Black Hole Management in Computer Networks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current network protocols face delays and inefficiencies due to 'black holes' caused by network equipment discarding large packets without sending ICMP error messages, leading to undetected transmission failures and increased communication overhead.
Innovation Solution
The solution involves inferring black hole status without proactive probing, suppressing unnecessary probing when no black hole is indicated, and increasing packet size on connections previously identified with black holes when their status changes, thereby reducing transmission delays and overhead.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If network equipment sends ICMP packets to alert source computer of packet size issues, then transmission problems can be detected faster, but ICMP packets may be blocked by administrators or used in denial of service attacks
Solution Approach 1:
The patent introduces an intermediary probing mechanism that indirectly detects black hole conditions by sending test packets through the network path and analyzing responses, rather than relying directly on ICMP error messages that may be blocked. This intermediary approach allows detection of transmission problems without using the problematic ICMP packets.
Solution Approach 2:
The system implements feedback by monitoring whether probing packets receive proper responses or acknowledgments from destination systems. When probing packets fail to elicit expected responses, the system infers the presence of a black hole condition and adjusts transmission behavior accordingly, creating a closed-loop detection and correction mechanism.
2Reliability
If black hole probing is performed to detect transmission issues, then black hole conditions can be identified, but probing creates additional communication overhead and delays
Solution Approach 1:
The patent applies partial action by performing probing only selectively under specific conditions (when transmission failures occur) rather than continuously or proactively for all connections. This reduces the overall probing overhead while maintaining adequate detection capability when problems arise.
Solution Approach 2:
The system performs preliminary probing actions to detect black hole conditions before they cause significant transmission delays. By detecting issues early through probing and preemptively adjusting packet sizes or routing, the system prevents the accumulation of retransmission delays that would occur without early detection.
3Productivity
If packet size is increased on connections previously identified with black holes, then transmission efficiency improves, but the connection may still have unresolved black hole issues
Solution Approach 1:
The patent implements dynamic adaptation by continuously monitoring connection status and adjusting packet sizes based on current conditions rather than using fixed sizes. The system can increase packet sizes when conditions improve (black hole resolved) and decrease them when problems recur, creating a flexible, adaptive transmission strategy that responds to changing network conditions.
Solution Approach 2:
The system changes transmission parameters (packet size) based on detected black hole conditions and their resolution. When a black hole is detected, packet sizes are reduced to bypass the problem; when probing indicates the black hole is resolved, packet sizes are increased to improve efficiency, thereby dynamically adjusting parameters to optimize both reliability and productivity.
Data Source
AI summary
A computer system with black hole management. The black hole management system shares black hole status information among connections that employ the same path. The black hole status information may indicate either that a black hole exists on the path or that communications have been performed successfully on the path, indicating that no black hole exists. By sharing this information, delays in transmission caused by black hole probing may be reduced. Additionally, status information for a connection is reset when information indicates that the connection has been altered. By resetting the status information, delays in transmission associated with sending reduced sized packets over connections for which black holes were previously detected but may have been eliminated by changes in the connection, are avoided.