MAPS™ GSM AoIP Emulator
(Scripted GSM A over IP Emulation)
Background
The above diagram depicts some of the internals of the GSM network. One of the main advantages of having IP based A-interface for the user
plane is a much more flexible network design between the BSS and the CS core.
BSS over IP involves Gb and A interface over IP. For A interface over IP, control plane signaling over IP (SIGTRAN) has been introduced in 3GPP
Release 7 while certain features (e.g. MSC in Pool and Layered Architecture) require an intermediate signaling network for best performance.
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A interface user plane adaptability for IP based transport allows it to take full advantage of IP based technologies. The IP based transport protocols
provide a low cost intermediate network and simplify the implementation of MSCs in a pool.
The GSM network can be divided into following broad parts.
- The Mobile Station (MS)
- The Base Station Subsystem (BSS)
- The Network Switching Subsystem (NSS)
- The Operation Support Subsystem (OSS)
Overview
GL’s Message Automation & Protocol Simulation (MAPS™) is an advanced protocol simulator/tester capable of generating traffic and simulating
GSM A over IP. MAPS™ GSM AoIP designed for Air interface can simulate BSC (Base Station Controller), and MSC (Mobile Switching Center) entities.
The application is available as
- MAPS™ GSM AoIP (Item #PKS137) for GSM A over IP
MAPS™ is also capable of simulating GSM A and GSM Abis interface over TDM, along with various other suite of protocols, refer to
MAPS™ webpage for the list of supported protocols.
The application gives the users the unlimited ability to edit BSSMAP and DTAP messages and call scenarios (message sequences). "Message sequences"
are generated through scripts. "Messages" are created using message templates.
MAPS™ GSM AoIP supports send/receive SMS (Short Message Service) simultaneously using signaling channel with the voice/data/fax service over
a GSM network.
Possible applications include:
- Complete analysis and simulation capability on par with any protocol tester in the market
- Provides fault insertion, and erroneous call flows testing capability
- Functional testing, Regression testing and Conformance testing of network elements
- Ready scripts makes testing procedure simpler, less time consuming and hence time to market products.
Main Features
- GSM A simulation over IP
- GSM AoIP Emulator can be configured to act as either BSC or MSC
- Supports transmission and detection of RTP traffic - digits, voice file, single /dual tones
- User-friendly GUI for configuring the SCTP Layer
- User configurable signaling links
- Supports all Call Control, Mobility Management, Radio Resource Management messages, and SMSes (Short Message Service)
- Access to all BSSMAP and DTAP message parameters like TMSI, IMSI, CIC, MCC, LAC, and more
- User controlled access to optional parameters such as timers.
- Supports Authentication, TMSI Reallocation, Encryption, and other optional procedures
- Ready scripts for Mobile Originating, Mobile terminating, Location Updating procedures, and Mobile Originating and Terminating SMSes (Short Message Service)
- Logging of all messages in real-time
- Save and load configurations
- Supported on Windows® XP (or higher) operating systems
Supported Protocols Standards
UMTS IuCS Protocol Stack
The BSS communicates with the Network Service Switching center across the A interface. At the MSC, the information is mapped across the A interface
to the SCTP Layer from the BSC. Here, the equivalent set of radio resources is called the BSS MAP. The BSS MAP/DTAP and the MM and CM are at the upper
layers of Layer 3 protocols. This completes the relay process. Through the control-signaling network, the MSCs interact to locate and connect to users
throughout the network.
| Available Standards |
Supported Protocols |
Specification Used |
GSM AoIP
3GPP TR 43.903 V9.0.0 (2009-12) |
SCCP |
Q.713, CCITT (ITU-T) Blue Book |
| SCTP |
RFC 4960 |
| M3UA |
RFC 3332 |
| BSSMAP/DTAP |
3GPP TS 08.08 V8.9.0, 3GPP TS 48.008 V10.0.0 (2011-01) |
| MM / CC |
3GPP TS 04.08 V7.17.0 |
| RR |
3GPP TS 04.18 V8.13.0 |
| SMS |
3GPP TS 03.40 V7.5.0 & 3GPP TS 04.11 V7.1.0 GSM 03.38 version 7.2.0 Release 1998 |
Test Configuration
This feature allows users to configure the necessary parameters to establish communication between MAPS™ GSM AoIP and the DUT. GSM A over IP
interface supports SCTP configuration.
Screenshot of GSM AoIP Testbed Setup Configuration
Call Generation
Call Generation option allows the user to simulate outgoing communications where an outgoing call is initiated by sending call control messages using
proper scripts and profiles. The profile allows necessary parameters of call control messages to be changed during runtime.
Mobile Originating Call Flow (MOC)
Screenshot of Mobile Originating from BSC to MSC Call Flow
Here, MAPS™ GSM AoIP is configured to act as BSC, and test the DUT (MSC) that is configured to accept incoming calls and SMSes. MAPS™
GSM AoIP initiates the messages towards MSC and responds to messages from BSC.
MAPS™ GSM AoIP as BSC
The test is performed to ensure that the MAPS™ (BSC) sends CM SERVICE REQUEST to DUT (MSC) in order to establish SCCP connection over which
MM connection will be established. The DUT (MSC) responds with ”CC Connection Confirm” message for a successful SCCP connection. The MSC end initiates
authentication and may start the ciphering mode setting, Identification and TMSI Reallocation procedures as depicted in the figure.
MOC Call Generation at BSC Node
Location Updating Call Flow (LUC)
Screenshot of Location Updating from BSC to MSC Call Flow
The test is performed to ensure that the MAPS™ (BSC) sends LOCATION UPDATING REQUEST message to DUT (MSC) which replies with a CC
connection confirm message in response. The MSC end initiates authentication and may start the ciphering mode setting, Identification and TMSI Reallocation
procedures as depicted in the figure.
LUC Call Generation at BSC Node
Mobile Terminating Call Flow (MTC)
Screenshot of Mobile Terminating from MSC to BSC Call Flow
Here, MAPS™ GSM AoIP is configured to act as MSC, and test the DUT (BSC) that is configured to accept incoming calls and SMSes. MAPS™
GSM AoIP initiates the messages towards BSC and responds to incoming messages.
MAPS™ GSM AoIP as MSC
The test is performed to ensure that the MAPS™ (MSC) sends PAGING request message to DUT (BSC). The BSC end replies with PAGING RESPONSE
message and initiates authentication, ciphering mode setting, Identification and TMSI Reallocation procedures.
MTC Call Generation at MSC Node
Call Reception
Call Reception is capable of handling all possible incoming signaling and call control messages and responding to the call requests.
- Automatic response to incoming messages - Processes the BSSMAP and DTAP messages received based on the script specified in the script configuration window
- Provide the result of the test with detail protocol decode and ladder diagram
Incoming Call Handler feature has an option to pre-set the required scripts for the test, which can automatically detect call generated from other entity.
Screenshot of incoming Call Handler Window
Mobile Originating Call Flow (MOC)
This test is performed to ensure that the MAPS™ (configured as MSC) in order to initiate Authentication process, sends Authentication Request
message as response to Attach Request from BSC (DUT).
Mobile Originating Call Flow (MOC) at the MSC Node
Location Updating Call Flow (LUC)
This test is performed to ensure that the MAPS™ (configured as MSC) in order to initiate Authentication process, sends Authentication Request
message as response to LOCATION UPDATING REQUEST from BSC (DUT).
Location Updating Call Flow (LUC) at the MSC Node
Mobile Terminating Call Flow (MTC)
This test is performed to ensure that the MAPS™ (configured as BSC) sends PAGING RESPONSE for the request message. MSC end initiated the
Authentication process, for which the BSC (MAPS™) responds with AUTHENTICATION RESPONSE message.
Mobile Terminating Call Flow (MTC) at the BSC Node
Bulk Call Simulation
MAPS™ GSM AoIP supports Bulk Call Simulation and Stress/Load Testing capabilities through Load Generation feature. Load Generation window
helps users configure Stress/Load Testing parameters such as Call per second (CPS) or Busy hour call attempts (BHCA), Max Simultaneous Calls and Burst
parameters.
Screenshot of Load Generation Parameters
Customization of Call Flow and Messages Using Pre-Processing Tools
- Script Editor - The script editor allows the user to create / edit scripts and to define variables for the protocol fields. The script uses pre-defined
message templates to build call flow and perform send and receive actions. Script editor provides options to run the test for multiple iterations in sequential
or random flow. Commands allow retransmission of messages with specific interval
Screenshot of Script Editor
- Profile Editor - Profiles are used to provide the user configured values to the fields in the Messages (i.e, Message Template in MAPS™
GSM AoIP) through variables which are going to change during the course of a call.
Screenshot of Profile Editor
- Message Editor - The Message Template is a *.HDL file that comprises of protocol encoding parameters with preset values. It is required to
create a message template for every message in a protocol. The message templates are called within the scripts to perform scenario based testing.
Screenshot of Message Editor
Call Flow & Script Execution Control
Message Sequence - MAPS™ GSM AoIP provides protocol trace with full message decoding, custom trace, and graphical ladder diagrams of
call flow with time stamp while simulation is running. Call flow graph allows to easily verify the messages exchanged between MAPS™ GSM AoIP and DUT.
See Call Generation and Call Reception for details
Script Contents & Script Flow - The Scripts Contents window displays the contents of the script selected for call generation or reception. The
Script Flow window displays the set of statements successfully executed by MAPS™ GSM AoIP to help users in troubleshooting a particular the call
scenario.
Events & Event Profile Editor - User-defined events allow redirection of script execution on-the-go. The custom parameters in the events can
also be changed during script execution using Event Profiles
Screenshot of Script Contents and Script Flow
Screenshot of Event Config
Call Statistics, Events, Link Status
Call Statistics & Status - By default, all call handling scripts (irrespective of the type of the functions) are assessed by MAPS™ GSM AoIP to
provide statistical information about total calls, active calls, completed calls, passed calls, and failed calls. It is also possible to characterize the statistical
information under different groups of call handling scripts under a unique heading.
In addition, Call Generation and Call Reception windows provide useful call status & script execution results.
Screenshot of Call Statistics and Status
Events Reporting – MAPS™ GSM AoIP provides Event Log, Error Events, and Captured Errors windows that log the captured events and
errors encountered during the progress of the call.
Screenshot of Event Log
Link Status - Link Status window indicates transport related information of the protocol, for example, if SCTP is used as transport, it indicates
if the Association is up or Down in the Link Status window.
Screenshot of Link Status
Buyer's Guide:
Specifications are subject to change without notice.
Back to Message Automation & Protocol Simulation Index Page
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