ResearchFree Expression Online

Update on threats to freedom of expression online in Vietnam

Cross posted from the ONI Blog.

Information openness has come under further threat in Vietnam, as the ongoing suppression of critical voices within the country may be strengthened through recently proposed regulations regarding use of the Internet. The new regulations seek to further criminalize and ban controversial web content, which combined with Vietnam’s long history of Internet censorship could further restrict an already limited information environment. Those same regulations also seek to impose new restrictions on bloggers, a community that has long experienced detainments, intimidation, and assaults.

In the wake of these proposed extensions to the country’s already strict information controls regime, OpenNet Initiative (ONI) conducted in-country testing to document and analyze state-level filtering of online content. This brief outlines the new restrictions proposed in the country, provides background about ONI’s past research in Vietnam, and reports the results of ONI’s most recent tests for Internet filtering.

Recent developments: New regulations and continued crackdown on bloggers

In recent months, a number of significant developments in Vietnam have threatened to further limit an already restricted information space. A draft decree seeks to impose new regulations on Vietnam’s information space, potentially increasing the government’s ability to censor content and prosecute bloggers. These new proposed regulations accompany ongoing targeting of critical bloggers in Vietnam, who continue to be imprisoned, harassed, and assaulted for their writings.

Draft decree

In April 2012, the Ministry of Information and Communication introduced the Decree on the Management, Provision, Use of Internet Services and Information Content Online1, which would force foreign content providers to increase cooperation with Vietnamese officials by removing content deemed illegal2 and potentially housing data centres within the country.3 The proposed decree would introduce stricter rules against the posting of critical or slanderous content online, as well as impose additional restrictions on users, including the requirement that users use their real names online and that bloggers post their real names and contact information on their blogs.4 Vague wording in the proposed decree would prohibit “undermining the grand unity of all people,” “undermining the fine customs and traditions of the nation” or “abusing the provision and use of the Internet and information.”5 The proposed regulations were widely criticized6 upon their introduction and were not formally introduced by the original June 2012 target date. As of August 2012, the implementation date of the new regulations remains unclear.

Threats to bloggers

ONI’s last country profile7 of Vietnam documented a pattern of extensive harassment and imprisonment of bloggers, a trend that continues today. Since 2011, reports have continued to emerge of harsh action against bloggers, including abuse in prison,8 intimidation of families,9 extended prison sentences for publishing controversial materials,10 forced shut down of blogs,11 detention to prevent participation in public protests,12 trials behind closed doors,13 and physical assault after posting controversial material.14 Blogger Paulus Le Son has been held without trial since his arrest in August 2011, following his coverage of the arrest of blogger Cu Huy Ha Vu.15 In August 2012, blogger Dinh Dang Dinh was sentenced to six years’ imprisonment following his posting of material that was critical of government corruption and an environmentally sensitive mining project.16 Three prominent bloggers, Dieu Cay, Phan Thanh Hai, and Ta Phong Tan, saw their trial delayed in July 2012 following the death by self-immolation of Tan’s mother.17 The combination of judicial and extra-judicial action against bloggers with new regulations that would further limit and criminalize the posting of critical content online serve to increase the dangers faced by bloggers operating in Vietnam.

Previous ONI testing in Vietnam

ONI conducts technical testing of Internet filtering using specially designed software distributed to researchers located in the country of interest.18 ONI has conducted three prior phases of testing for Internet filtering in Vietnam, in 2005, 2007 and 2010. All three periods of testing, which in total tested three of the country’s largest Internet Service Providers (ISPs), documented evidence of Internet filtering. In all cases, most of the content found filtered was in Vietnamese and related to sensitive political topics in the country. This filtered content included material critical of the Vietnamese Communist Party and content relating to the country’s human rights situation, indigenous peoples and religious groups. In addition, Internet circumvention and anonymization tools were also found to be blocked.

  • Testing conducted in 2005 on the ISPs Financing and Promoting Technology Corporation (FPT) Telecom and Vietnam Posts and Telecommunications Group (VNPT) found that the majority of sites blocked within the testing sample were Vietnamese-language sites and related to sensitive political issues in the country.
  • In 2007, tests conducted on FPT and VNPT found that the majority of blocked content was again specific to Vietnam, including the Vietnamese-language version of Radio Free Asia (, content relating to local communities (;, and sites containing strong anti-Communist views (; Although most of the content found blocked related specifically to Vietnam and was in Vietnamese, there were exceptions, such as the English-language version of Radio Free Asia ( and the website of international NGO Human Rights Watch (
  • Testing conducted in 2010 on FPT Telecom and Viettel found similar trends in filtered content. While evidence of filtering was found in all categories that ONI tests, the majority of content found filtered was Vietnamese-language content critical of the Vietnamese Communist Party. Websites found blocked included those advocating political reform (such as and as well as internationally-based news sites such as the Vietnam Daily News (, Huó’ng Du’ó’ng (, and Vietmedia ( Human Rights Watch remained the only website of an international human rights group that was blocked. Also found blocked were Facebook and sites dedicated to tools used to circumvent Internet filtering.

All testing periods found inconsistencies in the level of filtering between ISPs, in both the breadth and depth of content filtered. No ISP was found to block pornographic content, despite this being a stated justification for Internet censorship. Finally, with the exception of 2005 testing on VNPT, all ISPs in the country were found to filter through DNS tampering. This method of filtering returns inaccurate IP address information during the domain name resolution process, rendering the website inaccessible in a manner that is not transparent to users about what content is blocked.19 Despite the lack of transparency, DNS tampering is often straightforward to bypass, and circumvention methods are well documented by the Vietnamese Internet community.20

2012 ONI testing results

ONI conducted testing between April and August 2012 on three Vietnamese ISPs: VNPT, Viettel, and FPT Telecom. Two lists of URLs were tested: a ‘global list’ of internationally relevant and popular websites, and a ‘local list’ of content specific to Vietnam’s political and social context. The global list consisted of 1,124 URLS, while the local list contained 322 URLs, for a total of 1,446 URLs. Each ISP was tested at least three times over the testing period.

The results of testing in 2012 were similar to previous rounds of ONI testing in the country, with filtering primarily targeting critical political content and news sites related to Vietnam, as well as online censorship circumvention tools. As in past testing, filtering was not consistently applied across ISPs, with Viettel found to block more content than both VNPT and FPT. Of the sample of 1,446 URLs tested, Viettel was found to block 160 URLs, FPT was found to block 121 URLs, and VNPT was found to block 77 URLs.

Figure 1 – Side-by-side comparison of header results from VNPT (“Field Results”) and control case (“Lab Results”) for an attempt to access Note DNS resolution of fromVNPT.

(Click image to enlarge)
Figure 1 - Side-by-side comparison of header results from VNPT (“Field Results”) and control case (“Lab Results”) for an attempt to access

Figure 2 – Side-by-side comparison of header results from Viettel (“Field Results”) and control case (“Lab Results”) for an attempt to access

(Click image to enlarge)

The three ISPs were found to block similar types of content, and there was significant overlap in many of the sites found to be blocked. In general, the majority of content found blocked on all three ISPs was Vietnam-specific, including critical political blogs, news sites, and sites of domestic and international NGOs. Some non-Vietnamese content was found to be blocked on all three, including sites of anonymization and circumvention tools and web-hosting services.

A number of websites associated with imprisoned bloggers were also found blocked. The blog of Paulus Le Son ( was found blocked on Viettel and VNPT. Independent news site Dan Chim Viet (, for which imprisoned blogger Lu Van Bay had written, was blocked on Viettel and FPT. Vietnam Redemptorist News (, a site that had featured contributions from arrested bloggers Dang Xuan Dieu, Ho Duc Hoa, and Nguyen Van Duyet, was found blocked on Viettel and FPT. Environmental blog Bauxite Vietnam (, for which imprisoned blogger Nong Hung Anh wrote, was found blocked on FPT and Viettel.

All three ISPs blocked websites related to the Montagnard indigenous peoples (such as and, as well as Vietnamese news sites (e.g., and and sites belonging to Vietnamese political organizations (e.g., and

Blocking, however, was not entirely consistent across ISPs. As already mentioned, Viettel was found to block the greatest number of URLs of the three ISPs tested. It generally blocked Vietnam-related political and news content, as well as some content hosting services ( and and U.S. military websites. Viettel blocked a number of political blogs (including,,,, and and religious sites (such as and, as well as a number of international news sites (,, and and NGO sites ( and

FPT was found to block fewer total URLs than Viettel, although it blocked similar types of content. The vast majority of sites found blocked on FPT were also blocked on Viettel. VNPT was found to block the fewest URLs of the three ISPs tested. The type of content found to be filtered was similar to the other two ISPs; notably, however, it was the only one of the three found to block access to Facebook. VNPT was also found to block a number of critical political blogs (such as,, and which were not found to be blocked on Viettel or FPT.

It is not clear why such variation in filtering exists between ISPs, a finding that has been consistent across all phases of ONI testing. Both Viettel and VNPT are state-owned enterprises, with Viettel operated by the military, while FPT is privately owned. However this alone does not explain the variation as VNPT was found to filter fewer total URLs than FPT. The relatively small number of URLs found to be blocked on all three ISPs suggests that they do not share a common list of URLs to block.


Vietnam remains a heavily restricted information space, with a consistently strict Internet filtering regime and ongoing targeting of critical bloggers. The introduction of regulations that would provide new powers to censor and criminalize Internet use threatens Vietnam’s information space even further. The ongoing harassment, intimidation, and detainment of bloggers, combined with the potential for new real-name registration requirements, make Vietnam a dangerous environment in which to express dissent.


The OpenNet Initiative would like to thank Trinh Nguyen (Viet Tan) and Human Rights Watch for contextual research assistance. We would also like to thank an anonymous tester for generous assistance in collecting data from Vietnam.


The complete list of blocked URLs, as well as the lists of URLs tested, can be found here:

  • Complete list of blocked sites on all ISPs tested
  • Viettel blocked URLs
    • [CSV] [Google Doc]
    • Testing conducted April 24th to June 26th, 2012
  • FPT Telecom blocked URLs
    • [CSV] [Google Doc]
    • Testing conducted from April 19th to August 2nd, 2012
  • Vietnam Post and Telecommunications Group (VNPT) blocked URLs
    • [CSV] [Google Doc]
    • Testing conducted from April 13th to June 11th, 2012
  • List of URLs tested in Vietnam

Important note about testing data: The absence of a particular URL from any of the lists of blocked URLs is not necessarily an indication that the content is accessible in Vietnam. In some circumstances, issues encountered during data collection prevent the confirmation of the status of a given URL.


1Ministry of Information and Communications of the Socialist Republic of Vietnam, “Draft Decree management, supply and use of internet services and information content on the Internet,” April 18, 2012,

2Human Rights Watch, “Vietnam: Clinton should spotlight Internet freedom,” July 9, 2012,

3Radio Free Asia, “Vietnam drafts new online censorship rules,” April 11, 2012,

4Duy Hoang, Angelina Huynh, Trinh Nguyen, “Vietnamese authorities mandate Google, Facebook and other Internet companies to assist in online censorship,” April 11, 2012,

5Global Network Initiative, “Global Network Initiative concerned by government of Vietnam’s proposed Internet decree,” May 23, 2012,

6Reporters without Borders, “Draft decree would end online anonymity, force foreign Internet firms to censor,” April 13, 2012,42312.html; Article 19, “Vietnam: Internet decree of Internet-phobia?” June 21, 2012,; Radio Free Asia, “Internet draft decree slammed,” June 7, 2012,

7Deibert, R., Palfrey, J. G., Rohozinski, R., & Zittrain, J. (Eds.). (2011). Vietnam. In Access Contested: Security, Identity, and Resistance in Asian Cyberspace (pp. 385–397). Cambridge, MA: MIT Press.

8Radio Free Asia, “Jailed blogger ‘loses arm’”, July 27, 2011,

9Radio Free Asia, “Vietnamese blogger family harassed,” December 4, 2011,

10Radio Free Asia, “Bloggers face further imprisonment,” April 16, 2012,

11Radio Free Asia, “Authorities shutter land dispute blog,” June 13, 2012,

12Radio Free Asia, “Authorities target bloggers at protests,” July 2, 2012,

13World Organization Against Torture, “Viet Nam: Pro-democracy bloggers face harsh penalties in upcoming trial,” August 1, 2012,

14Radio Free Asia, “Blogger slashed by thugs,” July 11, 2012,

15Reporters Without Borders, “Blogger Paulus Le Son arrested again amid mounting tension,” August 4, 2011,,40751.html

16Radio Free Asia, “Dissident blogger jailed,” August 9, 2012,

17Radio Free Asia, “Bloggers’ trial put off,” August 3, 2012,

18For more information on ONI’s testing methodology, see

19For more information about methods of filtering, see Murdoch, S. J., & Anderson, R. (2008). Tools and technology of Internet filtering. In R. Deibert, J. G. Palfrey, R. Rohozinski, & J. Zittrain (Eds.), Access Denied: The Practice and Policy of Global Internet Filtering (pp. 57–72). MIT Press.

20Nguyễn Vũ Hưng: open source blog, “Bypass Facebook filtering in Vietnam,” December 14, 2011, ; Saigonist, “Bypass Vietnam’s block on Facebook – or China’s block on YouTube,” January 4, 2011,