A 'pen register' is also known as as a 'dial(l)ed number recorder (DNR):
https://en.wikipedia.org/wiki/Pen_register
"A pen register, or dialled number recorder (DNR), is an electronic device that records all numbers called from a particular telephone line."

Compare French and English versions of Canadian Parliament Hansard transcript, 27/10/2009:
https://www.noscommunes.ca/DocumentViewer/fr/40-2/chambre/se...
Le projet de loi C-46 mettrait à jour le mandat pour l'enregistreur des numéros de téléphone composés, qui permet actuellement à la police de savoir quels numéros ont été composés.

https://www.ourcommons.ca/DocumentViewer/en/40-2/house/sitti...
Bill C-46 would update the existing dial number recorder warrant, which currently allows police to obtain data relating to dialed telephone numbers.

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Note added at 3 hrs (2022-05-08 19:44:44 GMT)
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@Timothy: The extent to which you can use the same French translation for both English terms will depend on your context - and especially so if the context is legal because the law probably applies differently to each type of surveillance (see, for example, Sections A and B(2) here, referring to the US: https://cyber.harvard.edu/privacy/Introduction to Government... ).

I suggest you post 'trap and trace' as a separate question and see what colleagues suggest.

Note also that the Canadian reference is pretty ancient (2009) and makes specific mention of 'telephone numbers', whereas your question suggests a more-recent (and broader) context possibly including IP addresses, routing info, etc.

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Note added at 3 hrs (2022-05-08 19:57:17 GMT)
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@Timothy: IMHO neither "enregistreur graphique" nor "dispositif de traçage" would be a satisfactory translation for either of the English terms, because they don't convey anything about the 'purpose' of the device in the context of your ST. The phrase "un dispositif d’enregistrement d’impulsions électroniques entrantes et sortantes", mentioned in your question, is inappropriate for the same reason.

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Note added at 3 hrs (2022-05-08 20:02:45 GMT)
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@Timothy: There's a link on your page from glosbe.com that might help with 'trap and trace': https://glosbe.com/fr/en/enregistreur des numéros de télépho... - enregistreur des numéros de téléphone reçus
Th problem with globsbe.com is the lack of information about the sources of those translations.