IP transit isn't just a technical term, it's the backbone that keeps the global network running. The easiest way to understand, IP transit is to think of it as the high-speed motorways of the Internet, where data crosses countries, continents connecting companies, governments and individuals in the blink of an eye.
Why is IP traffic so important?The answer is simple. In our globally interconnected world, the efficient and reliable transfer of data transfer is paramount. IP Transit ensures that data packets follow the most efficient routes through the complex web of global networks.
1. The structure of the Internet
It is important to know the structure of the Internet, in order to understand IP traffic.
The Internet is a essentially a network of networks, made up of autonomous systems (ASes) managed by ISPs and connected by Internet Exchange Points (IXPs). It uses a variety of connection methods, including fibre optics, DSL, microwave and satellite, to provide global connectivity. This makes it possible to exchange data and access the Internet seamlessly, regardless of device or region.
The infrastructure of the Internet:
- • Autonomous Systems (ASes) form the backbone of the Internet;
- • Internet Exchange Points (IXPs) is where ASes exchange traffic;
- • Internet service providers (ISPs) provide different forms of access to end users;
- Connections across the Internet uses various technologies including subsea cables, Wi-Fi, mobile and satellite networks.
The IP transit service is created when an ISP allows other networks (such as other ISPs, companies or different ASes) to transmit data over its network. This service is essential for small ISPs or for networks that don't have the infrastructure to access all parts of the Internet on their own.
2. Network agreements and technologies
The functionality and vast reach of the Internet is maintained through a complex web of relationships and connections between different networks comprising Internet service providers, companies, clouds, content distribution networks, etc. To understand these relationships, let's take a closer look at how they are established. There are two ways of doing this: peering and transit.
a. Peering service:
Peering is a network agreement between ISPs for the direct exchange of traffic. This exchange is generally free of charge. Peering reduces latency and dependence on third- party networks. There are two main types of peering: public and private. Public peering takes place at Internet exchange points (IXPs), where many networks meet. Private peering is a direct connection between two networks.
b. Transit service:
Transit is a service through which one network gives another network access to the entire Internet. Unlike peering, transit is a customer-provider relationship. Small networks pay providers for transit in order to access the rest of the Internet. Transit is vital for small ISPs.
c. Dedicated Internet Access (DIA):
DIA is a high-speed internet connection that is dedicated to your business and not shared with other companies. Dedicated internet access is delivered via an ethernet or private line connection, with the aim of providing highly-secure and reliable internet connectivity for companies to manage their operations.
d. How do they work together?
The diagram below shows how the different parts of the Internet are connected using transit and peering. It illustrates how requests for Internet access (from individuals or companies) are routed through different networks
- Transit service provider: The cloud in the centre represents a large network services company that moves Internet traffic over long distances. It is like a highway or motorway operator that allows many different drivers (data) to use its roads.
- b. Internet service providers: The clouds labelled "ISP 1", "ISP 2" and "ISP 3" represent the companies that give everyone access to the Internet. They are like the local roads that connect homes and businesses to the wider highways.
- Connections: Transit connections show how ISPs connect to a larger transit provider to send and receive data. Peering connections show how ISPs interconnect with each other. In addition, dedicated Internet connections are the final path taken by data to reach its destination.
- Hierarchy: Transit providers can also be ISPs. Tier 1 ISPs have large networks for global access and compete exclusively with each other. Tier 2 and Tier 3 ISPs have smaller scales. They can buy or rent Internet access from larger Tier 1 ISPs and connect to the wider Internet (IP transit).
3. Transit routing (AS and BGP)
Routing is essential for navigating or directing data through the complex network of Internet networks. In peering, networks exchange routing information to send and receive data directly. In transit, a provider offers wider access by routing customer data across the entire Internet. These routing processes guide data packets along optimal paths to their destinations, shaping the connectivity and functionality of the Internet.
When it comes to routing, there are two important concepts to consider and which come up frequently: AS and BGP:
- • AS (Autonomous System): An AS is a collection of connected Internet routes under the control of one or more network operators (or ISPs). Each AS is assigned a unique number, called an ASN, which allows it to be identified on the global Internet. This system allows large networks to effectively manage their routes and policies, thus ensuring the smooth flow of traffic on the Internet.
- • BGP (Border Gateway Protocol): BGP is the cartographer of the Internet, deciding on the best routes for data to flow efficiently and securely. The BGP protocol can be eBGP (outer BGP) or iBGP (inner BGP). eBGP is used for routing between different ASes on the Internet, while iBGP is used for routing within a single AS.
- How do ASs communicate using BGP?
The following diagram illustrates how different Autonomous Systems (ASes) communicate using the BGP protocol. It shows how separate Internet networks use BGP to send data between different networks and between themselves - in the most efficient way possible.
- • Autonomous Systems (AS): Each circle represents a network or AS, labelled with a number such as "AS 101".
- • BGP routers: Within each AS, there is a router. The routers use the BGP protocol to communicate, which ensures that the data follows the best route.
- • eBGP and iBGP: eBGP connects routers located in different ASes. iBGP, on the other hand, connects routers within the same AS.
b. IP transit via BGP routing + security (with RPKI)
Now that you know the basics of AS and BGP, let's introduce the concept of transit. We'll also add security to the mix, with RPKI (Resource Public Key Infrastructure) which adds an extra layer of security to BGP routing. This security protocol ensures that data follows the correct paths, avoiding routing errors and potential malicious attacks.
The following diagram illustrates the interaction between corporate networks and Internet service providers in order to manage data flows efficiently and securely, using BGP for routing and RPKI for route security.
- • Enterprise networks (AS102 and AS103): Here, the two circles AS102 and AS103 representing the two separate enterprise networks, each with its own AS. Each AS has an eBGP router that determines the best path to send its Internet traffic. Both companies need a transit service to the Internet.
- • ISP (AS101): This is the network of an Internet Service Provider (ISP) that connects businesses to the Internet at large. The ISP uses an eBGP router to manage incoming and outgoing Internet traffic. This ISP is the IP transit provider.
- • RPKI validation: All networks have RPKI validation to ensure that data paths are secure and authorised. It's like a security checkpoint that prevents traffic from travelling in the wrong direction. The "RIR RPKI Repository Cache" is the centralised authority that issues security passes for these checkpoints.
- • Other ISPs and companies: The cloud represents many networks that are part of the Internet, all connected to the Internet's central cloud.
Africa's Internet Environment
With approximately 480 million users, Internet penetration in Africa is around 28 percent, significantly lower than the global average of 60 percent. Just over one in ten households in Africa is currently connected to the net.
Despite this delay, the number of connected users on the continent grew seven times the world average between 2000 and 2012, according to Internet World Statistics. "Africa has achieved penetration that has broken the 15 per cent barrier and that's important," says Nii Quaynor, known as the "father of the internet" in Africa.
Most sub-Saharan countries produce very few professionals and there are no strategies for investing in technology. Countries focus on the use and consumption of technology, but not on the design, production and expansion of the internet, which is what builds the economy.
However, Internet development in Africa has come a long way since the mid-1990s and especially in the 2000s, thanks to changes in policies and regulations. These are changes that have been achieved thanks to the efforts of leaders like Nii Quaynor.
"The main challenge was preparing the environment. The policies, the businesses, the economy, everything was new," says Quaynor. The slowness of African governments to pass laws to promote the development and use of ICT infrastructure has been one of the biggest difficulties.
The second wave of the digital revolution began with the connection to the world via submarine cables.
Until 2002, the only way to connect sub-Saharan Africa to the world was via satellite connections, which were very expensive and had little capacity. The new submarine connections have meant a remarkable increase in data transmission capacity and have drastically reduced transmission time and costs.
Submarine cables have allowed countries to share information both within the continent and with the rest of the world more directly, creating more space for innovation, research and education.
Angola Cables has its own submarine cable network (WACS, SACS and MONET), covering more than 33,000 kilometres, and extends its services to more than 50,000 kilometres through partner cables, connecting the Americas, Africa, Europe and Asia.
More than 70 per cent of Internet traffic in Africa currently passes through a point on Angola Cables' network, which in turn, is responsible for 1 per cent of the world's Internet traffic.
Angola Cables was recently ranked as the 21st largest global Internet interconnection operator by the Centre for Applied Internet Data Analysis (CAIDA).
With a robust infrastructure that already processes more than 18,488 Tbps, Angola Cables offers high-performance connectivity solutions, enabling efficient delivery of global content at a local level, offering low latency, high resilience and security.
Although Africa is surrounded by submarine cables, countries in the interior have greater difficulties connecting to them.
It's up to governments and regional economic communities to implement policies that allow inland countries to benefit from international connectivity.
Africa's connection with the world is advanced and the connection between African countries is underway. However, there is one last aspect to be tackled, perhaps the most difficult: the internal connection of each country.
We can conclude that Internet is generating social and economic value across the African continent, with the aim of supporting entrepreneurship and promoting innovation. Some countries have made significant progress and other countries can learn from this experience.
Reducing digital divides requires action in four areas: greater access to Internet infrastructure, better purchasing capacity, more relevant local digital content and services, and broader digital skills.
Reduzir as divisórias digitais requer ação em quatro áreas: maior acesso à infraestrutura da Internet, melhor capacidade de aquisição, serviços e conteúdo digital local mais relevantes e habilidades digitais mais amplas.
By: Marinela Liomba, Product Manager, Angola Cables
