name REPEATED-WIFI in the available networks list. As the small router still has a better range than some devices, you should have a nicer connection.

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Visiting Iceland

In July this year I had the opportunity to present my work at the DATA2013 conference which located at the Reykjavík University. After the conference I appended two days in order visit the country. So far, this has been the most exotic place I have been and I was deeply impressed by the beauty of Iceland. I booked a day trip with a local bus company and visited the main sights, including the Strokkur Geysir in the Haukadalu valley, the Gullfoss waterfall, a geothermal power plant and the Þingvellir national park. On the next day I went to the Blue Lagoon geothermal spa, which was awesome (and expensive :-)).

Due to the price level in Iceland, I stayed budget hostels. The first on (Hostel 66) is a bit run down and a bit solitary, but staff was great and I had my own bathroom. What I had to learn was that its not necessarily the room that causes a weird smell, its the hot water and the sulfur that it contains 🙂 I then moved to Hostel B47 which is really central and rather modern. Next time I would probably go to the Kex Hostel, because its frequented by a lot of young people and they have a great bar to meet other travellers.

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