Challenges

To define which errors can be defined for the different services a list of potential challenges to the network is collected. More and more challenges will be added during the ongoing work but the list will never be complete (see axiom 2).

Large-Scale Disasters

Large scale disasters damage or destroy a significant part of the network infrastructure in an area beyond local scope, for example a large city or region. Fault tolerance mechanisms are insufficient due to the large number of correlated failures that result.

Natural Disasters

Natural disasters are those beyond the control of humans, and whose consequences are severe even when reasonable precautions are taken.

Examples of such disasters include hurricanes, tsunami, earthquakes, and ice storms.

Man-Made Disasters

Man-made disasters include those created accidentally or intentionally by humans, or are a result of human incompetence.

Examples of such disasters include regional power failures for a considerable length of time.

Unusual but legitimate traffic

• flash crowds
• sequence of data packets where each packet complies to the service specification but the sequence does not

Challenges in wireless networks

• dis-connect due to node movement
• route changes due to node movement
• noisy channels
• high-mobility of nodes and subnetworks
• weak, asymmetric, and episodic connectivity of wireless channels
• unpredictably long delay paths either due to length (e.g. satellite) or as a result of episodic connectivity
• resource limitation due to battery powered

Attacks

Software based attacks

Attacks against the network hardware, software, or protocol infrastructure from recreational crackers, industrial espionage, terrorism, or warfare

“A "denial-of-service" attack is characterised by an explicit attempt by attackers to prevent legitimate users of a service from using that service. Examples include:

• attempts to "flood" a network, thereby preventing legitimate network traffic
• attempts to disrupt connections between two machines, thereby preventing access to a service
• attempts to prevent a particular individual from accessing a service
• attempts to disrupt service to a specific system or person”

CERT

• DDoS attacks
• Data injection attacks, e.g. TCP injection
• Connection reset attacks
• Truncation attacks
• Downgrade security scheme attack
• System break-in
• Data redirection attack
• Address and identity spoofing
• Man-in-the-middle attack
• Disclosure of secret data
• Side-channel attacks
• Timing attacks

Real-world attacks

• Large-scale natural disasters e.g. hurricanes, earthquakes, ice storms, tsunami, floods
• Damage due to accidents or construction works
• Terrorist attacks

Mis-configuration

Failures due to mis-configuration or operational errors

• Firewall blocks legal traffic
• Routing protocol announces wrong prefix-route combination
• load balancer does not use all ressources
• name resolution maps name to wrong path
• routing loops

Natural faults

• Aging of network components