And The Gold Medal Goes To...

David Belson
Sr. Director, Internet Research & Analysis

The PyeongChang 2018 Winter Games are underway, and all eyes are on South Korea, with nearly 3,000 athletes from over 90 countries around the world representing their countries across a myriad of events. The slogan of the 2018 Olympic Winter Games is "Passion. Connected." According to the Organizing Committee, 'connected' signifies the openness of the host city, where every generation can participate in the Games – no matter where they are – thanks to Korea’s cutting-edge technology and cultural convergence.

Presumably, the vast majority of participants and spectators arrived in the country by air, likely through flights to Incheon International Airport. Others may have arrived by boat, with ferry services available from both China and Japan. However, the rest of us are attending the Olympics virtually, getting real-time results and streaming video of our favorite events over the Internet.

This focus on connectivity got us thinking... how are those bits getting to the users consuming them? More specifically, how is the Internet carrying those event results and how are the source video streams getting out of South Korea to end user Internet networks around the world?

Given South Korea's geographic and geopolitical location (on a peninsula, connected to the Asian continent through North Korea), the country's Internet traffic is heavily reliant on submarine cables to reach the rest of the world. TeleGeography's Submarine Cable Map is an excellent free and regularly updated resource, and provides great insight into submarine cable connectivity from South Korea. As shown in Figure 1 below, there are three primary submarine cable landing points in South Korea – cables come ashore in Shindu-Ri, Keoje, and Pusan.

Figure 1: Submarine cable connections to South Korea, as shown by Telegeography's Submarine Cable Map

Currently, a total of nine submarine cables carry data to and from South Korea. Based on data from Telegeography, the SeaMeWe-3 cable reaches the most countries (33), while Japan is the country most well-connected to South Korea, with a connection to all nine cables. China and Taiwan are also very well connected to South Korea, both with connections to six cables. Connections to Europe are more limited, with countries there connected via the SeaMeWe-3 cable. In addition, South Korea is connected to the United States via two cables, landing in two different cities in Oregon. A table including more specific information about the nine submarine cables and the countries that they are connected to can be found below.

While these submarine cable connections provide a physical perspective on South Korea's Internet connectivity to the rest of the world, they don't give any real sense of the paths that packets ultimately take -- that is, to get from South Korea to other countries, what intermediate countries do those packets transit through? Oracle Dyn performs hundreds of millions of Internet measurements (traceroutes) each day to determine Internet paths and latencies, so to answer that question, we looked at the results of millions of those traceroutes over a one-week period from Oracle Dyn vantage points located in South Korea to targets in countries around the world. By geolocating the IP addresses seen in the hops of each traceroute, we can determine which countries the paths pass through.

Figure 2 below illustrates the most popular countries that our traceroutes pass through, for measurements from South Korea to countries in a given region. In keeping with the Olympic theme, we awarded the top three through-countries for each region a Gold, Silver, or Bronze medal based on the percentage of traceroutes that passed through them en route to a country in the region.  The percentages shown will not add to 100% because multiple through-countries will appear in a given traceroute, and there are additional through-countries beyond the top three observed. (A table showing the member countries for each region in Figure 2 can be found at the end of this post. The Western Europe, Eastern Europe, Northern Europe, North America, and East Asia regions were chosen by counting the total number of Olympic athletes from each country and aggregating by region - these five have the most athletes. The South America and Africa regions were included to gain a more complete global perspective.)

Internet paths from South Korea

Figure 2: Awarding Gold, Silver, and Bronze medals for through-country presence in traceroutes from South Korea

Looking at the measurements to targets in Europe, it is worth noting the differences in the top through-countries for the three regions. To countries in Western and Northern Europe, the United States takes the gold, present in over 40% of the traceroutes, while Germany just edges out the United States in traceroutes to countries in Eastern Europe. The Netherlands took the bronze for presence in traceroutes to Western and Eastern Europe, with Great Britain in that position for Northern Europe. Although the FLAG and SeaMeWe3 cables connect South Korea with a number of European countries, the underlying peering and transit relationships appear to prefer sending traffic in the other direction, heading east across the United States, instead of west directly to Europe. These longer paths through the United States see higher latencies than those heading directly to Europe.

Not surprisingly, the United States takes the gold for path measurements to North America, present in over three-quarters of the traceroutes, in part because there are no direct submarine cable connections from South Korea to Canada or Mexico. Japan and Hong Kong place a distant second and third respectively, with a smaller number of traceroutes heading through those countries before heading to/through the United States.

The United States also takes first place as a through-country for traceroutes headed towards countries in South America. Japan again earned a silver medal, but Great Britain's third-place finish is extremely interesting, even if it is present in only two percent of the traceroutes. We have found that in a small number of cases, South America-bound traffic from South Korea takes a path through European countries including Great Britain, before heading across the Atlantic Ocean through the United States. The latencies seen in the paths through Europe to South America are generally higher than those that take an eastern route through the United States.

The results of measurements to countries in East Asia offer little surprise, with Japan taking the gold medal, present as a through country in just over half of the traceroutes due to multiple connections to South Korea, as well as other countries in the region. Hong Kong and China, both well-connected to South Korea and other regional countries through multiple submarine cables, earned the silver and bronze respectively.

Finally, in examining Internet paths from South Korea to endpoints in Africa, we found some very interesting results. Great Britain earned the gold medal as a through-country in the greatest percentage of traceroutes, followed by the United States and Germany. It is interesting to note that Great Britain's first place percentage was significantly lower than the gold medal percentage found for most of the other regions (except Eastern Europe) and that the spread between the three top finishers was also fairly small, again in contrast to most of the other regions. These results indicate that for traceroutes to African targets, there is a longer tail of through-countries, representing a greater diversity of paths.


South Korea is well known for its strong national broadband connectivity, with some of the highest connection speeds in the world, but its connections to the rest of the world are primarily reliant on submarine cables. However, despite the cable connections from South Korea to a number of other countries, millions of traceroutes indicate that the United States is positioned as a through-country in the largest number of those measurements to endpoints in multiple regions around the world. Across the seven geographical regions reviewed in this post, the United States earned four gold medals (Western Europe, Northern Europe, North America, and South America) and two silver medals (Eastern Europe and Africa), failing to be among the top three through-countries only in measurements to East Asian countries.

Appendix: Submarine Cables Connected to South Korea







Asia Pacific 

FLAG North Asia  
Loop/ REACH 
North Asia Loop 

Cable Network 

New Cross 
Pacific Cable 





































































































Hong Kong 


































































































































Saudi Arabia 






























Sri Lanka 








































United Arab Emirates 










United Kingdom 










United States (Oregon) 





















Appendix: Regional Country Lists

Western Europe Austria, Belgium, Switzerland, Germany, France, Liechtenstein, Luxembourg, Monaco, Netherlands
Eastern Europe Bulgaria, Belarus, Cyprus, Czech Republic, Hungary, Moldova, Poland, Romania, Russia, Slovakia, Ukraine, Kosovo
Northern Europe Aland Islands, Denmark, Estonia, Finland, Faroe Islands, Great Britain, Guernsey, Ireland, Isle of Man, Iceland, Jersey, Lithuania, Latvia, Norway, Sweden, Svalbard and Jan Mayen
East Asia China, Hong Kong, Japan, North Korea, South Korea, Mongolia, Macau, Taiwan
North America Canada, Mexico, United States
South America Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands, French Guiana, South Georgia and the South Sandwich Islands, Guyana, Peru, Paraguay, Suriname, Uruguay, Venezuela
Africa Angola, Burkina Faso, Burundi, Benin, Botswana, Democratic Republic of the Congo, Central African Republic, Congo, Ivory Coast, Cameroon, Cape Verde, Djibouti, Algeria, Egypt, Western Sahara,Eritrea, Ethiopia, Gabon, Ghana, Gambia, Guinea, Equatorial Guinea, Guinea-Bissau, British Indian Ocean Territory, Kenya, Comoros, Liberia, Lesotho, Libya, Morocco, Madagascar, Mali, Mauritania, Mauritius, Malawi, Mozambique, Namibia, Niger, Nigeria, Reunion, Rwanda, Seychelles, Sudan, Sierra Leone, Senegal, Somalia, South Sudan, Sao Tome and Principe, Swaziland, Chad, Togo, Tunisia, Tanzania, Uganda, Mayotte, South Africa, Zambia, Zimbabwe


Be the first to comment

Comments ( 0 )
Please enter your name.Please provide a valid email address.Please enter a comment.CAPTCHA challenge response provided was incorrect. Please try again.Captcha