Ethiopia: Evidence of social media blocking and internet censorship
Maria Xynou (OONI), Arturo Filastò (OONI), Amnesty International, Girma Walabuma
2016-12-14
Youth in Addis trying to get Wi-Fi Connection. Credit Addis Fortune Newspaper
Recently we published a post about what appeared to be a possible internet
shutdown in Ethiopia during a wave of ongoing protests by ethnic groups. Today,
in collaboration with Amnesty International we are releasing a report that
includes evidence of recent censorship events during Ethiopia’s political
upheaval.
See the Amharic translation of the report. Translated by Wolete Mariam.
View the pdf version of the report here.
Country: Ethiopia
Probed ISP: EthioNet-AS, ET ( AS24757 )
Censorship method: Deep Packet Inspection (DPI), HTTP response failures, DNS
tampering, TCP injections
OONI tests: Web Connectivity, Vanilla Tor, WhatsApp test, HTTP invalid request
line, HTTP header field manipulation, HTTP Host
Measurement period: 2016-06-15 - 2016-10-07
Key Findings
New OONI data published in this report reveals the following:
WhatsApp was found to be blocked inside Ethiopia.
Deep Packet Inspection (DPI) technology was detected. DPI is technology that
can be bought and deployed on any network, enabling monitoring and filtering of
Internet traffic. This can be useful as part of network management, but it can
also be used for mass surveillance and internet censorship. This finding
suggests that Ethiopia has DPI technology in its possession and is deploying it
for censorship purposes inside the country.
Out of 1,403 different types of URLs that were tested, the types of sites that
consistently presented network anomalies and which were more likely to be
blocked include:
News outlets and online forums
Armed groups and political opposition websites
LGBTI websites
Websites advocating free expression
Circumvention tool websites (including Tor and Psiphon)
The above types of websites mostly presented HTTP response failures, indicating
that they were likely blocked by DPI equipment. Overall, 16 different Ethiopian
news outlets presented signs of censorship, many of which showed evidence of
being blocked prior to the state of emergency declaration.
In the course of this investigation, OONI also sought to verify reports from
Ethiopia of a mobile internet shutdown in October 2016. OONI software tests are
designed to examine the blocking of sites and services, but do not monitor
internet shutdowns as a whole. As such, the organisation referred to third party
data such as Network Diagnostic Test (NDT) measurements and Google transparency
reports, in an attempt to examine whether the reported internet shutdown could
be confirmed.
The below graph from Google’s transparency reports illustrates the total volume
of Google Search traffic originating from Ethiopia between July and November
2016. As published in an earlier report by OONI and Strathmore University Centre
for Intellectual Property and Information Technology Law (CIPIT), the data shows
a complete drop in Internet traffic in early August, suggesting that a full
Internet block took place following the call by political activists for region-
wide protests on the weekend of 5 and 6 August. While the data shows a decrease
in internet traffic during October, there is no strong indication of an internet
shutdown along the lines of that observed in early August.
Google Transparency Report, Ethiopia, Google Search traffic between July and November 2016.
The findings suggest that if an internet shutdown did occur in October, it only
occurred in some networks in certain locations, rather than nationwide.
Furthermore, the decrease in overall traffic during October could be attributed
to temporary mobile internet shutdowns in certain local networks, or to an
increase of censorship events (for example, targeted blocking of certain
websites and instant messaging services). An examination of data from the
circumvention software Tor, shows a spike in traffic from Ethiopia in October,
suggesting that more people were seeking ways around censorship. This indicates
that there might have been an increase in censorship events following the
declaration of Ethiopia’s state of emergency.
OONI was unable to confirm the reported mobile internet shutdown in October,
partly due to limitations in NDT measurements and Google transparency reports.
We therefore strongly encourage Internet companies including Facebook,
Microsoft, Yahoo and Twitter, to increase transparency around internet traffic
data so that internet shutdowns and other censorship events can be investigated
and verified quickly, and more accurately.
Many of these acts of censorship took place before a state of emergency was
announced, raising questions about whether these measures had any basis in
Ethiopian law, as required by international human rights law. While the State of
Emergency may have subsequently provided a legal framework under Ethiopian law
for some of these measures, the State of Emergency itself is so broadly drafted
that it violates Ethiopia’s international legal obligations and permits
violations of numerous human rights. Amnesty International and OONI are
concerned that unnecessary and disproportionate censorship of the internet will
not only continue during the state of emergency, but become institutionalized
and entrenched.
OONI has unearthed evidence of systematic interference with access to numerous
websites belonging to independent news organizations and political opposition
groups, as well as sites supporting freedom of expression and LGBTI rights. Such
widespread interference and blocking is a violation of people’s freedom of
expression, and specifically, people’s right to hold opinions without
interference, and their right to receive and impart information of all kinds as
guaranteed under article 19 (1) and (2) of the International Covenant on Civil
and Political Rights (ICCPR), which Ethiopia has ratified.
Ethiopia’s position on the use of social media indicates that the authorities
are invoking their obligations to restrict freedom of expression where such
freedom is abused, as articulated in article 19 (3) of the ICCPR. However, the
acts of censorship uncovered by OONI’s study are inconsistent with the
requirements laid out in the ICCPR to restrict these rights. Specifically, that
any restrictions will be provided by law and are necessary to respect the rights
or reputations of others; or for the protection of national security or of
public order, public health or morals. Any restrictions to freedom of expression
is subject to a three part test: that they are legal; necessary and
proportional. The acts of censorship evidenced in OONI’s study fail to meet the
test. They are arbitrary, being carried out in the absence of clear and precise
law in the country which governs access to internet and social media,
restrictions/blockade of websites and social media, and clear legal procedures
governing restrictions, including administrative and judicial procedures to
challenge such restrictions and blockades. The acts of censorship also fail the
test of proportionality. The censorship acts uncovered by OONI were not
restricted to specific content; rather the censorship was happening at a large
scale, with dozens of websites and popular communications platforms like
WhatsApp affected over the space of several months.
The decision to restrict people’s ability to receive and impart information by
censoring internet access during the protests, only served to sweep the
underlying issues fuelling the protests under the carpet. To fully address the
situation that led up to the state of emergency, the government must genuinely
commit to addressing the underlying human rights violations that triggered the
protests in the first place; and respect its human rights obligations. This
includes refraining from blocking access to the internet and ensuring that all
its people can enjoy their right to express their opinions; even those who
criticise government policy and action; and guarantee their right to expression
and association online and offline.
Social media companies should make available publicly verifiable data on network
traffic originating from countries around the world, to ensure transparency when
social media restrictions or heavy network disruptions occur.
Executive Summary
Waves of protests against the government have taken place across various parts
of Ethiopia since November 2015. These protests have consistently been quashed
by Ethiopian security forces using excessive, sometimes lethal, force, which led
to scores of injuries and deaths. The crackdown on protests was accompanied by
increasingly severe restrictions on access to information and communications in
large parts of the country by cutting off internet access, slowing down
connections and blocking social media websites.
The protests began on 12 November 2015 in Ginchi, a town in West Shewa Zone of
Oromia Region, against the Addis Ababa Masterplan, a government plan to extend
the capital Addis Ababa’s administrative control into parts of the Oromia. The
protests continued even after the Government announced in January that they had
cancelled the plans, and later expanded into the Amhara region with demands for
an end to arbitrary arrests and ethnic marginalization.
Amnesty International’s research since the protests began revealed that security
forces responded with excessive and lethal force in their efforts to quell the
protests. Amnesty International interviewed at least fifty victims and witnesses
of human rights abuses during the protests, twenty human rights monitors,
activists and legal practitioners within Ethiopia, and also reviewed relevant
other primary and secondary information on the protests and the government
response. Based on this research, the organisation estimates that at least 800
people have been killed since the protests began.
Tensions in Oromia escalated at the beginning of October, following a stampede
during a religious festival which killed at least 55 people. Fresh protests,
some of which turned violent, broke out amidst contestations over who was
responsible for the stampede. Oromo activists blamed security forces for firing
live ammunition and tear gas into the crowds, while the government blamed anti-
peace protestors. The government of Ethiopia declared a state of emergency on 8
October. The state of emergency imposes broad restrictions on a range of human
rights, some of which are non-derogable rights, meaning that under international
law, they may never be restricted, even during a state of emergency.
In addition to using security forces to quash protests, the Ethiopian
authorities have restricted access to internet services during this time.
Amnesty International´s contacts inside Ethiopia reported that social media and
messaging mobile applications such as Facebook, WhatsApp and Twitter, have been
largely inaccessible since early March 2016, especially in the Oromia region
where the bulk of the protests were taking place. Internet services were also
completely blocked in Amhara, Addis Ababa and Oromia Regions following a call by
political activists for region-wide protests on the weekend of 6 and 7 August
2016. The protests went ahead during these two days. The government security
forces used excessive force against the protesters in Addis Ababa, Amhara and
Oromia Regions resulting in the death of at least 100 people.
Internet disruptions started again on 5 October 2016 after protesters in some
parts of Oromia targeted businesses, investments, government buildings and
security forces in the wake of the stampede during the Irrecha thanksgiving
festival in Oromo, which killed at least 55 people. Amnesty International´s
contacts have since reported that internet connections were very slow and social
media services have been inaccessible through browsers. Access to the mobile
internet connection in Addis Ababa improved for a couple of days in early
December, on 4th and 5th, before becoming inaccessible once again.
The Ethiopian government considers that social media has empowered populists and
extremists to exploit people’s genuine concerns and to spread bigotry and hate.
This position was made clear in the Prime Minister’s speech to the UN General
Assembly in September. Indeed, a number of political and other activists have
been arrested and charged under the Anti-Terrorism Proclamation on the basis of
their activities on social media platforms. Yonatan Tesfaye, formerly of the
Blue Party, was arrested and charged with terrorism crimes because of his
facebook posts criticizing government policy and action.
In the midst of these protests, and in response to the numerous reports from
Ethiopia that access to the internet was being blocked, the Open Observatory of
Network Interference (OONI) performed a study of internet censorship. OONI is a
free software project whose goal is to increase transparency about internet
censorship and traffic manipulation around the world. OONI undertook the study
in order to assess whether, and to what extent the censorship being reported
actually occurred during the protests. OONI sought evidence of websites and
instant messaging apps were being blocked; systems causing censorship and
traffic manipulation; and inaccessibility of censorship circumvention tools such
as Tor and Psiphon.
OONI’s software tests were run from a computer inside the country (running on
the EthioNet network, the Ethiopia telecom monopoly). Tests were run on a total
of 1,403 different URLs, including both Ethiopian and global websites, in order
to determine website blocking. Additional OONI tests were run to examine whether
systems that could be responsible for censorship, surveillance, and traffic
manipulation were present in the tested network. OONI then processed and
analysed the network data collected based on a set of criteria for detecting
internet censorship and traffic manipulation. The testing period started on 15
June 2016 and concluded on 7 October 2016, immediately prior to the announcement
of the state of emergency.
This report, presents the findings of the OONI study, and Amnesty
International’s human rights analysis of these findings. This report also
provides details of the technical methodology OONI used to verify the blockade
on Whatsapp and the restrictions on websites with political and other content in
a second, distinct section.
Methodology
This report has two distinct sections. Part 1 of the report presents Amnesty
International and OONI´s joint findings related to Internet censorship during
the protests that have rocked Ethiopia since November 2015. Part 2 of the report
provides a detailed overview of OONI´s technical study, including the full range
of tests performed on Ethiopia´s network and acknowledged limitations in the
methodology.
Amnesty International has been documenting the protests since they began, as
well as the state response to the same. Primarily, Amnesty International has
conducted this research remotely, relying on victim and eyewitness testimony,
which has been taken through at least 50 phone and email interviews. Amnesty
International researchers have also used a variety of other primary and
secondary information to corroborate and verify witness accounts of specific
incidents including at least 20 phone and email interviews with human rights
monitors in Ethiopia; members of Ethiopian political opposition parties
including spokespersons; media reports; reports and images posted on social
media; and Ethiopian government communications. Amnesty International has tried
unsuccessfully to engage with the Ethiopian authorities on the protests.
The information gathered by Amnesty International and used in this report, is to
provide the background, and context within which the OONI network measurement
study was carried out. It is not intended to provide comprehensive information
on the human rights violations that have occurred in the context of the
protests. For more information and analysis on the protests, please visit
Amnesty International’s website.
The Open Observatory of Network Interference (OONI) is a free software project
that aims to increase transparency about internet censorship and traffic
manipulation around the world. OONI undertook a network measurement study, which
run from 15 June to 7 October 2016. OONI used multiple free and open source
software tests it had designed to examine the following:
Blocking of websites and instant messaging apps.
Detection of systems responsible for censorship and traffic manipulation.
Reachability of circumvention tools (such as Tor, Psiphon, and Lantern) and
sensitive domains.
It is important to note that the technical findings are subject to limitations,
and do not necessarily reflect a comprehensive view of internet censorship in
Ethiopia. The methodology, and its limitations, are discussed in detail in part
2 of the report.
Part 1: Evidence of internet censorship
Background: Sustained protests
Despite the lack of confirmed data about casualties, an estimated 800 people
have been killed due to excessive or otherwise unlawful use of force by the
security forces - some of which may amount to extrajudicial executions - since
the beginning of the protests in November 2015. The United Nations High
Commissioner for Human Rights has described the situation as “extremely
alarming” and urged Ethiopia to allow international human rights observers into
the country. The Ethiopian government, however, rejected this UN request,
arguing that it alone is responsible for the security of its citizens.
There have been almost continuous protests in parts of Ethiopia since November
2015. The protests in Oromia region were initially triggered by plans to extend
the capital, Addis Ababa, into Oromia, but continued even after the Addis Ababa
Masterplan was scrapped in January, evolving into demands for accountability for
human rights violations, ethnic equality and the release of political prisoners.
In August 2016, people in the Amhara Region joined protests against arbitrary
detention of members of the Wolkait Amhara Identity and Self-determination
Committee. The Ethiopian security forces have consistently used excessive, including lethal, force to disperse the protesters. Over 600 protesters in
Oromia and 200 in Amhara have been killed as a result. Hundreds of political
activists, human rights defenders, journalists and protesters have been
arrested. Since the start of the protests in November last year, the police have
charged at least 200 people, including journalists, bloggers and opposition
political party leaders, under the Anti-Terrorism Proclamation. Their trials
were ongoing as of November 2016.
Tensions in Oromia escalated again following a stampede during the Irrecha
religious festival on 2 October that resulted in the death of at least 52 people. The cause of the stampede, and the number of casualties, is contested.
The government has claimed that protesters triggered the stampede, while Oromo
activists claim that the government security forces caused the stampede when
they fired tear gas canisters and shot live ammunition into the crowds.
Following the stampede, fresh protests broke out in Oromia with a number of them
turning violent. Protesters attacked foreign and local businesses, farms, and
vehicles, especially those near Addis Ababa.
In response to the wave of protests, the government of Ethiopia severely
restricted internet access and declared a state of emergency on 8 October 2016.
The state of emergency imposes broad restrictions on a variety of human rights,
some of which are non-derogable rights, meaning that under international law,
they may never be restricted, even during a state of emergency. The arrest and
detention of protesters and politically-outspoken individuals critical of
government action continues, including Zone-9 bloggers Natnael Feleke on 4
October and Befeqadu Hailu on 11 November. The government forces also arrested
Anania Sorri and Daniel Shibeshi (members of former Unity Party) and Elias Gebru
(journalist) on 18 November 2016. The three of them had posted their picture
showing the protest sign on 28 October 2016.
The Government of Ethiopia continues to accuse the Ethiopian diaspora based
opposition political parties, Egypt and Eritrea for supporting and fostering the
protests.
Internet censorship during protests
Testimonies gathered by Amnesty International from different parts of the Oromia
region indicate that social media mobile applications such as Facebook,
WhatsApp, and Twitter, were largely inaccessible since early March 2016,
especially in the Oromia region, where residents were waging protests against
the government since November 2015.
"…you can’t use social media apps across Oromia for the last 6 weeks[since Mid-
March]. I personally checked it in Ambo town in West Shawa Zone and In
Batu/Ziway in East Shawa Zone and all [along] the road to there. The blackout is
directed to the apps [both Android and IOS] but, the whole Internet is too slow
and not working at all in some parts of the Region."
Moreover, the witnesses Amnesty International spoke to in the Oromia region and
neighbouring cities, such as Hawassa, said that not only are the popular social
media applications largely inaccessible, but that the internet has also been
rendered unusually slow.
“All the way to Hawassa from Addis Ababa, I was not able to access skype and
facebook. Even after I reached Hawassa, the connection was too slow that I was
not able to have decent skype conversation during the night.”
The Government blocked access to Facebook, Instagram, Twitter and Viber during
the National University Exam week “to prevent students being distracted from studying during the exam period and to prevent the spread of false rumours”.
Accordingly, those social media outlets were reportedly inaccessible throughout
the country from 9-14 July 2016.
Internet services were also reportedly not available in Amhara, Addis Ababa and
Oromia Regions following the call for region-wide protests on the weekend of 6
and 7 August 2016. During these two days, the government used excessive,
including lethal force against protesters in Addis Ababa, Amhara and Oromia
Regions resulting in the death of at least 100 people.
Social media and mobile internet was also reportedly unavailable from 5 October
2016 after protests in some parts of Oromia targeted businesses, investments,
government buildings and security forces, during a proclaimed “week of rage”.
In addition, the government employed legislative and judicial tools to
discourage the use of internet and social media for expression of dissenting
views. The government passed a new computer crimes law in June 2016 that among
other things penalises distribution of “violent messages, audio, or video”. The
law also authorizes the Ministry of Justice to issue a warrant for interception
or surveillance, and people suspected of computer crimes can be held in pre-
trial detention for up to four months. The law has had a chilling effect on the
flow of information about human rights violations perpetrated by the security
forces against protesters.
The Ethiopian government has relied on the Anti-terrorism Proclamation (ATP) to
charge and convict people who have criticized government policy and action on
social media platforms. The Ethiopian Government arrested and charged Yonatan
Tesfaye, a political activist and former public relation head of the Blue Party,
with terrorism crimes under the ATP because of the content of his posts on
Facebook. The Zone-9 bloggers and Zelalem Workalemahu et el were also tried
because of their online activities. The Prosecutor charged the Zone-9 bloggers
with terrorism crimes for using encrypted software to ensure the security of
their communications. In Zelalem Workalemahu et al the Court convicted the first
defendant, Zelalem Workalemahu, for provision of training on online encryption
methods.
The Ethiopian Prime Minister´s speech at the United Nations General Assembly in
September 2016, gave an indication of the government’s views around the use of
social media: “social media has certainly empowered populists and other
extremists to exploit people’s genuine concerns and spread their message of hate
and bigotry without any inhibition."
It is unlikely that social media played a crucial role in mobilizing the
protests, given that internet penetration in the country remains very low at
2.9%. However, it has aided protesters in uncovering acts of violence committed
by the security forces. Previous protests in the country, such as the April 2014 Oromo Protest against the Addis Ababa Master Plan and the Muslim protest against
government interference in religious affairs since 2012 did not attract
international media coverage. However, the current protests in Oromia and Amhara
Regional States have gained a relatively greater media coverage due to the use of social media, even in very small towns, where witnesses have reported on
events and the violence committed by the security forces, sometimes in real-
time. For instance, the footage from the Irrecha tragedy on 2 October 2016 was
available on social media platforms almost in real time.
Google traffic data depicts an acute decline of traffic on 6 and 7 August 2016,
when there was a call by political activists for protests in Addis Ababa,
Oromia, and Amhara. The internet shutdown tallied with the heavy-handed response
of the security forces to the protests on these dates. Since social media was
not accessible on those days in Amhara, Oromia and Addis Ababa there were very
little reports at the time of the violence by the security forces. It was only
after 8 August 2016 that pictures, footage, and reports of excessive force by
security forces started to emerge on social media.
State of emergency
Ethiopia is currently in a state of emergency for six months, as announced by
the government on 8 October 2016.
The Government has arrested more than 11,000 people for “violence and property
damage". Amongst those in detention are bloggers, journalists, and members of the
political opposition, for publicly criticizing the government, the state of
emergency declaration or for posting the protest sign on Facebook.
Under the state of emergency, all unauthorized protests and assemblies are
banned. Sharing information about protests through social media platforms, such
as Facebook and Twitter, is prohibited, while two TV stations run for the
Ethiopian diaspora, ESAT and the Oromia Media Network, are banned due to their
coverage of the protests.
The state of emergency declaration imposes broad derogations on a variety of
human rights, some of which affect non-derogable rights according to Article 4
(3) of the International Covenant on Civil and Political Rights (ICCPR). The
state of emergency declaration established a Command Post chaired by the Prime
Minister with the power to determine the specific restrictions, measures, and
geographic scope in the implementation of the state of emergency.
The Command Post has broad powers, including to:
Prohibit any overt or covert incitement for violence or ethnic conflict, in
whatever form of expression;
Stop or suspend any media;
Prohibit any assembly, association and demonstration;
Arrest anyone suspected of using violence in the areas the Command Post
identifies. Those arrested will be educated and released and, if necessary, they
will be punished under relevant law;
Search and seize any person or place and confiscate where necessary;
Impose curfew;
Block any road or public place or evacuate and move people from certain places;
Evacuate people vulnerable to threats and keep them in safe places for a limited
period of time;
Use proportionate force necessary for the implementation of the state of
emergency;
Accordingly, the Command Post issued a Directive on 15th October, which further
enumerated the acts prohibited, the state of emergency measures, and the
obligations to keep and communicate records. The directive conferred the
security forces with the powers to:
Arrest without warrant;
Detain those arrested at places designated by the Command Post until the end of
the state of emergency;
Search without warrant anytime and anywhere;
Monitor and control any messages through radio, TV, articles, pictures,
photographs, theatre and movies.
Sources told Amnesty International that the security forces have demolished a
number of private satellite frequency receivers in the Oromia and Amhara
regions, barring access to the broadcasts of the Ethiopian Satellite Television
and Oromia Media Network. Several witnesses have also told Amnesty International
that they were unable to access mobile internet service in Oromia, Addis Ababa,
and Amhara Regional States resulting in information blackout on the human rights
situation in those regions. However, it is not clear why the mobile internet was
unavailable.
Findings of the network measurement study
The Open Observatory of Network Interference (OONI) performed a study of
internet censorship in Ethiopia in the midst of tensions and ongoing public
protests in Oromia region, and prior to the announcement of the country’s state
of emergency. The aim of this study was to understand whether and to what extent
the censorship being reported actually occurred during the protests, and to
provide evidence in relation to:
Blocking of websites and instant messaging apps
Detection of systems responsible for censorship and traffic manipulation.
Reachability of common circumvention tools used to get around censorship (such
as Tor and Psiphon).
OONI’s software tests were run from a computer inside
the country (running on the EthioNet network, the Ethiopia telecom monopoly).
Tests were run on a total of 1,403 different URLs, including Ethiopian websites
as well as URLs that are commonly accessed around the world. All URLs were
tested for blocking. Other OONI tests were run to examine whether systems that
could be responsible for censorship, surveillance, and traffic manipulation were
present in the tested network. OONI processed and analysed the network
measurement data collected from these tests based on a set of heuristics for
detecting internet censorship and traffic manipulation.
The testing period started on 15 June 2016 and concluded on 7 October,
immediately prior to the announcement of the state of emergency. The testing was
also limited due to security risks to people involved in conducting the testing.
Even though Ethio Telecom is government owned and Ethiopia’s main ISP, it is
likely that censorship was implemented differently across locations, and that
the findings of this study do not necessarily represent nationwide censorship. A
detailed explanation of the methodology, including limitations, can be found in
part 2 of this report.
WhatsApp blocked
OONI has designed a new software test for examining the reachability of
WhatsApp.
This test attempts to perform an HTTP GET request, TCP connection and DNS lookup
to WhatsApp’s endpoints, registration service and web version over the vantage
point of the user. Based on this methodology, WhatsApp’s app is likely blocked
if TCP/IP connections to its endpoints and/or registration service fail, if the
DNS lookup illustrates that different IP addresses have been allocated to its
endpoints, and/or if HTTP requests do not send back a response to OONI’s
servers. Similarly, WhatsApp’s website is likely blocked if any of the above
apply to web.whatsapp.com.
An anonymous researcher ran this test in October from a local vantage point in
Ethiopia (Ethio Telecom) in an attempt to examine whether and how WhatsApp was
censored. The collected measurement data illustrates that while both HTTP and
HTTPS requests to web.whatsapp.com succeeded, HTTPS requests to WhatsApp’s
registration service failed, and so did TCP connections to WhatsApp’s endpoints.
This indicates that WhatsApp’s website was accessible, but its app was blocked.
| web.whatsapp.com | WhatsApp endpoints | WhatsApp registration service |
---|
HTTP request | Success | - | - |
HTTPS request | Success | - | Failed |
TCP connection | - | Failed | - |
DNS lookup | Consistent | Consistent | Consistent |
Result | Accessible | Blocked | Blocked |
Deep Packet Inspection detected
An Ethiopian news website (ecadforum.com) was found to be blocked last month
based on the use of Deep Packet Inspection (DPI) technology. DPI enables its
users to analyze data packets and protocols. This can be useful as part of
network management, but it can also be used for data mining and internet
censorship.
The blocking of ecadforum.com by DPI equipment was uncovered through OONI’s HTTP host test which was run from a local vantage point in Ethiopia. This test
attempts to examine whether the domain names of websites are blocked, and to
detect the presence of “middle boxes” (software that could potentially be used
for censorship and/or traffic manipulation) in tested networks.
As part of our testing, we performed HTTP requests towards one of OONI’s control
servers. This server is responsive for just sending back any data it receives.
In absence of censorship equipment, we would be able to view OONI Probe’s
request. But when we sent the HTTP Host header containing the domain
“ecadforum.com” to our control server, we noticed that the connections would get
reset. We were only able to receive the control response when requesting a
subdomain of “ecadforum.com” and when we prefixed the request method (GET) with
the newline character. This is summarized in the table below:
| ecadforum.com |
---|
Normal GET request | Blocked |
Modified GET request | Not blocked |
GET request to subdomain | Not blocked |
GET request to domain + \t (tab character) | Not blocked |
Get request to XYZecadforum.comZYX | Not blocked |
This leads us to conclude that the devices implementing this type of
interception were in fact “smart” enough to understand the HTTP protocol and
could only implement blocking when they found the request to match what they
expected to be “valid” HTTP. Therefore, DPI equipment was most likely present in
the tested network and used to implement censorship.
It’s worth pointing out that technology with a similar pattern was previously
found in Turkmenistan in 2013, as reported by OONI.
Websites blocked
Today Ethiopia’s state of emergency imposes restrictions on media. Yet, as part
of our study numerous Ethiopian news outlets presented signs of DNS, HTTP, and TCP/IP blocking prior to the state of emergency declaration.
The table below illustrates the amount and types of network anomalies detected
when testing such sites.
In some cases, we tested different versions of the same sites to examine whether
censorship could potentially be circumvented. Earlier this year, for example, we
found Ugandan ISPs only blocking the HTTP versions of social media sites,
enabling users to access these sites over HTTPS. In this study we therefore
tested various versions of certain sites, such as both the HTTP and HTTPS
versions of oromiamedia.org. In all such cases however, access to these sites
presented signs of network interference, as illustrated in the table above.
Overall, 16 different Ethiopian news outlets presented signs of censorship. As
no block pages were detected, we cannot confirm any censorship events with
absolute certainty. However, the sites that presented the highest amount of
network anomalies are more likely to have actually been blocked, while those
with fewer network anomalies are less likely to have been tampered with. As
such, ecadforum.com - with the highest amount of network anomalies - was most
likely blocked by DPI equipment (as explained previously), while access to it
might have also been interfered with based on DNS tampering. On the other hand,
sites which presented fewer cases of network anomalies (such as satenaw.com) are
less likely to have been blocked, though this remains a possibility.
In any case, it’s interesting to see that out of the 1,403 different URLs (1,217
URLs in the “global list” and 186 URLs in the “Ethiopian list”) that were tested
for censorship as part of this study, access to these 16 Ethiopian news outlets
presented the highest levels of network anomalies, indicating that they were
most likely tampered with. These sites include oromiamedia.org, which is an
independent, nonpartisan, and nonprofit news enterprise that reports on Oromia,
one of the main regions that has been at the heart of the recent wave of
protests and political unrest.
Currently, access to ethsat.com is banned in Ethiopia under the
country’s new state of emergency restrictions. This website is run by the
Ethiopian diaspora, aims to “promote free press, democracy, respect for human
rights and the rule of law in Ethiopia” and also publishes in Amharic. However,
we tested access to this site prior to Ethiopia’s state of emergency declaration
and our findings show that it presented many network anomalies. Similarly to
ecadforum.com, access to ethsat.com presented high levels of HTTP interference,
indicating that it might have also been blocked by DPI equipment before it was
even officially banned.
An Amharic online forum (mereja.com) also presented high levels of HTTP
interference, and was possibly blocked by DPI as well. While the motivation
behind the blocking of news sites could potentially be attributed to the
dissemination of information around the protests, the potential blocking of an
Amharic forum might be attributed to intentions to block communication,
coordination and information dissemination amongst Amharic protesters.
Political opposition and armed groups
As part of our study we found the websites of Ethiopian armed groups and
political opposition groups to be tampered with. In the case of those related to
armed groups espousing violent opposition to the Ethiopian government,
censorship may fall within the permissible restrictions to freedom of expression
under international human rights law.
The table below summarizes our findings:
Ginbot 7 is a national political party and part of Ethiopia’s political
opposition. In 2009 the Ethiopian government accused Ginbot 7 of fostering a
coup attempt to overthrow the government, which Ginbot 7 denied. Ginbot 7 is one
of the proscribed organizations under the Anti-Terrorism Proclamation, which is
potentially why ginbot7.org was blocked. Through our testing we found that
access to this website presented a high amount of network anomalies. In
September 2016 we tested ginbot7.org by sending multiple HTTP GET requests to
access the site. In all cases however, we never received a response.
The Ethiopian People’s Revolutionary Party (EPRP) is a national political party
which was founded by the Ethiopian diaspora and which is currently headquartered
in the United States. During the 1970s Ethiopia’s then military government
declared open war (“Red Terror” campaign) against the EPRP and other political
opponents, resulting in the death of around 250,000 Ethiopians. Similar to
ginbot7.org, we found eprp.com inaccessible due to HTTP response failures as
part of our testing.
The Oromo Liberation Front (OLF) is a regional political party that was
established by Oromo nationalists in the early 1970s to promote self-
determination, and which was designated as a “terrorist organization” by
Ethiopia’s government. The Ethiopian People’s Patriotic Front (EPPF) is an armed
opposition group in north western Ethiopia that was originally founded to
overthrow the EPRDF regime. As part of our testing, the websites of both groups
appeared to be inaccessible due to HTTP response failures.
Similarly, the websites of two armed opposition groups, the Ogaden National Liberation Front (ONLF) and the Patriotic Ginbot 7 Movement for Unity and Democracy, also presented HTTP response failures as part of our testing. The
ONLF is an separatist armed group that is fighting for the independence of the
Ogaden region in eastern Ethiopia, bordering with Somalia. An Ogaden news website was also found to be inaccessible, as illustrated in the table of the
previous section of this report.
LGBTI websites
As part of OONI’s testing, access to sites supporting LGBTI rights appeared to
be tampered with since we did not receive HTTP responses when querying them.
These sites, and our research findings, are included in the table below:
The International Foundation for Gender Education (IFGE) is a US-based
educational organization that promotes acceptance for transgender people, while
samesexmarriage.ca is a Canadian site that promotes same-sex marriage. QueerNet
is a project of the Online Policy Group (a non-profit dedicated to online policy
research around digital rights issues) which provides free online services (such
as email hosting, websites, and mailing lists) for LGBTI communities.
Same-sex sexual activity is prohibited in Ethiopia under Article 629 of the
Criminal Code punishable up to fifteen years imprisonment. All three websites
appeared to be inaccessible in September 2016, but appeared to be accessible
when tested again in early October 2016.
Human rights websites
Two sites promoting freedom of speech and expression also presented signs of
network anomalies as part of our study.
Cyber Ethiopia is a Swiss-based non-profit organization that aims to promote
human rights in Ethiopia through programs and policy recommendations that uphold
freedom of speech and expression online. The Free Expression Policy Project is a
think tank on artistic and intellectual freedom. It provides research and
advocacy on free speech, copyright, and media democracy issues.
When querying cyberethiopia.com, we did not receive an HTTP response, indicating
that access to the site was blocked. Our results regarding fepproject.org are
different. When testing the site in June and October 2016, we were able to
successfully connect to it. However, all attempts to establish TCP connections
to the site during August and September 2016 failed and presented timeout
errors. It remains unclear if fepproject.org was intentionally blocked
throughout August and September 2016 based on TCP/IP blocking, or if connections
to the site failed due to transient network failures.
Amongst the many sites that presented HTTP response failures are the sites of
major censorship circumvention tools: Tor and Psiphon.
Tor is a free and open source network designed to provide anonymity to its users
by bouncing their communications across a distributed network of relays, thus
masking their real IP addresses and enabling them to circumvent censorship.
Psiphon is free and open source software that utilizes SSH, VPN, and HTTP proxy
technology to enable its users to circumvent censorship. Ultrasurf is freeware
that utilizes an HTTP proxy server to enable its users to bypass censorship.
Both torproject.org and ultrasurf.us appeared to be inaccessible between June
and October 2016 due to HTTP response failures, while psiphon.ca presented the
same failures from August 2016 onwards. The fact that all three sites presented
HTTP response failures and that http://ultrasurf.us, https://ultrasurf.us and
http://psiphon.ca appeared to be slightly more accessible than
http://www.ultrasurf.us and http://www.psiphon.ca indicate the presence of Deep
Packet Inspection (DPI) equipment in the tested network (as explained in the DPI
section of this report).
While toproject.org was found to be inaccessible, we did not find tor software itself being blocked in Ethiopia during the testing period.
Circumventing censorship
Organizations and companies hosting websites that may be blocked in Ethiopia can
consider hosting their websites on a Tor hidden service to hide its IP address
and prevent blocking. It is also recommended to add HTTPS to your site through
Let’s Encrypt.
Individuals seeking to access blocked websites may consider using the below
circumvention tools and services to get around blocks. Note: Under Anti-
terrorism Proclamation, use of digital security tools have been used in the past
to prosecute bloggers and activists, even if there is no provision of law that
outlaws use of internet security tools, including tor. Yet It is vital that you
understand the security risks in accessing such tools.
Use Tor Browser (or other circumvention tools) to circumvent censorship and
access blocked sites.
If torproject.org is blocked, download Tor Browser here.
If the Tor network is blocked, get Tor bridges to circumvent the blocking and
connect to it.
Use the VPN mode of Orbot to access WhatsApp (and other IM apps) on Android over
the Tor network.
Internet shutdown?
Numerous reports surfaced in October regarding a mobile internet shutdown in
Ethiopia, and this was also reported to Amnesty International by contacts on
the ground.
OONI software tests are designed to examine the blocking of sites and services,
but do not monitor internet shutdowns as a whole. As such, we referred to third
party data such as NDT measurements and Google transparency reports in order to
assess whether we could confirm the reported internet shutdown.
The below graph from Google’s transparency reports illustrates the total volume
of Google Search traffic originating from Ethiopia between July and November
2016. As published in an earlier report by OONI, the data shows a complete drop
in Internet traffic in early August, suggesting that a full Internet block took
place following the call for region-wide protests on the weekend of 5 and 6
August. While the data shows a decrease in internet traffic during October,
there is no strong indication of an internet shutdown along the lines of that
observed in early August.
Google Transparency Report, Ethiopia, Google Search traffic between July and November 2016.
As Google Maps is another Google service that is commonly used via mobile
phones, we also looked at Google Maps traffic originating from Ethiopia between
July and November 2016.
Google Transparency Report, Ethiopia, Google Maps traffic between July and November 2016.
Similar to Google Search traffic, Google Maps traffic appears to be disrupted in
August but not in October. The above graphs indicate that if an internet
shutdown did occur in October, it only occurred in some networks in certain
locations, rather than nationwide. Furthermore, the decrease in overall traffic
during October could be attributed to temporary mobile internet shutdowns in
certain local networks, or to an increase of censorship events (for example,
targeted blocking of certain websites and instant messaging services).
Interestingly, there appears to be a spike in the usage of Tor circumvention software in Ethiopia during October, indicating that internet services might
have been less accessible. This is illustrated via Tor Metrics data below:
The graph below shows an increase in Tor usage from 8th October, when Ethiopia’s
state of emergency was declared.
Tor Metrics data, combined with third party internet traffic data, indicates a
possible increase in censorship events following the declaration of Ethiopia’s state of emergency. While there is no strong indication of an internet shutdown,
it is possible that certain mobile data service might have temporarily been shut
down in certain locations in Ethiopia at specific points in time.
It is worth noting that OONI’s inability to confirm the reported mobile internet
shutdown might also in part be due to limitations in the data sources that we
referred to. We therefore encourage companies (like Facebook) to increase
transparency around internet traffic data so that internet shutdowns and other
censorship events can be studied and evaluated more accurately.
International Human Rights Law
The International Covenant on Civil and Political Rights (ICCPR), to which
Ethiopia is a state party, guarantees freedom of expression. This includes the “freedom
to seek, receive and impart information and ideas of all kinds, regardless of
frontiers, either orally, in writing or in print, in the form of art, or through
any other media of his choice.” This right is also protected under Article 9 of
the African Charter on Human and Peoples’ Rights, to which Ethiopia is a state
party.
Regarding restrictions on access to internet resources, the United Nations Human
Rights Committee has stressed that any restrictions “generally should be
content-specific; generic bans on the operation of certain sites and systems are
not compatible with paragraph 3 of Article 19 of the ICCPR. It is also
inconsistent with paragraph 3 to prohibit a site or an information dissemination
system from publishing material solely on the basis that it may be critical of
the government or the political social system espoused by the government.”
The UN Human Rights Council resolution on the promotion, protection and
enjoyment of human rights on the Internet which was passed on 1 July 2016,
“condemns unequivocally measures to intentionally prevent or disrupt access to
or dissemination of information online in violation of international human
rights law and calls on all States to refrain from and cease such measures.”
The abuse of freedom of expression in the form of propaganda for war, advocacy
of national, racial or religious hatred that constitutes incitement to
discrimination, hostility or violence may be subject to restrictions under the
ICCPR, but these restrictions must meet three requirements laid out in the
covenant. The first requirement is that restrictions must be provided by law,
which is “formulated with sufficient precision to enable an individual to
regulate his or her conduct accordingly”. Additionally, “a law may not confer
unfettered discretion for the restriction of freedom of expression on those
charged with its execution.”
The second requirement is that restrictions must be “necessary” to achieve one
of the enumerated legitimate aims under the ICCPR. The third requirement
provides, among other things, that “restrictive measures must conform to the
principle of proportionality… they must be the least intrusive instrument
amongst those which might achieve their protective function.”
OONI’s findings provide evidence of systematic interference with access to
numerous websites belonging to independent news organizations and political
opposition groups, as well as sites supporting freedom of expression and LGBTI
rights. Such widespread interference and blocking is a violation of Ethiopia’s
obligations under article 19 of the ICCPR.
The restrictions on access to information as per the findings of this report
fail to meet the legality test, which is the first requirement under article
19(3). Ethiopia lacks clear and precise law that governs access to internet and
social media, restrictions/blockade of websites and social media, and the legal
procedures. The inventory of Ethiopian relevant telecommunications, cybercrimes,
security, and intelligence laws reveals the absence of provisions that govern
content control and access to internet in the Country. The laws that established
the Information Network Security Agency and the National Intelligence and
Security Service1 authorize neither of the institutions to restrict access to
internet and social media, censor websites for any reason. The Telecom Fraud
Offences Proclamation does not authorize any of the Government agencies to
control and restrict access to internet, websites, or social media application
in the country.
As such, the blocking of WhatsApp and restrictions of certain websites are
arbitrary, being conducted without any specific national law. Moreover, in the
absence of such law, the country also lacks the administrative and judicial
procedures for challenging such restrictions and blockades.
The internet restrictions also fail the proportionality test, because the
interference is not limited to specific content; rather interference is
happening at a very large scale, with dozens of websites affected over the space
of several months. Similarly, blocking access to WhatsApp, a popular
communications platform in Ethiopia is not a justifiable restriction on freedom
of expression and access to information.
Ethiopia’s practices of restricting access to large numbers of websites, as well
as services such as WhatsApp is therefore a clear violation of the rights to
freedom of expression and access to information.
The ICCPR permits derogation from certain rights during emergencies. However,
such derogations must meet several criteria in order to be lawful. Most
importantly, “the situation must amount to a public emergency which threatens
the life of the nation, and the State party must have officially proclaimed a
state of emergency.” Measures taken subject to a derogation must be “limited to
the extent strictly required by the exigencies of the situation.” The African Charter on Human and Peoples’ Rights does not have a provision that provides for
derogation during emergencies.
The State of Emergency Declaration allows the Command Post to “stop or suspend
any mass media and communications” throughout the country. The geographic
coverage of this measure violates the requirement that derogations under state
of emergency must be limited to exigencies of the situation.
The Ethiopian Government has repeatedly alleged that the violence after the
Irrecha tragedy prompted the declaration of the state of emergency. While the
violence occurred primarily in some districts of Oromia and Amhara, it is
unclear how the exigencies of the situation would strictly require the
imposition of such measures with a geographic scope that covers the whole of the
country.
Conclusion
In the midst of ongoing protests in Ethiopia, access to WhatsApp was found to be blocked, and the covert presence of Deep Packet Inspection (DPI) equipment was
not only unveiled, but it was also found to be filtering access to an
independent Ethiopian media website (ecadforum.com).
Research conducted by OONI between June and October 2016 shows that access to
WhatsApp as well as at least 16 news outlets were blocked prior to the state of
emergency. Also targeted were websites supporting Lesbian, Gay, Bisexual,
Transgender and Intersex (LGBTI) rights, organizations advocating freedom of
expression, sites run by opposition groups and armed movements, as well as
websites that offer censorship circumvention tools, such as Tor and Psiphon.
Interestingly, all of these sites consistently presented HTTP response failures
when queried, while the testing of different versions of the same sites appeared
to bypass the filter in certain cases. This pattern is identical to that of
ecadforum.com, indicating that most (if not all) of the above types of sites
were likely filtered by DPI equipment as well.
The Amnesty International research findings during the same period corroborate
OONI’s findings, indicating that other social media applications were very slow,
not working properly or inaccessible, particularly in regions affected by the
protests.
The evidence suggesting that the government is deploying Deep Packet Inspection
(DPI) technology to filter access to internet traffic is concerning. Though it
has many legitimate functions, DPI enables effective surveillance and filtering
of internet traffic, increasing the States’ ability to restrict access to the
internet, fully or partially, on command.
Many of the acts of censorship identified by OONI took place before a state of
emergency was announced, and violated Ethiopia’s obligation to respect, protect
and fulfill its people’s right to receive and impact information. The acts of
censorship, conducted outside a clear legal framework, over several months and
affecting dozens of websites and social media platforms failed to meet the
criteria set out under the ICCPR for restrictions on freedom of expression.
While the State of Emergency may have subsequently provided a legal framework
under Ethiopian law for some of these measures, the State of Emergency itself is
so broadly drafted that it violates Ethiopia’s international legal obligations
and permits violations of numerous human rights. The power the state of
emergency bestows upon the Command post to monitor and suspend all
communications and media throughout Ethiopia is unnecessarily expansive. The
protests and the violence following the protest have been limited to Oromia,
Amhara, Konso District in Southern Nations Nationalities and Peoples Region
(SNNPR) and Addis Ababa.
Amnesty International and OONI are concerned that unnecessary and
disproportionate censorship of the internet will not only continue during the
state of emergency, but become institutionalized and entrenched.
Recommendations
To Ethiopian authorities
Amnesty International and OONI request the Ethiopian government to respect and
protect and fulfill freedom of expression on the internet. Specifically, they
request the Ethiopian Authorities to:
Refrain from blocking access to the internet
Refrain from unlawful censorship of the internet
Ensure that limitations on the right to seek or impart information on the
internet fully adhere to the requirements of article 19(3) of the ICCPR.
Specifically, that the restrictions comply with the three-tier test of legality,
necessity and proportionality, and that they are subject to judicial review.
To social media companies (e.g. Facebook, Twitter)
Make available publicly verifiable data on network traffic originating from
countries around the world, to ensure transparency when social media
restrictions or heavy network disruption occur.
Part 2: Methodology
The methodology of this study, in an attempt to identify potential censorship
events in Ethiopia, included the following:
OONI’s free software tests were run from a local vantage point (EthioNet) in
Ethiopia. Some tests examined two lists of URLs: the one being relevant to Ethiopia, while the other including URLs that are commonly accessed around the
world. All URLs included in these two lists were tested in terms of blocking.
Other OONI tests were run to examine whether systems that could be responsible
for censorship, surveillance, and traffic manipulation were present in the
tested network. Once network measurement data was collected from these tests,
the data was subsequently processed and analyzed based on a set of heuristics
for detecting internet censorship and traffic manipulation.
The testing period started on 15th June 2016 and concluded on 7th October 2016.
Test lists
An important part of identifying censorship is determining which websites to
examine for blocking.
OONI’s software (called OONI Probe) is designed to examine URLs contained in
specific lists (“test lists”) for censorship. By default, OONI Probe examines the
“global test list”, which includes a wide range of internationally relevant
websites, most of which are in English. These websites fall under 30 categories,
ranging from news media, file sharing and culture, to provocative or
objectionable categories, like pornography, political criticism, and hate
speech.
These categories help ensure that a wide range of different types of websites
are tested, and they enable the examination of the impact of censorship events
(for example, if the majority of the websites found to be blocked in a country
fall under the “human rights” category, that may have a bigger impact than other
types of websites being blocked elsewhere). The main reason why objectionable
categories (such as “pornography” and “hate speech”) are included for testing is
because they are more likely to be blocked due to their nature, enabling the
development of heuristics for detecting censorship elsewhere within a country.
In addition to testing the URLs included in the global test list, OONI Probe is
also designed to examine a test list which is specifically created for the
country that the user is running OONI Probe from, if such a list exists. Unlike
the global test list, country-specific test lists include websites that are
relevant and commonly accessed within specific countries, and such websites are
often in local languages. Similarly to the global test list, country-specific
test lists include websites that fall under the same set of 30 categories, as
explained previously.
All test lists are hosted by the Citizen Lab on GitHub, supporting OONI and
other network measurement projects in the creation and maintenance of lists of
URLs to test for censorship. Some criteria for adding URLs to test lists include
the following:
The URLs cover topics of socio-political interest within the country.
The URLs are likely to be blocked because they include sensitive content (i.e.
they touch upon sensitive issues or express political criticism).
The URLs have been blocked in the past.
Users have faced difficulty connecting to those URLs.
The above criteria indicate that such URLs are more likely to be blocked,
enabling the development of heuristics for detecting censorship within a
country. Furthermore, other criteria for adding URLs are reflected in the 30 categories that URLs can fall under. Such categories, for example, can include
file-sharing, human rights, and news media, under which the websites of file-
sharing projects, human rights NGOs and media organizations can be added.
As part of this study, the URLs included in both the Citizen Lab’s test list for Ethiopia and its global list were tested for blocking.
A core limitation to the study is the bias in terms of the URLs that were
selected for testing. The URL selection criteria, for example, included the
following:
Websites that were more likely to be blocked because their content expressed
political criticism.
Websites of organizations that were known to have previously been blocked and
were thus likely to be blocked again.
Websites reporting on human rights restrictions and violations.
The above criteria reflect bias in terms of which URLs were selected for
testing, as one of the core aims of this study was to examine whether and to
what extent websites reflecting criticism were blocked, limiting open dialogue
and access to information across the country. As a result of this bias, it is
important to acknowledge that the findings of this study are only limited to the
websites that were tested, and do not provide a complete view of other
censorship events that may have taken place before and after the testing period.
OONI network measurements
The Open Observatory of Network Interference (OONI) is a free software project
that aims to increase transparency about internet censorship and traffic
manipulation around the world. Since 2011, OONI has developed multiple free and open source software tests designed to examine the following:
Blocking of websites.
Blocking of instant messaging apps.
Detection of systems responsible for censorship and traffic manipulation.
Reachability of circumvention tools (such as Tor, Psiphon, and Lantern) and
sensitive domains.
As part of this study, the following OONI software tests were run from a local
vantage point in Ethiopia:
The web connectivity test was run with the aim of examining whether a set of
URLs (included in both the “global test list” and the “Ethiopian test list”)
were blocked during the testing period and if so, how. The HTTP invalid request
line and HTTP header field manipulation tests were run with the aim of examining
whether systems (that could potentially be responsible for censorship and/or
surveillance) were present in the tested network. The HTTP host test was run to
not only examine if tested URLs were blocked, but to also examine whether
specific systems were used in the tested network to implement such blocking.
The sections below document how each of these tests are designed for the purpose
of detecting cases of internet censorship and traffic manipulation.
Web Connectivity
This test examines whether websites are reachable and if they are not, it
attempts to determine whether access to them is blocked through DNS tampering,
TCP connection RST/IP blocking or by a transparent HTTP proxy. Specifically,
this test is designed to perform the following:
Resolver identification
DNS lookup
TCP connect
HTTP GET request
By default, this test performs the above (excluding the first step, which is
performed only over the network of the user) both over a control server and over
the network of the user. If the results from both networks match, then there is
no clear sign of network interference; but if the results are different, the
websites that the user is testing are likely censored. Further information is
provided below, explaining how each step performed under the web connectivity
test works.
1. Resolver identification
The domain name system (DNS) is what is responsible for transforming a host name
(e.g. torproject.org) into an IP address (e.g. 38.229.72.16). Internet Service
Providers (ISPs), amongst others, run DNS resolvers which map IP addresses to
hostnames. In some circumstances though, ISPs map the requested host names to
the wrong IP addresses, which is a form of tampering.
As a first step, the web connectivity test attempts to identify which DNS
resolver is being used by the user. It does so by performing a DNS query to
special domains (such as whoami.akamai.com) which will disclose the IP address
of the resolver.
2. DNS lookup
Once the web connectivity test has identified the DNS resolver of the user, it
then attempts to identify which addresses are mapped to the tested host names by
the resolver. It does so by performing a DNS lookup, which asks the resolver to
disclose which IP addresses are mapped to the tested host names, as well as
which other host names are linked to the tested host names under DNS queries.
3. TCP connect
The web connectivity test will then try to connect to the tested websites by
attempting to establish a TCP session on port 80 (or port 443 for URLs that
begin with HTTPS) for the list of IP addresses that were identified in the
previous step (DNS lookup).
4. HTTP GET request
As the web connectivity test connects to tested websites (through the previous
step), it sends requests through the HTTP protocol to the servers which are
hosting those websites. A server normally responds to an HTTP GET request with
the content of the webpage that is requested.
Comparison of results: Identifying censorship
Once the above steps of the web connectivity test are performed both over a
control server and over the network of the user, the collected results are then
compared with the aim of identifying whether and how tested websites are
tampered with. If the compared results do not match, then there is a sign of
network interference.
Below are the conditions under which the following types of blocking are
identified:
DNS blocking: If the DNS responses (such as the IP addresses mapped to host names) do not
match.
TCP/IP blocking: If a TCP session to connect to websites was not established
over the network of the user.
HTTP blocking: If the HTTP request over the user’s network failed, or the HTTP
status codes don’t match, or all of the following apply:
The body length of compared websites (over the control server and the
network of the user) differs by some percentage
The HTTP headers names do not match
The HTML title tags do not match
It’s important to note, however, that DNS resolvers, such as Google or a local
ISP, often provide users with IP addresses that are closest to them
geographically. Often this is not done with the intent of network tampering, but
merely for the purpose of providing users with localized content or faster
access to websites. As a result, some false positives might arise in OONI
measurements. Other false positives might occur when tested websites serve
different content depending on the country that the user is connecting from, or
in the cases when websites return failures even though they are not tampered
with.
HTTP invalid request line
This test tries to detect the presence of network components (“middle box”)
which could be responsible for censorship and/or traffic manipulation.
Instead of sending a normal HTTP request, this test sends an invalid HTTP
request line - containing an invalid HTTP version number, an invalid field count
and a huge request method – to an echo service listening on the standard HTTP
port. An echo service is a very useful debugging and measurement tool, which
simply sends back to the originating source any data it receives. If a middle
box is not present in the network between the user and an echo service, then the
echo service will send the invalid HTTP request line back to the user, exactly
as it received it. In such cases, there is no visible traffic manipulation in
the tested network.
If, however, a middle box is present in the tested network, the invalid HTTP
request line will be intercepted by the middle box and this may trigger an error
and that will subsequently be sent back to OONI’s server. Such errors indicate
that software for traffic manipulation is likely placed in the tested network,
though it’s not always clear what that software is. In some cases though,
censorship and/or surveillance vendors can be identified through the error
messages in the received HTTP response. Based on this technique, OONI has
previously detected the use of BlueCoat, Squid and Privoxy proxy technologies in
networks across multiple countries around the world.
It’s important though to note that a false negative could potentially occur in
the hypothetical instance that ISPs are using highly sophisticated censorship
and/or surveillance software that is specifically designed to not trigger errors
when receiving invalid HTTP request lines like the ones of this test.
Furthermore, the presence of a middle box is not necessarily indicative of
traffic manipulation, as they are often used in networks for caching purposes.
This test also tries to detect the presence of network components (“middle box”)
which could be responsible for censorship and/or traffic manipulation.
HTTP is a protocol which transfers or exchanges data across the internet. It
does so by handling a client’s request to connect to a server, and a server’s
response to a client’s request. Every time a user connects to a server, the user
(client) sends a request through the HTTP protocol to that server. Such requests
include “HTTP headers”, which transmit various types of information, including
the user’s device operating system and the type of browser that is being used.
If Firefox is used on Windows, for example, the “user agent header” in the HTTP
request will tell the server that a Firefox browser is being used on a Windows
operating system.
This test emulates an HTTP request towards a server, but sends HTTP headers that
have variations in capitalization. In other words, this test sends HTTP requests
which include valid, but non-canonical HTTP headers. Such requests are sent to a
backend control server which sends back any data it receives. If OONI receives
the HTTP headers exactly as they were sent, then there is no visible presence of
a “middle box” in the network that could be responsible for censorship,
surveillance and/or traffic manipulation. If, however, such software is present
in the tested network, it will likely normalize the invalid headers that are
sent or add extra headers.
Depending on whether the HTTP headers that are sent and received from a backend
control server are the same or not, OONI is able to evaluate whether software –
which could be responsible for traffic manipulation – is present in the tested
network.
False negatives, however, could potentially occur in the hypothetical instance
that ISPs are using highly sophisticated software that is specifically designed
to not interfere with HTTP headers when it receives them. Furthermore, the
presence of a middle box is not necessarily indicative of traffic manipulation,
as they are often used in networks for caching purposes.
HTTP Host
This test is designed to examine:
Whether the domain names of websites are blocked;
The presence of “middle boxes” (software that could be responsible for
censorship and/or surveillance) in tested networks;
Whether censorship circumvention techniques are capable of bypassing the
censorship implemented by the “middle box”.
OONI’s HTTP Host test implements a series of techniques which help it evade
getting detected from censors and then uses a list of domain names (such as
bbc.co.uk) to connect to an OONI backend control server, which sends the host
headers of those domain names back to OONI. If a “middle box” is detected
between the network path of the probe and the OONI backend control server, its
fingerprint might be included in the JSON data that OONI receives from the
backend control server. Such data also informs OONI if the tested domain names
are blocked or not, as well as how the censor tried to fingerprint the
censorship of those domains. This can sometimes lead to the identification of
the type of infrastructure being used to implement censorship.
Data analysis
Through its data pipeline, OONI processes all network measurements that it
collects, including the following types of data:
Country code
OONI by default collects the code which corresponds to the country from which
the user is running OONI Probe tests from, by automatically searching for it
based on the user’s IP address through the MaxMind GeoIP database. The
collection of country codes is an important part of OONI’s research, as it
enables OONI to map out global network measurements and to identify where
network interferences take place.
Autonomous System Number (ASN)
OONI by default collects the Autonomous System Number (ASN) which corresponds to
the network that a user is running OONI Probe tests from. The collection of the
ASN is useful to OONI’s research because it reveals the specific network
provider (such as Vodafone) of a user. Such information can increase
transparency in regards to which network providers are implementing censorship
or other forms of network interference.
Date and time of measurements
OONI by default collects the time and date of when tests were run. This
information helps OONI evaluate when network interferences occur and to compare
them across time.
IP addresses and other information
OONI does not deliberately collect or store users’ IP addresses. In fact, OONI
takes measures to remove users’ IP addresses from the collected measurements, to
protect its users from potential risks.
However, OONI might unintentionally collect users’ IP addresses and other
potentially personally-identifiable information, if such information is included
in the HTTP headers or other metadata of measurements. This, for example, can
occur if the tested websites include tracking technologies or custom content
based on a user’s network location.
Network measurements
The types of network measurements that OONI collects depend on the types of
tests that are run. Specifications about each OONI test can be viewed through
its git repository, and details about what collected network measurements entail
can be viewed through OONI Explorer or through OONI’s list of measurements.
OONI processes the above types of data with the aim of deriving meaning from the
collected measurements and, specifically, in an attempt to answer the following
types of questions:
Which types of OONI tests were run?
In which countries were those tests run?
In which networks were those tests run?
When were tests run?
What types of network interference occurred?
In which countries did network interference occur?
In which networks did network interference occur?
When did network interference occur?
How did network interference occur?
To answer such questions, OONI’s pipeline is designed to process data which is
automatically sent to OONI’s measurement collector by default. The initial
processing of network measurements enables the following:
Attributing measurements to a specific country.
Attributing measurements to a specific network within a country.
Distinguishing measurements based on the specific tests that were run for their
collection.
Distinguishing between “normal” and “anomalous” measurements (the latter
indicating that a form of network tampering is likely present).
Identifying the type of network interference based on a set of heuristics for
DNS tampering, TCP/IP blocking, and HTTP blocking.
Identifying block pages based on a set of heuristics for HTTP blocking.
Identifying the presence of “middle boxes” within tested networks.
However, false positives and false negatives emerge within the processed data
due to a number of reasons. As explained previously (section on “OONI network
measurements”), DNS resolvers (operated by Google or a local ISP) often provide
users with IP addresses that are closest to them geographically. While this may
appear to be a case of DNS tampering, it is actually done with the intention of
providing users with faster access to websites. Similarly, false positives may
emerge when tested websites serve different content depending on the country
that the user is connecting from, or in the cases when websites return failures
even though they are not tampered with.
Furthermore, measurements indicating HTTP or TCP/IP blocking might actually be
due to temporary HTTP or TCP/IP failures, and may not conclusively be a sign of
network interference. It is therefore important to test the same sets of
websites across time and to cross-correlate data, prior to reaching a conclusion
on whether websites are in fact being blocked. Since block pages differ from
country to country and sometimes even from network to network, it is quite
challenging to accurately identify them. OONI uses a series of heuristics to try
to guess if the page in question differs from the expected control, but these
heuristics can often result in false positives. Due to this, OONI only confirms
an instance of blocking when a known block page has manually been added to the
list of block pages that OONI supports.
However, this means that when a block page is not presented by the censor OONI
cannot confirm with absolute certainty that blocking is occurring. For the
purpose of this study we have extended our methodology to also take into account
unusual failures that could be triggered by the censor. In particular, we have
looked at sites that appear to fail consistently (that is in the same way) and
constantly over the testing period, therefore most likely not due to transient
networking errors.
OONI’s methodology for detecting the presence of “middle boxes” - systems that
could be responsible for censorship, surveillance and traffic manipulation - can
also present false negatives if ISPs are using highly sophisticated software
that is specifically designed to not interfere with HTTP headers when it
receives them, or to not trigger error messages when receiving invalid HTTP
request lines. It remains unclear though if such software is being used.
Moreover, it’s important to note that the presence of a middle box is not
necessarily indicative of censorship or traffic manipulation, as such systems
are often used in networks for caching purposes.
Upon collection of more network measurements, OONI continues to develop its data
analysis heuristics, based on which it attempts to accurately identify
censorship events.
Acknowledgement of limitations
The findings of this study present various limitations, and do not necessarily
reflect a comprehensive view of internet censorship in Ethiopia on a nationwide
level.
The first limitation is associated with the testing period, which started on
15th June 2016 and concluded on 7th October 2016, prior to the declaration of
Ethiopia’s state of emergency. Therefore, censorship events which may have
occurred before and/or after the testing period (such as the reported mobile
internet shutdown in October 2016) were not examined as part of this study.
Furthermore, security challenges for people conducting OONI tests in Ethiopia
limited our ability to perform daily measurements and tests were inevitably run
quite sporadically across the testing period. As such, censorship events that
may have occurred on days that tests were not run might not be included as part
of this study.
Even though measurements were collected from Ethio Telecom, which is Ethiopia’s
main telecommunications service provider, the findings of this study do not
necessarily apply on a nationwide level. Ethio Telecom might have applied
censorship in some locations of Ethiopia, while not in others. Given that OONI
software tests were run from the same location across the testing period, we
cannot know with certainty whether the censorship events found through this
study apply on a nationwide level or not.
Another limitation is associated to the types of URLs that were tested as part
of this study. As mentioned in the methodology section of this report (“Test
lists”), the criteria for selecting URLs that are relevant to Ethiopia presented
bias. While a total of 1,403 different URLs were tested for censorship as part
of this study, not all the URLs on the internet were tested, indicating the
possibility that other websites not included in test lists might have been
blocked.
Finally, the data analysis heuristics as part of this study also present
limitations. This is due to the fact that many false positives almost inevitably
emerge within the collected measurement data, limiting our ability to confirm
censorship events with confidence, especially when block pages are not present.
Warm thanks to Girma Walabuma who took considerable security risks to perform
OONI network measurement tests in Ethiopia for this study, and to the Open Technology Fund for funding OONI’s work.