View source for Open Computer Network

{{Original research|section|date=April 2019}}

'''OCN''' (オーシーエヌ), or '''Open Computer Network'''(オープン・コンピュータ・ネットワーク:Ōpun Konpyūta nettowāku), is the largest [[Japan]]ese [[Internet service provider]], with over 7 million subscribers.<ref>[http://www.ocn.ne.jp/info/announce/2008/06/19_2.html OCN発表記事会員700万契約突破] ([http://www.google.com/translate_c?&sl=ja&tl=en&u=http://www.ocn.ne.jp/info/announce/2008/06/19_2.html machine translation])</ref> It is owned by [[NTT Communications Corp]], one of the largest [[telecommunication]] companies in the world. It offers [[dial-up]] and [[ISDN]], [[DSL]] up to 50&nbsp;Mb/s and [[Fiber to the x#Fiber to the premises|fiber]] up to 200 Mbit/s download and 100&nbsp;Mb/s upload.<ref>{{Cite web |url=http://service.ocn.ne.jp/hikari/wflets/charge/ |title=フレッツ光 料金シミュレーション ｜ フレッツ光（OCN 光 with フレッツ） |access-date=2014-06-02 |archive-date=2014-06-05 |archive-url=https://web.archive.org/web/20140605051403/http://service.ocn.ne.jp/hikari/wflets/charge/ |url-status=dead }}</ref>

As a result of regulations intended to promote competition, OCN themselves offer only internet service (routing); the physical line can be offered by NTT (the parent corporation), or by another company. Speeds up to 1&nbsp;Gb/s are offered in Western Japan, while in East Japan only 200&nbsp;Mb/s is officially offered for residential use, even though the underlying fiber infrastructure is capable of 1&nbsp;Gb/s.

OCN also offers an MVNO mobile broadband service called "OCN Mobile One", based on NTT Docomo's LTE infrastructure. Initially it started out as a data-only service, but more recently OCN Mobile One also offers an ''onseikake'' SIM card (音声対応SIMカード) that provides full service (data, SMS and voice) without requiring any calling app.<ref>{{Cite web |title=格安SIMカード＜料金・コース＞ {{!}} OCN モバイル ONE {{!}} OCN |url=https://service.ocn.ne.jp/mobile/sim/ |access-date=2023-02-10 |website=OCN インターネット接続（プロバイダー） |language=ja}}</ref>

==See also==
* [[Verio]]

==References==
<references />

==External links==
* [http://www.ocn.ne.jp/english/personal/option/roaming/ Official OCN website]
* [http://sciencelinks.jp/j-east/article/200410/000020041004A0170876.php Start of OCN Business Web Service and its Future] {{Webarchive|url=https://web.archive.org/web/20110717001243/http://sciencelinks.jp/j-east/article/200410/000020041004A0170876.php |date=2011-07-17 }} at Science Links Japan
* [http://www.ntt.com/ NTT communications]
* [https://www.spamhaus.org/sbl/listings/ocn.ne.jp OCN known as ocn.ad.jp is also the source of a large number of phishing spam emails and Malware distribution activity]
* [http://forum.spamcop.net/topic/16696-ocnadjp-spam/ Discussion regarding ocn.ne.jp as a source of spam/malware]

{{NTT}}

[[Category:Internet service providers of Japan]]
[[Category:NTT Communications]]


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