Wireshark.STE——通过Wireshark排查应用问题.ppt

Support Technical Exchange Web site http://www-306.ibm.com/software/sysmgmt/products/support/supp_tech_exch.html,08/25/1975,Utilization of Software Tool “WireShark“ to Trouble Shoot TEC and other Application issues,2,08/25/2009,Why would you ever need to trace the network?,Although this never happens, we can get into a situation where a client application or vendor is trying to “blame” us for a certain behavior The network tracing can give us additional insight to help with problem determination and resolution Avoid “Finger Pointing” and get to the root of the problem!,3,Calvin Moody and Roy Spencer,08/25/2009,Presentation Objectives,Overview of TCP stack and a typical TCP/IP packet exchange UDP vs TCP/IP, the OSI model, IPs, Sockets and Interfaces Methods/tools/execution for network tracing Making sense of the gathered trace.,4,Calvin Moody and Roy Spencer,08/25/2009,What is TCP/IP,TCP/IP = Transmission Control Protocol – Internet Protocol. Originally invented by the DOD as a method for computers from different manufactures to communicate with one another, the protocol has become the standard for the majority of network based communication. The protocol works on the concept of “guaranteed deliverability” meaning that each packet transmitted contains a checksum control which requires acknowledgement from the remote receiving host. Should the transmitting system not receive the acknowledgement the last packet transmitted will be resent thus assuring delivery of the packet.,5,Calvin Moody and Roy Spencer,08/25/2009,A Basic TCP/IP example,TCP/IP is a method for computer systems from different manufactures to talk to each other Uses a protocol standard to define the conversation The ability to analyze these conversations will help us become more effective in our troubleshooting,6,Calvin Moody and Roy Spencer,08/25/2009,An Overview of the typical TCP/UDP exchange,I have found this diagram to be the best representation of the overall picture TCP is “guaranteed packet deli