4.4 Routing Security

Key Concepts

• Routing Protocol Authentication
• Prefix Filtering
• Route Manipulation Prevention
• BGP Security

Routing Protocol Authentication

Routing Protocol Authentication ensures that only trusted routers can participate in routing updates. This prevents unauthorized devices from injecting false routing information into the network. Common methods include MD5 authentication for OSPF and EIGRP, and keychains for BGP.

Example: Think of routing protocol authentication as a secure handshake between routers. Only routers with the correct secret code (authentication key) can exchange routing information, ensuring that outsiders cannot interfere.

Prefix Filtering

Prefix Filtering involves configuring routers to accept or reject specific IP address prefixes in routing updates. This helps prevent the propagation of unwanted or malicious routes. Prefix filters can be applied at the ingress and egress points of a network.

Example: Consider prefix filtering as a customs check at a border. Only routes (packages) with approved labels (prefixes) are allowed to enter or leave the network, ensuring that unwanted or harmful routes are blocked.

Route Manipulation Prevention

Route Manipulation Prevention techniques protect against attacks that attempt to alter routing tables to redirect traffic to malicious destinations. This includes measures like route filtering, route poisoning, and using secure routing protocols.

Example: Imagine route manipulation prevention as a security system that detects and prevents any tampering with the network's traffic signs (routing tables). If someone tries to change the signs to redirect traffic to a dangerous area, the system immediately corrects it.

BGP Security

BGP (Border Gateway Protocol) Security focuses on securing the exchange of routing information between different autonomous systems (ASes). Key measures include using BGP communities, route filtering, and BGPsec (BGP Security Protocol) to ensure the integrity and authenticity of BGP updates.

Example: Think of BGP security as international diplomacy protocols that ensure secure and trustworthy communication between different countries (ASes). By using agreed-upon rules and verification methods, BGP security prevents misinformation and ensures reliable routing across the global internet.