{"guid":"6afe9919-dd80-507d-8ab6-16df8e487920","title":"my hobby dabbles at examining network traces","subtitle":null,"slug":"osmodevcon2024-195-my-hobby-dabbles-at-examining-network-traces","link":"https://pretalx.sysmocom.de/osmodevcon2024/talk/QRBB9Y/","description":"Often I get a 3GPP related network trace (pcap), and have to manually gather leads to find out what exactly is going on in it. I have tried different ways to automate the analysis part, and will share what I ended up with.\n\nI'll show my little tools that I played with to trace and visualize GSM network activity.\nImmature as all of it is, maybe it is interesting to share and form a vision of a helpful tool.\n\nFor example, when the task is to find out: at which network edge of a call leg do the RTP packets drop.\nFirst I need to know the chain of RTP ports that one particular subscriber uses.\nThen I need to count RTP packets arriving at each of them.\n\nAnother example, there are a bunch of {PFCP,MGCP} conversations, setting up the user plane vectors.\nAre all the ports configured correctly? I have to read through the entire {PFCP,MGCP} session to overlay all the bits that form the final result.\n\nAnother example, in a very active network, a particular voice call has a problem. How do I efficiently examine only those packets that are directly related to this particular TMSI / IMSI / RTP packet / RSL-ChanRef / ...","original_language":"eng","persons":["Neels Hofmeyr"],"tags":["osmodevcon2024","195","2024","osmodevcon2024","osmocom"],"view_count":106,"promoted":false,"date":"2024-05-04T18:15:00.000+02:00","release_date":"2024-06-01T00:00:00.000+02:00","updated_at":"2026-02-10T23:45:06.512+01:00","length":1295,"duration":1295,"thumb_url":"https://static.media.ccc.de/media/conferences/osmodevcon/2024/195-6afe9919-dd80-507d-8ab6-16df8e487920.jpg","poster_url":"https://static.media.ccc.de/media/conferences/osmodevcon/2024/195-6afe9919-dd80-507d-8ab6-16df8e487920_preview.jpg","timeline_url":"https://static.media.ccc.de/media/conferences/osmodevcon/2024/195-6afe9919-dd80-507d-8ab6-16df8e487920.timeline.jpg","thumbnails_url":"https://static.media.ccc.de/media/conferences/osmodevcon/2024/195-6afe9919-dd80-507d-8ab6-16df8e487920.thumbnails.vtt","frontend_link":"https://media.ccc.de/v/osmodevcon2024-195-my-hobby-dabbles-at-examining-network-traces","url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_title":"OsmoDevCon 2024","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024","related":[],"recordings":[{"size":117,"length":1295,"mime_type":"video/webm","language":"eng","filename":"osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_webm-sd.webm","state":"new","folder":"webm-sd","high_quality":false,"width":720,"height":576,"updated_at":"2024-06-03T06:28:04.449+02:00","recording_url":"https://cdn.media.ccc.de/events/osmodevcon/2024/webm-sd/osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_webm-sd.webm","url":"https://api.media.ccc.de/public/recordings/77855","event_url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024"},{"size":74,"length":1295,"mime_type":"video/mp4","language":"eng","filename":"osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_sd.mp4","state":"new","folder":"h264-sd","high_quality":false,"width":720,"height":576,"updated_at":"2024-06-03T06:12:03.612+02:00","recording_url":"https://cdn.media.ccc.de/events/osmodevcon/2024/h264-sd/osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_sd.mp4","url":"https://api.media.ccc.de/public/recordings/77853","event_url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024"},{"size":19,"length":1295,"mime_type":"audio/mpeg","language":"eng","filename":"osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_mp3.mp3","state":"new","folder":"mp3","high_quality":false,"width":0,"height":0,"updated_at":"2024-06-03T06:06:02.311+02:00","recording_url":"https://cdn.media.ccc.de/events/osmodevcon/2024/mp3/osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_mp3.mp3","url":"https://api.media.ccc.de/public/recordings/77852","event_url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024"},{"size":13,"length":1295,"mime_type":"audio/opus","language":"eng","filename":"osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_opus.opus","state":"new","folder":"opus","high_quality":false,"width":0,"height":0,"updated_at":"2024-06-03T06:05:17.613+02:00","recording_url":"https://cdn.media.ccc.de/events/osmodevcon/2024/opus/osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_opus.opus","url":"https://api.media.ccc.de/public/recordings/77851","event_url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024"},{"size":398,"length":1295,"mime_type":"video/webm","language":"eng","filename":"osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_webm-hd.webm","state":"new","folder":"webm-hd","high_quality":true,"width":1920,"height":1080,"updated_at":"2024-06-03T06:04:37.737+02:00","recording_url":"https://cdn.media.ccc.de/events/osmodevcon/2024/webm-hd/osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_webm-hd.webm","url":"https://api.media.ccc.de/public/recordings/77849","event_url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024"},{"size":323,"length":1295,"mime_type":"video/mp4","language":"eng","filename":"osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_hd.mp4","state":"new","folder":"h264-hd","high_quality":true,"width":1920,"height":1080,"updated_at":"2024-06-01T21:46:18.089+02:00","recording_url":"https://cdn.media.ccc.de/events/osmodevcon/2024/h264-hd/osmodevcon2024-195-eng-my_hobby_dabbles_at_examining_network_traces_hd.mp4","url":"https://api.media.ccc.de/public/recordings/77254","event_url":"https://api.media.ccc.de/public/events/6afe9919-dd80-507d-8ab6-16df8e487920","conference_url":"https://api.media.ccc.de/public/conferences/osmodevcon2024"}]}