What information is needed for a mobile or CGNAT request?¶
title: "What information is needed for a mobile or CGNAT request?" card_id: "IP-078" status: "complete" source_document: "https://docs.google.com/document/d/1Tx585Og2eQzTfEvfxpPZAEuNSVqq_Lss2KplN2ZPLDQ/edit?usp=drivesdk"
What information is needed for a mobile or CGNAT request?¶
Where a provider uses CGNAT, many customers may share the same public IP address at the same time.
A request containing only the address and date may therefore produce several possible customers—or no usable result at all.
The provider needs enough information to identify one translation or network session.
Start with the complete public IP address exactly as recorded by the external service.
Provide the full date and the most precise timestamp available.
The time zone or UTC offset must be unambiguous.
Seconds can matter because translation records and source ports may be reused quickly.
The public source port is often the crucial additional identifier.
It must be the translated source port seen by the external platform—not the device’s private internal port and not the destination service port.
The protocol may also be required.
TCP source port 51,543 and UDP source port 51,543 aren't necessarily the same communication.
Some provider systems may also use the destination IP address and destination port when locating a session.
The exact requirements depend on the network and the records it retains, so the request should preserve all available connection fields rather than guessing which ones will matter.
The timestamp must describe the same event as the IP address and source port.
Combining an address from one log entry with a port or time from another can produce a false match.
If the source clock may be inaccurate, that uncertainty should be explained rather than hidden by supplying an artificially precise time.
Mobile attribution may also involve a network session, account or SIM rather than an ordinary fixed-line subscriber allocation.
Any result still has to be interpreted at that level.
A complete mobile or CGNAT request gives the provider the best chance of distinguishing one customer session from everybody else sharing the address.
It doesn't guarantee that the necessary logs exist, remain within retention or identify the handset or person using the connection.