Telecommunications Networking ITelecommunications Network ManagementSlide 3Slide 4Slide 5Operations Support Systems (OSS’s)Telecommunications Management Networks (TMN)A Classic Traffic Engineering ProblemThe Poisson (Random) ProcessSlide 10ExampleExample (Cont’d)Service Creation EnvironmentService Creation ExampleCopyright 1998, S.D. Personick. All Rights Reserved.Telecommunications Networking ILecture 18Telecommunications Network ManagementCopyright 1998, S.D. Personick. All Rights Reserved.Telecommunications Network Management•Some questions to ask if you are thinking of becoming the owner/operator of a large telecommunications network:-How do I characterize the quality of service I will provide in a way that can be measured and engineered into my networks; and in a way that my customers will find usefulCopyright 1998, S.D. Personick. All Rights Reserved.Telecommunications Network Management•Some questions to ask if you are thinking of becoming the owner/operator of a large telecommunications network:-How will I ensure that I have enough network capacity to provide my customers with a specified, quantifiable quality of service…but not more network capacity than what is required to do soCopyright 1998, S.D. Personick. All Rights Reserved.Telecommunications Network Management•Some questions to ask if you are thinking of becoming the owner/operator of a large telecommunications network:-How do I activate services for customers without having to send technicians out to the customers’ premises (service activation)-How do I monitor each customer’s quality of service (service assurance)Copyright 1998, S.D. Personick. All Rights Reserved.Telecommunications Network Management•Some questions to ask if you are thinking of becoming the owner/operator of a large telecommunications network:-How to I monitor the current state (configuration, alarm conditions, and usage measurement data) of my network equipment; and how can my network automatically recover from various fault conditionsCopyright 1998, S.D. Personick. All Rights Reserved.Operations Support Systems (OSS’s)•Operations Support Systems (OSS’s), not to be confused with operating systems, are complex computer applications which are used to automate many of the tasks that were done manually, in telecommunications systems, a few decades ago.•The objectives are to increase responsiveness to customers needs, and to reduce cost•Similar to networked information systems in other industriesCopyright 1998, S.D. Personick. All Rights Reserved.Telecommunications Management Networks (TMN)Enterprise Management SystemsService Management SystemsNetwork Management SystemsElement Management SystemsNetwork ElementsSecurityBillingTraffic Mgmt/QOSConnectivityRedundancyRouting...Copyright 1998, S.D. Personick. All Rights Reserved.A Classic Traffic Engineering Problem1NLinesTrunks1M<NConcentratorErlang’s formulas (queuing theory)Copyright 1998, S.D. Personick. All Rights Reserved.The Poisson (Random) Processx x x x x xThe probability of an “event” in any small interval of length dt (seconds) is dt, where “ ” is called the intensity of the Poisson random process. The occurrence of “events” in any interval is statistically independentof the occurrence of “events” in any other disjoint intervalEventsTime Copyright 1998, S.D. Personick. All Rights Reserved.The Poisson (Random) Processx x x x x xThe probability of N “events” in an interval of lengthT seconds is Events!/ NeN Where is TCopyright 1998, S.D. Personick. All Rights Reserved.ExampleSuppose there are 100 telephone lines connected to a concentrator with M outgoing trunks. Each telephoneline generates calls (events) approximately as a Poisson process, at an intensity of 3 calls per hour; and each call lasts exactly 3 minutes. (Clearly a simplification)How many outgoing trunks, N, do we need to ensure the probability of “all trunks busy” at any given timeis less than .01?“All trunks busy” would occur if we had M or more “events” in the last 3 minutesCopyright 1998, S.D. Personick. All Rights Reserved.Example (Cont’d)Probability of “all trunks busy” = !/ NeMNWhere =300 x 3/60 = 15< .01Answer M = 26Copyright 1998, S.D. Personick. All Rights Reserved.Service Creation EnvironmentSwitchSTPISCP (data + callprocessing)Intelligent Peripheral (IP)SCENon-real-time downloadCopyright 1998, S.D. Personick. All Rights Reserved.Service Creation Example•Customer Switch SCP IP off-hook Prov inst Play announcement # 1 “Please enter you access pin number” Collect 5 digits 54321# Authenticate OK Play announcement # 2 “Please enter the number you are calling, now” 1 215 895 6208 Process call Call
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