One of the topics addressed at the LAC Peering Forum 2022 during the LACNIC 37 event in Cali, Colombia, was the status of the use of Content Delivery Network (CDN) services in Brazil. It is estimated that 80% of traffic of a residential ISP (Internet Service Provider) corresponds to streaming services and that 84% of Internet users in Brazil are subscribed to at least two streaming services. Brazil ranks second worldwide on the list of countries with the highest levels of streaming service consumption.
CDN networks are comprised of groups of servers spread across the Internet to help distribute the content of streaming companies easily, quickly, and securely. These servers can be installed in data centers, ISPs, and Autonomous System networks connected to Internet Exchange Points (IXPs).
In addition to video, CDN networks can also deliver other applications such as web objects (texts, graphics, scripts), e-commerce portals and social media.
When a user accesses a streaming service through their smart TV, smartphone, or computer, they are directed to a cloud server that is responsible for their authentication. Once authenticated, the user will be directed to a server closer to the location from where they are connecting to the Internet and this server will be responsible for delivering the desired content.
Because they exchange high volumes of traffic with CDN networks, ISPs enter into agreements that allow CDN companies to provide a server —known as a cache— that is then installed in the ISP’s structure. Thus, the CDN provides the hardware and the ISP provides the physical infrastructure, a collaboration from which everyone benefits.
The participation of content delivery companies in IXPs allows traffic exchange to grow and motivates other ISPs to connect to Internet Exchange Points. An example of this is IX.br São Paulo, which is currently the world’s largest IXP in terms of its number of participants (interconnected networks) and peak daily traffic.
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A few years ago, when Google connected to IX.br São Paulo in 2008, it had 43 participants and traffic peaks of 4.65 Gbps. Now, 14 years later, IX.br São Paulo allows more than 2,300 Autonomous Systems to exchange traffic, with traffic peaks of over 16 Tbps. Currently, in addition to Google, other CDN companies are also connected, among them Netflix, Globo.com, Amazon, Facebook, Microsoft, Edgecast, Cloudflare, Akamai, Fastly, Azion, Twitch, StackPath, ByteDance, and Apple.
Between March 2020 and March 2022, IX.br São Paulo saw the number of participants grow by 28%, while peak traffic increased by 78% during the same period. Part of this growth was the result of the changes in Internet utilization that occurred during the COVID-19 pandemic, which included an increase in the use of streaming services. It is estimated that 67% of the traffic exchanged at IX.br São Paulo occurs between CDN companies and ISPs.
Case study: Delivery of streaming services by CDN companies
A few years ago, when Google connected to IX.br São Paulo in 2008, it had 43 participants and traffic peaks of 4.65 Gbps. Now, 14 years later, IX.br São Paulo allows more than 2,300 Autonomous Systems to exchange traffic, with traffic peaks of over 16 Tbps. Currently, in addition to Google, other CDN companies are also connected, among them Netflix, Globo.com, Amazon, Facebook, Microsoft, Edgecast, Cloudflare, Akamai, Fastly, Azion, Twitch, StackPath, ByteDance, and Apple.
Between March 2020 and March 2022, IX.br São Paulo saw the number of participants grow by 28%, while peak traffic increased by 78% during the same period. Part of this growth was the result of the changes in Internet utilization that occurred during the COVID-19 pandemic, which included an increase in the use of streaming services. It is estimated that 67% of the traffic exchanged at IX.br São Paulo occurs between CDN companies and ISPs.
Case study: Delivery of streaming services by CDN companies
The IX.br team conducted a study to test five streaming services and analyze content delivery. The intention was to identify which servers would deliver the videos, the proximity between users and content, and determine whether the IX.br structure would be used in this delivery. The tests were performed using IPvFoo, an extension that can be installed in Firefox and Google Chrome browsers. Some geolocation sites were also used to help with the analysis.
The tests involved the use of two different Internet connections, one via Claro, a provider in the city of São Paulo, the other via CILNET, a provider in Cerquilho, a city located 142 km from São Paulo.
The following streaming services were tested:
YouTube: Video of a Brazilian singer
YouTube: Video of an Argentinian singer
YouTube: Video of goals scored by the Brazil national football team
YouTube: Video of goals scored by the Argentina national football team
Netflix: Movie 1
Netflix: Movie 2
Disney Plus: Movie 1
Disney Plus: Movie 2
Disney Plus: Documentary
Amazon Prime Video: Movie 1
Amazon Prime Video: Movie 2
GloboPlay: Novela 1
GloboPlay: Novela 2
The tests were conducted on different days. Likewise, the content selected for the tests was varied and included recently released and older films with the intention of verifying whether the number of requests would somehow influence the delivery of the content.
One of the points noted during the YouTube tests was that delivery could vary depending on which video was streamed. For example, videos in high demand by Brazilians were delivered by servers in Brazil, while videos with low demand in Brazil (for example, the goals scored by the Argentina national football team) were delivered by a server located in Buenos Aires, Argentina.
Another point that was observed was the high number of CDN companies delivering content over IPv6, especially in the tests conducted via the Internet provider in São Paulo.
Conclusions: Geolocation sites do not always point to the exact location of the servers, but they help us get an idea of where content is located. Traceroute and hostname tests also reveal information about the servers’ location.
In the case of tests where CDN companies and the ISP are connected to IX.br São Paulo and have an open peering policy, the traffic exchange possibly occurs through this structure. IX.br São Paulo is also used for server updates through IP transit connections between companies.
Video delivery depends on a number of factors, such as the number of searches for the specific video, the number of times the video has been viewed, the routing policy, and existing agreements between different companies.
In the case of tests where the content was being delivered by a server located outside Brazil, video quality was not compromised. Thus, in addition to the proximity of the content, another very important factor is the quality of the Internet connection of the user of the streaming service.
