IP Header Compression Context Reordering for Packet Flow Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In networks implementing both IP header compression and traffic management, packets with expired context identifiers can cause errors and data loss due to incorrect forwarding or discarding when congestion subsides and context identifiers are reassigned.
Innovation Solution
A network node method that assigns a compression context identifier to packets, queues them based on quality of service (QoS), and discards packets if the QoS no longer matches the stored context identifier, ensuring that expired packets do not interfere with new compression contexts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If packets are queued in low priority queue during congestion, then traffic management prioritization is improved, but context identifier expiration and packet forwarding errors occur
Solution Approach 1:
The system performs preliminary validation by checking whether the context identifier stored in the packet header still matches the current context identifier in the context table before forwarding the packet. This preliminary check prevents expired packets from causing forwarding errors while allowing legitimate packets to proceed normally.
Solution Approach 2:
The system implements a feedback mechanism where the context identifier validation result determines the packet's fate: if the context identifier matches, the packet is forwarded; if it doesn't match (indicating expiration), the packet is discarded. This feedback loop ensures that traffic management prioritization does not compromise forwarding accuracy.
2Productivity
If context identifier is reassigned to new flow, then resource utilization is improved, but packet generation mismatch and data loss occur
Solution Approach 1:
Before reassigning a context identifier to a new flow, the system validates incoming packets to ensure they belong to the correct flow by checking context identifier matching. This preliminary validation ensures that reassigned context identifiers do not cause data loss from generation mismatches.
Solution Approach 2:
The system changes the state parameter of the context identifier from 'active' to 'expired' or 'reassigned' to track its lifecycle. This parameter change mechanism allows the system to efficiently manage context identifier reuse while preventing data loss from mismatched packets.
3Ease of operation
If full header packets are sent during congestion resolution, then context reset and flow reinitialization occur, but new flow packets are incorrectly discarded
Solution Approach 1:
The system performs preliminary context identifier validation on all incoming packets, including full header packets, before processing them. This preliminary check ensures that full header packets from expired flows are identified and handled appropriately without incorrectly discarding packets from new flows that may have the same context identifier.
Data Source
AI summary
Various exemplary embodiments relate to a method and related network node including one or more of the following: receiving, at the network node, a packet belonging to a flow, the packet including a marking used to identify a quality of service (QoS) required for the packet; assigning a compression context identifier to the packet; queuing the packet in a queue selected from a plurality of queues based on the marking in the packet; identifying a period of congestion and, in response, blocking the packet; when the period of congestion has ended and the packet is dequeued, determining whether the QoS associated with the packet is the same as a QoS stored in a context identifier storage; and when the QoS associated with the packet is not the same as the QoS stored in the context identifier storage, determining that the flow has expired and discarding the packet.