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PSC TCP Kernel Monitor

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... As shown in Fig. 1, MAGNeT differs from tcpdump-like measurement tools in that it can monitor traffic at the application level, (i.e., before it traverses the protocol stack), and throughout the entire protocol stack, as well as traffic entering and leaving the network. The only other measurement tool that makes similar measurements is the TCP kernel monitor from Pittsburgh Supercomputing Center [17]. MAGNeT differs from the TCP kernel monitor in at least three ways. ...
... 1, MAGNeT differs from tcpdump-like measurement tools in that it can monitor traffic at the application level, (i.e., before it traverses the protocol stack), and throughout the entire protocol stack, as well as traffic entering and leaving the network. The only other measurement tool that makes similar measurements is the TCP kernel monitor from Pittsburgh Supercomputing Center [17]. MAGNeT differs from the TCP kernel monitor in at least three ways. ...
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Over the last decade, network practitioners have focused on monitoring, measuring, and characterizing traffic in the network to gain insight into building critical network components (from the protocol stack to routers and switches to network interface cards). Previous research shows that additional insight can be obtained by monitoring traffic at the application level (i.e., before application-sent traffic is modulated by the protocol stack) rather than in the network (i.e., after it is modulated by the protocol stack). Consequently, this paper describes a monitor for application-generated network traffic (MAGNeT) that captures traffic generated by the application rather than traffic in the network. MAGNeT consists of application programs as well as modifications to the standard Linux kernel. Together, these tools provide the capability of monitoring an application's network behavior and protocol state information in production systems. The use of MAGNeT will enable the research community to construct a library of real traces of application-generated traffic from which researchers can more realistically test network protocol designs and theory. MAGNeT can also be used to verify the correct operation of protocol enhancements and to troubleshoot and tune protocol implementations
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Transmission Control Protocol
[RFC793] "Transmission Control Protocol." IETF RFC 793, September 1981. Available from: http://www.rfc-editor.org/rfc/rfc793.txt.