07 February 2008

Effects of Fibre Outage through Mediterranean

On January 31st, 2008, the NY Times, BBC, The Guardian, CNN and many others reported undersea cable cuts in the Mediterranean. There is also a Frequently Asked Questions (FAQ). One cable was damaged near Alexandria, Egypt, and another in the waters off Marseille, France. The two cables were damaged within hours of each other on Wednesday morning of January 30th 2008. Operators believe the damage was caused by ship's anchors during a heavy storm at sea. One of the cables, Sea Me We 4, is owned by 16 telecommunications companies along its route. The second cable, known as the Flag (for Fiber-optic Link Around the Globe) System, runs from Britain to Japan. The cables are separately managed and operated. The outages mainly affected the Middle East and Asia. Most disrupted communications were quickly rerouted through the remaining SEAMEW3 cable or fibres taking the other way around the globe. The cables involved are shown in the Telegeography map below. There are also world maps from Telegeography and Alcatel.
We decided to look at the impact on Internet connectivity as seen by the PingER project measurements seen from SLAC (near San Francisco in California). These are very simple ping echo measurements of Round Trip Time (RTT), Loss, jitter etc. the variations for a given path are typically caused by congestion. The measurements provide a sample of the Internet connectivity to over 150 countries of the world, countries that between them contain over 95% of the world's population and 99% of the world's Internet connected population.
Looking at the hourly ping losses (there are ~20 pings in an hour, so a loss of 1 ping is 5% loss) seen from SLAC for January 30th 2008 for large increases in losses which persisted to the end of the day (to avoid regular diurnal change, but unfortunately missing cases where the effect was removed by the end of the day, e.g. by re-routing), the main effects seen are shown in Table 1. In Table 1, the Loss before is the average loss before the outage, the Loss after is the loss after the outage started. The Sites affected is the number of sites monitored in the country that observed an effect, the total is the total number of sites monitored in the country. It is interesting that in many cases not all hosts were affected. This may be due to use of different carriers. The impact of such losses can make many applications unusable.
(IEPPM/Confluence)

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Lebanon Time-Line

Introducing Lebanon

Coolly combining the ancient with the ultramodern, Lebanon is one of the most captivating countries in the Middle East. From the Phoenician findings of Tyre (Sour) and Roman Baalbek's tremendous temple to Beirut's BO18 and Bernard Khoury's modern movement, the span of Lebanon's history leaves many visitors spinning. Tripoli (Trablous) is considered to have the best souk in the country and is famous for its Mamluk architecture. It's well equipped with a taste of modernity as well; Jounieh, formerly a sleepy fishing village, is a town alive with nightclubs and glitz on summer weekends.

With all of the Middle East's best bits - warm and welcoming people, mind-blowing history and considerable culture, Lebanon is also the antithesis of many people's imaginings of the Middle East: mostly mountainous with skiing to boot, it's also laid-back, liberal and fun. While Beirut is fast becoming the region's party place, Lebanon is working hard to recapture its crown as the 'Paris of the Orient'.

The rejuvenation of the Beirut Central District is one of the largest, most ambitious urban redevelopment projects ever undertaken. Travellers will find the excitement surrounding this and other developments and designs palpable - and very infectious.

Finally, Lebanon's cuisine is considered the richest of the region. From hummus to hommard (lobster), you'll dine like a king. With legendary sights, hospitality, food and nightlife, what more could a traveller want?

Introducing Beirut

What Beirut is depends entirely on where you are. If you’re gazing at the beautifully reconstructed colonial relics and mosques of central Beirut’s Downtown, the city is a triumph of rejuvenation over disaster.

If you’re in the young, vibrant neighbourhoods of Gemmayzeh or Achrafiye, Beirut is about living for the moment: partying, eating and drinking as if there’s no tomorrow. If you’re standing in the shadow of buildings still peppered with bullet holes, or walking the Green Line with an elderly resident, it’s a city of bitter memories and a dark past. If you’re with Beirut’s Armenians, Beirut is about salvation; if you’re with its handful of Jews, it’s about hiding your true identity. Here you’ll find the freest gay scene in the Arab Middle East, yet homosexuality is still illegal. If you’re in one of Beirut’s southern refugee camps, Beirut is about sorrow and displacement; other southern districts are considered a base for paramilitary operations and south Beirut is home to infamous Hezbollah secretary general, Hassan Nasrallah. For some, it’s a city of fear; for others, freedom.

Throw in maniacal drivers, air pollution from old, smoking Mercedes taxis, world-class universities, bars to rival Soho and coffee thicker than mud, political demonstrations, and swimming pools awash with more silicone than Miami. Add people so friendly you’ll swear it can’t be true, a political situation existing on a knife-edge, internationally renowned museums and gallery openings that continue in the face of explosions, assassinations and power cuts, and you’ll find that you’ve never experienced a capital city quite so alive and kicking – despite its frequent volatility.