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ATM/IP in P613 End-to-End Service Testing Paola PARISE (CSELT) E-mail: paola.parise@cselt.it. Background. 1994: Memorandum of Understanding (MoU) for the availability of a European ATM Pilot PVC service Specification of Benchmark Services (Frame Relay, CBR, SMDS).
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ATM/IP inP613 End-to-End Service TestingPaola PARISE (CSELT)E-mail: paola.parise@cselt.it
Background 1994: Memorandum of Understanding (MoU) for the availability of a European ATM Pilot PVC service Specification of Benchmark Services (Frame Relay, CBR, SMDS) 1995: European ATM Pilot available for non commercial use P410 End-to-End Service Testing for Pan-European ATM Networks 1996: James (Joint ATM Experiment on European Service) is responsible of the maintenance of the platform that was the ATM Pilot James and national ATM networks usable for international end-to-end service experimentation P613 Methods and Tools for B-ISDN and N-ISDN Integration Testing
Methods and Tools for B-ISDN and N-ISDN Network Integration Testing P613 Project Leader Marco Vecchiato CSELT
AU Post und Telekom Austria AG CH Swiss Telecom PTT DT Deutsche Telekom AG, Germany HT Matav HTC Ltd. IT CSELT/STET, Italy PT Portugal Telecom S.A., Portugal RB Belgacom, S.A. de Droit Public TE Telefonica de Espana S.A., Spain Project Structure Project budget: 18 MM Project start date: 10/9/96 Project completion date: 30/9/98
M T1 A T2 B transit network T1 A T2 B Node-to-Node and End-to-End Test Suites Network Under Test access protocol network protocol
ATM service testing B-ISDNend-to-end (including interworking with N-ISDN) B-ISUPnode-to-node (including interworking with N-ISUP) IP over ATM FR interworking Narrowband service interworking testing GSM N-ISDN POTS Validation through a test execution experiment Main objectives of EURESCOM P613
The project develops for each type of service a well defined set of documents: Test Suite Structure and Test Purposes (TSS&TP), Implementation Conformance Statement and Implementation eXtra Information for Testing (ICS&IXIT), Abstract Test Suite (ATS). The ATS (the main technical document) can be written in TTCN or described by other means. Several test sessions will be performed to validate the project results in a real environment (e.g. international networks or experimental contexts) Test methodology
IP over ATM Service Specification Somebody knows how IP has to be transported over an ATM SVC Network ... IP switching (IETF RFC 1953, 1954, 1987Informational) Classical IP over ATM (IETF RFC 1577) NHRP (IETF) Tag Switching (IETF RFC 2105 Informational) I-PNNI (ATM Forum) MPOA (ATM Forum) MPOA Almost stable specification issued by ATM Forum Support of MPOA is foreseen in 1997 by many manufacturers Incorporates NHRP Project results will be baselines for testing specification on other service configuration
Following ATM Forum MPOA (Multiprotocol over ATM) Specification, the project will issue Functional Abstract Test Suite (Is the IP datagram delivered?) Performance Abstract test Suite (How fast, reliable the IP datagram delivery is?) P613 IP over ATM End-to-End Service Testing
MPOA Server PCO 2 PCO 3 PCO 1 MPOA Client MPOA Client ATM Service reference configuration PCO: Point of Control and Observation MPOA: MultiProtocol Over ATM
How QoS Measurement is Approached in P613: Performance Testing (1) • Benchmark methodology issued by IETF BMWG (Benchmark Methodology Working Group) in Request for Comment RFC 1944 • Throughput (Maximum rate at which none of the offered frames are dropped by the network) • Packet Loss Ratio (Maximum rate at which none of the offered frames are dropped by the network) • Latency (The one-way network latency is the time interval starting when the last bit of the input frame reaches the input port and ending when the first bit of the output frame is seen on the output port of the network) • Back to Back capacity(The back-to-back capacity measurement uses fixed length frames presented at a rate such that there is the minimum legal separation for a given medium between frames over a short to medium period of time, starting from an idle state)
How QoS Measurement is Approached in P613: Performance Testing (2) • Benchmark Applications: • Ping • FTP • Spray • Videoconferencing • Server Specific Performance Measurement: • ATM address resolution is always achieved by means of Servers that could be the bottlenecks of service performance. It is therefore useful to measure • time needed to reply to a query • number of simultaneously active shortcuts • ...
Performance Testing (3) Other Parameters % Service Unavailability due to ATM impairment % outages due to Server unavailability ... New! IETF BMWG is working on IPPM (IP Provider Performance Metrics) for the definition of Benchmark tools to measure service outages and other relevant parameters.
IETF Issll (Integrated services over specific lower layer) is defining the modalities of mapping an IP service class into an ATM SVC. Empirical approach could help: Analytical approach could help Thr, Flr, Lat =f(CLR, CER, CDT,CDV, Tset-up, Trelease) CLR CER CTD Tset-up Trelease CDV THR FLR LAT Mapping ATM QoS into IP QoS
Open Issues and Future Work on Performance Testing • Difficulties in testing phase automation • Only few testing equipment implement the needed protocol stack • Simultaneous monitoring of underlying ATM layeris considered useful • Research Communities and Labs are working on distributed service monitoring and testing
Conclusions P613 perceives the need of performance measurement and is proceeding with the description of methodology to assess the QoS given to users. MPOA and other architectures that base QoS provision on the ATM/IP integration constitute a technological improvement. Commercial offerings should be based on guarantees of QoS to a customer. In this case a Resource Reservation Set-up mechanism (RSVP) that acts on Network Elements could be the only applicable solution. Once IP services become differentiated on a QoS basis other effort on service provisioning aspects should be done (i.e. accounting, acceptance policies, ...)