Networking Protocols are Foundational for Embedded Systems
A recent episode of the *Embedded* podcast argued that a deep understanding of networking protocols is essential for modern embedded systems engineers. Guest Kenneth Finnegan discussed the importance of deciphering the "alphabet soup" of the internet, including protocols like BGP and OSPF. The discussion highlighted how small configuration choices in a connected device can have cascading effects on network reliability and security.
- Border Gateway Protocol (BGP) is the core routing protocol of the internet, responsible for exchanging routing information between different large networks, known as autonomous systems (AS). It functions as the postal service of the internet, choosing the best paths for data to travel across these massive networks. - Open Shortest Path First (OSPF), by contrast, is an interior gateway protocol used to route traffic *within* a single autonomous system, like a corporate or university network. It uses the "Shortest Path First" algorithm to determine the most efficient route based on factors like link speed, prioritizing speed over the policy-based decisions of BGP. - BGP was designed without strong security mechanisms and operates on a system of trust, making it vulnerable to "BGP hijacking". This occurs when an autonomous system incorrectly announces that it owns IP addresses that actually belong to another entity, redirecting traffic. - These hijacks can be accidental but have massive consequences. In 2008, Pakistan Telecom attempted to block YouTube domestically but inadvertently announced its routes to the global internet, redirecting much of the world's YouTube traffic and causing a multi-hour worldwide outage. - Malicious BGP hijacking is also a significant threat. In a 2018 incident, attackers redirected traffic intended for Amazon's DNS service to steal approximately $152,000 in cryptocurrency by sending users to a fake website. - For resource-constrained embedded systems, like those in the Internet of Things (IoT), incorrect OSPF configurations can be particularly problematic, leading to excessive processing overhead and increased power consumption. - Most large networks use both protocols in conjunction. OSPF is typically used to manage traffic efficiently within the internal network, while BGP is used to connect that network to the broader internet and other autonomous systems.
