Attach Flow InspectorRSP Lab

Checking your session…

12

Captures

148

Transactions

3

With a failure

2026-08-24

Latest

Upload a capture

Drop a .pcap here

Choose file

Captures12

attach-unknown-imsi.pcap ▲FAILED 4 tx

attach-complete-2026-08-24.pcap ●COMPLETE 7 tx

detach-reattach.pcap ●COMPLETE 11 tx

gtp-create-session.pcap ●COMPLETE 6 tx

Signalling flow4 messages

HSSsubscriber db

MMEcapture point

SGW-C / SMFsession

Authentication-Information-Request#14

Authentication-Information-Answer2001#16

Update-Location-Request#21

Update-Location-Answer5001#23

▲Flow halted — no GTPv2-C session was ever created

attach-unknown-imsi.pcap · uploaded 2026-08-24 09:12 UTC

Transactionstable view

Frame	Interface	Message	Direction	IMSI	Result
14	S6a	Authentication-Information-Request	request	001010123456789	—
16	S6a	Authentication-Information-Answer	answer	001010123456789	2001
21	S6a	Update-Location-Request	request	001010123456789	—
23	S6a	Update-Location-Answer	answer	001010123456789	5001

RSP Lab · Open5GS

Attach Flow Inspector

Upload a packet capture from Open5GS and read the attach or registration as a ladder, one lane per node, with each failure explained in plain words at the exact message where the flow stopped.

Drop a .pcap — dissection runs on its own, nothing to install
4G and 5G attach, EAP-AKA over SWm/SWx, IMS over Cx and SIP, TS.43 entitlement
Sample captures to open straight away, and a side-by-side compare of two flows
No capture yet? Make your own on a laptop in under an hour

No account yet? Ask for access — it is a lab, and visitors are welcome.

Signalling captures

Diameter (S6a, SWm, SWx, Cx), NAS, GTPv2-C, SIP and TS.43, dissected from packet captures. Upload a .pcap and it is analysed automatically. No capture? Open a SAMPLE, or make your own.

Upload a capture

Drop a .pcap here

Captures

loading…

Signalling flow

HSSsubscriber db

MMEcapture point

SGW-C / SMFsession

Compare with another capture

Pick a second capture to line the two flows up step by step, e.g. a success against a failure of the same procedure.

Transactionstable view

failures only

Frame	Interface	Message	Direction	IMSI	Result