GTP'(3.0)
This section describes the GTP' agent. This is a collection agent for real-time workflow configurations.
The GTP' agent collects messages and datagrams with charging protocol of type GTP' from GSM agents. By collecting this information the GTP' agent enables  to act as a Charging Gateway device, providing Charging Gateway Functionality (CGF) within UMTS/GPRS networks.
UMTS/GPRS Charging Gateway Functionality is Supported
The GTP' agent awaits initialization from the GSN nodes of the types SGSN and GGSN. When initiated, there are two protocols with which the Agent can interact with the nodes:
Transmission Control Protocol(TCP), and
Datagram Protocol(UDP)
A GTP' workflow can alternate implementation of two different protocols by using two GTP' agents. One for each protocol.
In case of failure, the GTP' agent can be configured to notify the GSN nodes to route the incoming data to another host. An alternative configuration is to set up a second and identical workflow, on a separate EC. The agent counts the received requests and publishes those values as MIM values. Those MIM values can also be viewed from the commandline tool with the wfcommand printcounters
 command.
The GTP' agent supports IPv4 and IPv6 environments.
Interaction Scenario
The following scheme demonstrates the message and data transfer between the GSN nodes and the GTP' agent when using UDP:
Â
When started, the GTP' agent sends aÂ
Node Alive Request
 message to all configured GSN nodes.
ÂThe GTP' agent awaits aÂ
Node Alive Response
 and will transmitÂNode Alive Request
 repeatedly, according to the Advanced tab settings. For further information see Advanced Tab in GTP' Agent Configuration(3.0).
ÂAfter a successfulÂ
Node Alive Response
 the GSN node starts to transmit Data record Transfer Requests to the agent. When safely collected, the agent replies with a Data record transfer Response.
ÂWhen the workflow is stopped, the messageÂ
Redirection Request
 is automatically sent to all configured GSN nodes. The workflow will not stop immediately, but waits for aÂRedirection Response
 from each of the GSN nodes. If the Max Wait for a Response (sec) value is exceeded, the workflow stops, regardless of whetherÂRedirection Response
 from the GSN nodes has been received or not.Note!
When using TCP, the behavior is different. For further information see GTP' Agent MZSH Commands, Events and Limitations(3.0).
Prerequisites
The reader of this information should be familiar with:
- GPRS Tunneling Protocol (GTP) across the Gn and Gp Interface [3GPP TS 29.060 V4.2.0]:http://www.3gpp.org/ftp/Specs/archive/29_series/29.060/29060-420.zip
Call and event data for the Packet Switched (PS) domain [3GPP TS 32.015 V3.11.0]: http://www.3gpp.org/ftp/Specs/archive/32_series/32.015/32015-3b0.zip
The section contains the following subsections:
- GTP' Agent Preparations(3.0)
- GTP' Agent Configuration(3.0)
- GTP' Agent Input/Output Data and MIM(3.0)
- GTP' UDR(3.0)
- GTP' Agent MZSH Commands, Events and Limitations(3.0)
- Handling of UDP Traffic for GTP' Agent(3.0)