GPRS challenges mobile network operators.The path from 2G to 3G mobile communications contains four crucial steppingstones.
General packet radio service (GPRS (General Packet Radio Service) The first high-speed digital data service provided by cellular carriers that used the GSM technology. GPRS added a packet-switched channel to GSM, which uses dedicated, circuit-switched channels for voice conversations. ) networks are an example of the new challenges in the test field for network operators. GPRS is an important improvement on the path from second- to third-generation (3G) mobile communications systems. An overlay to existing global system for mobile communications (communications) Global System for Mobile Communications - (GSM, originally "Groupe de travail Sp?ciale pour les services Mobiles") One of the major standards for digital cellular communications, in use in over 60 countries and serving over one billion subscribers. (GSM) networks, GPRS lays the foundation for universal mobile telecommunication service (UMTS (Universal Mobile Telecommunications System) The GSM implementation of the 3G wireless phone system. Part of IMT-2000, UMTS provides service in the 2 GHz band and offers global roaming and personalized features. ) and 3G systems that are based on packet-switched architectures.
To support the new features introduced by GPRS, the existing GSM network must be enhanced with the addition of a new set of network elements, such as packet control unit (PCU PCU - PCI Configuration Utility ), the serving GPRS support nodes (SGSN SGSN Serving GPRS Support Node ) and the gateway GPRS support nodes (GGSN GGSN Gateway GPRS Serving/Support Node
GGSN Gateway General Support Node (packet radio service)
GGSN Gateway Gprs Support Node
GGSN General Gprs Serving Node ). This new system is totally based on a packet-switched approach, and it is usually linked to other packet data networks like the Internet, X.25 network or other GPRS networks.
Monitoring, performance testing Performance Testing covers a broad range of engineering or functional evaluations where a material, product, or system is not specified by detailed material or component specifications: Rather, emphasis is on the final measurable performance characteristics. , simulation and emulation are crucial steps in the process of verifying the functionality and efficiency of individual GPRS network elements or an operator's entire network. The new requirements added by the GPRS layer introduce new challenges for operators. In particular, each element must be verified for interoperability. The combination and interworking (standard) interworking - Systems or components, possibly from different origins, working together to perform some task. Interworking depends crucially on standards to define the interfaces between the components. of network elements and new features require new tests, which must cover the following:
* extended protocols on eight different signaling, and six different combined signaling and data interfaces inside the GPRS system;
* monitoring on multiple interfaces with different protocol stacks to obtain an overview of the whole system;
* simulation, emulation, data generation and analysis of multiple interfaces and protocol stacks;
* performance measurements;
* finding problems caused by the mobility in PDNs, for example, changing bandwidth on the air interface and its subsequent influence on the TCP/IP TCP/IP
in full Transmission Control Protocol/Internet Protocol
Standard Internet communications protocols that allow digital computers to communicate over long distances. connection performance; and
* interworking or circuit-switched and packet-switched network components on, for example, location updates and short message services.
Test requirements fall into four areas:
1 Physical-layer testing: Most testers designed for physical-layer testing also contain protocol display and testing for Layer 2.
2 Circuit-switch testing: Seeing the signaling protocols and checking the switched circuits is necessary.
3 Packet-switched testing: This can be separated into the testing of the network layers (up to Layer 3 in the ISO (1) See ISO speed.
(2) (International Organization for Standardization, Geneva, Switzerland, www.iso.ch) An organization that sets international standards, founded in 1946. The U.S. member body is ANSI. OSI model).
4 Interworking between circuit-switched and packet-switched networks should also be checked.
The ideal protocol test system for GPRS should include all physical interfaces and all Layer 2 variants; all protocols for GSM and GPRS; the ability to monitor and simulate multiple interfaces in parallel because of the system's complex behavior; and the ability to monitor a particular condition in the network, trace it and make it available as a predefined configuration for easy and effective simulation test in the test plant.
The recommended test platform should include monitoring and simulation tools, combined with emulation and packet generation and checking capabilities. Due to the GPRS network environment, a standard interface to user applications with IP data is also recommended.
Because GPRS is the most important step to the UMTS 3G system, the protocol tester must be ready to address this technology. In particular, the protocol test instrument will have to be able to handle asynchronous transfer mode See ATM.
(communications) Asynchronous Transfer Mode - (ATM, or "fast packet") A method for the dynamic allocation of bandwidth using a fixed-size packet (called a cell).
See also ATM Forum, Wideband ATM.
Indiana acronyms. (ATM) exchanges with different interfaces, since the ATM interface will be incorporated into GPRS as the basic connection for UMTS.
Higher data transmission rates will also be achieved in next-generation systems by enhanced data rates for GSM evolution
Enhanced Data rates for GSM Evolution (EDGE) or Enhanced GPRS (EGPRS), is a digital mobile phone technology that allows it to increase data transmission rate and improve data transmission reliability. . UMTS increases speed and combines communications services, such as terrestrial mobile communications, wireless local loop, satellite-based mobile communications and wireless multimedia services.
When taking a look at the future and at 3G networks, a protocol tester will have to be able to handle higher bandwidths with new transport technologies like ATM, extended interworking features, and such new services as wireless multimedia applications. With the current and expected issues associated with GPRS protocol testing, mobile network operators need instruments that will provide both for the future and the here and now.
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