Cisco Cisco Packet Data Gateway (PDG)
SaMOG Gateway Overview
SaMOG Features and Functionality - Base Software ▀
SaMOG Administration Guide, StarOS Release 19 ▄
61
Step
Description
2.
The WLC forms an Access-Request message with the EAP-Identity payload, User-Name and Acct-Session-Id, and sends
the same to SaMOG.
the same to SaMOG.
3.
SaMOG forms a Radius Access-Request or Diameter DEA message towards the AAA server using the attributes received
from the WLC.
from the WLC.
4.
The AAA server performs an EAP authentication and sends the Access-Challenge/DEA to SaMOG with the EAP payload.
5.
SaMOG copies the EAP payload to the Access-Challenge message towards the WLC.
6.
The WLC sends an EAP Request towards the UE.
7.
The UE sends an EAP response.
8.
The WLC sends the Access-Request to SaMOG with the EAP payload received from the UE.
9.
SaMOG sends the Access-Request/DER to the AAA server with the EAP payload.
10.
The AAA server fetches the subscriber profile from HLR/HSS and validates the EAP Challenge response sent from the UE.
The Access-Accept/DEA is sent to SaMOG with the user profile and EAP Success payload. SaMOG saves the user profile
information.
The Access-Accept/DEA is sent to SaMOG with the user profile and EAP Success payload. SaMOG saves the user profile
information.
11.
SaMOG performs DNS procedures towards the DNS server to get the P-GW/GGSN IP address.
12.
SaMOG sends a create request (GTPv2 or GTPv1) towards the P-GW/GGSN (or local P-GW/GGSN in case of LBO) and
receives the IP Address of the UE in response (IP@G).
receives the IP Address of the UE in response (IP@G).
13.
SaMOG sends Access-Accept to the WLC with EAP-Success payload.
14.
The WLC sends EAP-Success to the UE.
15.
The UE performs DHCP with the WLC and obtains the IP address (IP@W).
16.
The WLC sends an Accounting Start Req with the Framed-IP-Address value (IP@W).
If the Accounting Server is configured at SaMOG (SaMOG acting as an Accounting Proxy), the Accounting Start Req is
forwarded to the Accounting server.
If the Accounting Server is configured at SaMOG (SaMOG acting as an Accounting Proxy), the Accounting Start Req is
forwarded to the Accounting server.
17.
SaMOG creates a NAT entry between the IP@W and IP@G.
18.
The UE sends/receives data packets with the IP address (IP@W) over the 802.11 interface towards/from the Access Point
(AP), and the AP sends/receives data packets over CAP/WAP to/from WLC or intermediate routers. The WLC or the
intermediate routers will forward/receive data packets as plain IP towards/from SaMOG.
(AP), and the AP sends/receives data packets over CAP/WAP to/from WLC or intermediate routers. The WLC or the
intermediate routers will forward/receive data packets as plain IP towards/from SaMOG.
19.
SaMOG performs NAT, changing the IP from IP@W to IP@G, and forwards the IP packets over GTP-u tunnel towards the
P-GW/GGSN (Local P-GW/GGSN in case of LBO). Also, reverse NATing (IP@G to IP@W) occurs when the data is
received from the P-GW/GGSN in the GTP-u tunnel and forwarded to the UE.
P-GW/GGSN (Local P-GW/GGSN in case of LBO). Also, reverse NATing (IP@G to IP@W) occurs when the data is
received from the P-GW/GGSN in the GTP-u tunnel and forwarded to the UE.
Limitations, Restrictions, and Dependencies
This section identifies limitations, restrictions, and dependencies for the SaMOG WAG integration:
The AP location is sent from the WLC in the Called-Station-Id attribute. The WLC may include either the AP
MAC, AP Name, AP MAC and SSID, or AP Name and SSID. If the WLC is configured to send the AP Name
(for sending ULI on Gn interface), SaMOG will not be able to send the AP MAC in TWAN Identifier AVP
over the S2a interface.
(for sending ULI on Gn interface), SaMOG will not be able to send the AP MAC in TWAN Identifier AVP
over the S2a interface.