DMM.com

DMM.com Censorship in China and North Korea: Technical Blocks and Workarounds

What DMM.com is

DMM.com launched in 1999 as a digital marketplace under DMM.com LLC, a subsidiary of Otsuka Toshindo. The platform operates as Japan's largest seller of downloadable content—including video, games, e-books, and software. It serves millions of registered users primarily across Japan, with regional expansion into other Asian markets. The service has grown to handle over 2 million titles and processes substantial transaction volumes, making it a significant player in Japan's digital economy.

Why it's censored

China blocks DMM.com through the Great Firewall apparatus, enforced by the China Internet Information Center (CNII) and Ministry of Public Security. The blocking targets the platform's adult content library, which comprises roughly 30–40% of DMM's catalog. Chinese content regulations under the Regulations on Internet Information Services (2022 revision) and earlier Administrative Measures on Internet Publications explicitly prohibit distribution of sexually explicit material. Adult video, erotic games, and related media fall under prohibited content categories that trigger automatic blocking at the gateway level.

North Korea's censorship operates under a different logic. The regime maintains near-total internet isolation through the Korean Computer Center (KCC), the state monopoly controlling all connectivity. DMM.com is blocked not primarily for content reasons but because it represents foreign commercial infrastructure outside regime control. Bandwidth to external services is tightly rationed; foreign entertainment platforms receive de facto zero routing except in controlled government and military networks. The Democratic People's Republic does not publish formal content regulations, but blocking reflects broader state policy against unmonitored foreign access.

Technical blocking methods

China employs layered blocking targeting DMM.com. At the DNS level, the Great Firewall intercepts queries for dmm.com and returns null or false IP addresses. Simultaneously, IP-level filtering blocks known DMM data center ranges, including AS16509 (Amazon AWS, which hosts portions of DMM's infrastructure). Deep packet inspection (DPI) identifies SSL/TLS handshakes to dmm.com domains and terminates connections mid-session. Users attempting direct IP access encounter TCP reset packets. Some regional carriers add SNI filtering, inspecting the Server Name Indication field in HTTPS connections to identify dmm.com traffic before encryption completes.

North Korea's blocking is less technically sophisticated but more absolute. The regime's gateway routers at the China border (primary internet access point) lack routes to DMM infrastructure. Secondary blocking occurs through URL filtering on Kwangmyong, the domestic intranet, which blocks any reference to DMM or similar foreign services. International users with rare VSAT access face similar restrictions.

User workarounds

Users in China typically employ Virtual Private Network (VPN) tunnels to route traffic outside the Great Firewall before DNS resolution occurs. Protocol diversity matters; some providers use OpenVPN, others use WireGuard or proprietary protocols less detectable by DPI systems. Changing DNS resolvers to external providers (1.1.1.1, 8.8.8.8) sometimes bypasses local redirection but often fails when combined with IP blocking. Proxy chains and obfuscation techniques add another layer. North Korean users lack practical workarounds; accessing DMM requires physical departure or rare elite access to unrestricted networks.

Alternatives

DLsite, another major Japanese adult content platform, faces identical blocking in China under equivalent regulations. Pornhub and similar services are also blocked. Domestically censored alternatives in China include Bilibili and iQIYI for general entertainment, though these exclude adult content entirely. Users seeking non-censored Japanese digital goods may access regional platforms like GREE or Niconico, though these too face partial restriction in China depending on content categories.

Outlook

Restrictions in China are tightening, not easing. 2024 enforcement has intensified around adult content distribution following updated guidance from the Cyberspace Administration of China. North Korea's isolation remains static; no easing is anticipated. Japanese government diplomatic pressure on internet freedom has yielded minimal results, reflecting China's regulatory sovereignty and North Korea's isolation from international norms. DMM.com faces sustained long-term blocking in both jurisdictions.