During Egypt's 5.5-day Internet blackout, active CAIDA Ark measurements found that only 1% of probes to Egyptian IPv4 prefixes received responses, compared to 16–17% on normal days. The minority of addresses that retained bidirectional connectivity all mapped to BGP prefixes that had not been withdrawn—including prefixes serving the Egyptian stock exchange and two national banks, whose 83 prefixes were kept live until January 31 at 20:46:48 GMT before being simultaneously withdrawn.

Both Egypt and Libya demonstrate that concentration of Internet infrastructure under state ownership—in Egypt, all submarine fiber backhaul terminated at a single facility, the Ramses Exchange, controlled by the state telecommunications provider—makes country-wide BGP-based shutdowns technically straightforward. The authors conclude that the small number of state-controlled parties involved in international connectivity was the critical enabling factor, not any novel technical capability.

§5.1.1 policy

Unsolicited background radiation traffic to the UCSD network telescope—particularly Conficker worm scanning (TCP SYN, port 445, 48-byte packets)—dropped nearly simultaneously with Egyptian BGP route withdrawals on January 27, corroborating control-plane analysis with data-plane evidence. Crucially, some worm-infected hosts continued to generate outbound scanning traffic even after their prefixes were BGP-withdrawn, because packet filtering was absent; this asymmetry between inbound unreachability and outbound connectivity can distinguish pure BGP-based blocking from combined BGP-plus-filtering approaches.

§4.3, §5.1 evaluation

Egypt's Internet shutdown on January 27, 2011 was accomplished via BGP route withdrawals: approximately 2,500 IPv4 prefixes (out of 2,928 visible) disappeared within a 20-minute window beginning at 22:12:26 GMT, leaving only 176 prefixes visible by 23:30:00 GMT. The shutdown lasted more than five days, with BGP connectivity beginning to return at 09:29:31 GMT on February 2, and more than 2,500 Egyptian prefixes back in global BGP tables by 09:56:11 GMT.

§5.1.1, §5.1.2 evaluation

Libya implemented escalating Internet disruptions before executing a sustained blackout: a 6.8-hour curfew on February 18 and an 8.3-hour curfew on February 19, followed by a 3.7-day near-total blackout beginning March 3. The authors detected what they believe were Libya's attempts to test firewall-based packet filtering before transitioning to more aggressive BGP-based disconnection, demonstrating a two-phase escalation pattern.

§1, §5.2 evaluation

On March 28, 2022, Russian ISP RTComm (AS8342) hijacked Twitter's IPv4 prefix 104.244.42.0/24 for approximately 45 minutes (12:05–12:50 UTC) and announced it to the global Internet as a blocking measure. The hijack was blunted because Twitter had preemptively registered RPKI route origin authorizations (ROAs) for its prefixes, causing RPKI-validating ASes worldwide to reject the hijacked route.

2023-ramesh-network §4.3 bgp-hijackasn-blackholing

Iran and Libya each have a single point of control (1 AS), making complete national internet shutdown achievable with a single administrative action. Egypt's 2011 shutdown left one AS (Noor Group, 4.9% of connected IPs) operational for four days, apparently due to its role serving the Egyptian stock exchange and other core financial institutions.

2011-roberts-mapping §VI, Figure 7 asn-blackholingbgp-hijackthrottling

Article 19 documents that Iran's National Information Network (NIN / SHOMA) was designed with explicit reference to China's Great Firewall as a model, with institutional mirroring: Iran's Supreme Council of Cyberspace parallels China's Cyberspace Administration of China, and both governments share a "cyber sovereignty" doctrine used to justify domestic content controls and cross-border technology transfer. The report frames Iran's filtering infrastructure as deliberately architected to replicate GFW capabilities, not as an independently developed system.

2026-article19-tightening-the-net §2, §3 dpisni-blockingdns-poisoningip-blockingbgp-hijackthrottling

Brussee measures a systematic pattern of Chinese government websites actively blocking access from outside China (the "reverse Great Firewall"), publishing a CSV dataset of affected domains (available at zenodo.org/records/18172145). The paper frames this outbound geo-blocking as a cybersecurity-motivated practice — Chinese authorities classify foreign access to domestic government infrastructure as an attack surface — distinct from the inbound information control goal of the GFW.

2026-brussee-reverse-great-firewall §3, §5 ip-blockingasn-blackholing

Brussee develops a conceptual framework distinguishing two logics of government geo-blocking: (1) information control (blocking inbound foreign content from domestic users) and (2) data sovereignty / attack-surface reduction (blocking outbound access by foreign actors to domestic systems). Chinese government site blocking of external IPs is motivated primarily by the second logic, creating an asymmetric internet topology where CN citizens cannot reach the outside world, and outside actors cannot probe CN government infrastructure.

2026-brussee-reverse-great-firewall §2, §4 ip-blockingasn-blackholing

NetShuffle targets edge networks — small autonomous systems and entities that obtain IP address blocks from upstream providers — as a new class of support base for circumvention infrastructure. This class has received scant attention from prior work, which has focused on cloud providers and volunteer desktop machines. Edge networks represent a large pool of diverse IP space that is harder to block via ASN blackholing compared to a small number of major cloud providers.

2024-kon-netshuffle §1, §2 ip-blockingasn-blackholing