Russia-Japan Cable Network (RJCN)

Overview

The Russia-Japan Cable Network (RJCN) is a bilateral submarine cable system connecting Japan and Russia. Spanning 1,800 km, it serves the corridor between the two countries across the Sea of Japan, providing a direct link between the Russian Far East and the Japanese coast.

Route and Landings

In Japan, the cable lands at Joetsu, located on the country's Sea of Japan coastline in Niigata Prefecture.

In Russia, the cable comes ashore at Nakhodka, a port city in Primorsky Krai in the Russian Far East.

Ownership and Operators

RJCN is jointly owned by KDDI and Rostelecom. KDDI is one of Japan's principal telecommunications carriers, while Rostelecom is Russia's state-controlled national telecommunications operator. The two-party ownership structure reflects the bilateral nature of the cable's route.

Status and Timeline

The cable entered service in 2008 and has been operational for approximately 18 years. No end-of-service date has been announced.

Regional Context

Japan is served by 38 submarine cable systems landing across 46 points, reflecting its position as a heavily connected node in the Asia-Pacific region. Russia's submarine cable infrastructure is comparatively smaller, with 12 systems landing across 24 points. At 1,800 km, RJCN is shorter than most cables touching these two countries, exceeding only 37% of the 43 other cables operating in the same corridor — a figure that underscores its focused, point-to-point purpose rather than any long-haul intercontinental ambition.

Among cables landing in Japan, regional peers such as EAC-C2C (36,500 km), APCN-2 (19,000 km), Trans-Pacific Express (17,968 km), and JUPITER (14,557 km) are substantially longer systems spanning multiple countries and ocean basins. RJCN, by contrast, is a compact bilateral link dedicated specifically to Japan–Russia connectivity, occupying a distinct niche within the broader network of cables serving Japan.

Measured performance over the past 60 days, based on 31 ping tests, shows an average round-trip latency of 68.6 ms, with a best recorded figure of 43.7 ms. These figures are consistent with the cable's 1,800 km span across the Sea of Japan.

Strategic Role

RJCN provides the direct submarine cable connection between Japan and Russia, linking Joetsu on Japan's Sea of Japan coast with Nakhodka in the Russian Far East. As one of a limited number of systems serving the Russia landing environment — where only 12 cables operate in total — it represents one of the few physical submarine pathways between Russian territory and the broader Asia-Pacific cable network anchored in Japan.