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What does that mean? IP of the original NAS packet?

I have 2 interfaces towards the network.

____________________________________________________________________________ Radius Client --> Radius Proxy 192.168.1.2 192.168.1.3 192.168.14.3 --> IPS1(192.168.14.4) 192.168.24.3 --> IPS2(192.168.24.4) ____________________________________________________________________________

Steps: 1)Radius Client ---> Send packet with NAS-IP-Address = 192.168.1.2 towards Radius Proxy. 2)Radius Proxy changes NAS-IP-Address with 192.168.14.3 for IPS1(or 192.168.24.3 for IPS2) and sends it.

You say that changing NAS-IP-Address the packet is transmitted correctly. Right?

From 192.168.14.3 to IPS1(192.168.14.4) if NAS-IP-Address = 192.168.14.3 From 192.168.24.3 to IPS1(192.168.24.4) if NAS-IP-Address = 192.168.24.3

Yes. Proxy server will change NAS-IP-Address from the original NAS address into it's own. That is OK.

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That's in internal attribute Packet-Src-IP-Address.

Should I modify this attribute or FreeRadius associates Packet-Src-IP-Address = NAS-IP-Address.

No, Packet-Src-IP-Address has the originating IP address for the radius packet (in your case it will be 192.168.1.2). If ISP needs to know the original NAS IP they should look in Packet-Src-IP-Address. Ivan Kalik Kalik Informatika ISP