WO1993023962A1 - Procede de regulation du trafic dans un reseau de telecommunications - Google Patents

Procede de regulation du trafic dans un reseau de telecommunications Download PDF

Info

Publication number
WO1993023962A1
WO1993023962A1 PCT/GB1993/000972 GB9300972W WO9323962A1 WO 1993023962 A1 WO1993023962 A1 WO 1993023962A1 GB 9300972 W GB9300972 W GB 9300972W WO 9323962 A1 WO9323962 A1 WO 9323962A1
Authority
WO
WIPO (PCT)
Prior art keywords
exchange
trunk
threshold
network
routes
Prior art date
Application number
PCT/GB1993/000972
Other languages
English (en)
Inventor
Ian Barry Crabtree
Charles Arnold Swaine
Original Assignee
British Telecommunications Public Limited Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB929210173A external-priority patent/GB9210173D0/en
Priority claimed from GB929210172A external-priority patent/GB9210172D0/en
Application filed by British Telecommunications Public Limited Company filed Critical British Telecommunications Public Limited Company
Priority to JP5519990A priority Critical patent/JPH08500219A/ja
Priority to EP93910183A priority patent/EP0640269A1/fr
Publication of WO1993023962A1 publication Critical patent/WO1993023962A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/36—Statistical metering, e.g. recording occasions when traffic exceeds capacity of trunks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/64—Distributing or queueing
    • H04Q3/66—Traffic distributors

Definitions

  • NTM Near real-time network traffic management
  • BT' s trunk network in the United Kingdom currently handles approximately six million call attempts per hour during the busy periods which is equivalent to 1, 700 call attempts per second.
  • any networl- difficulties are detected and controlled as quickly a ⁇ possible.
  • difficulties are often encountered by network traffic managers due to abnormal traffic patterns which can be caused by events such as 'phone-ins, tele-votes and public holidays (for example Christmas Day and New Year's Eve/Day). In all these cases traffic in the network varies widely from the normal level, sometimes quite spectacularly, and the network must be controlled to maintain the best overall network performance.
  • BT' s Network Traffic Management System currently receives statistics on upwards of 37,000 routes from 490 exchanges in the UK every five minutes, which measurement period was chosen to be a long enough period to be able to obtain a statistically reliable measurement of the network performance whilst being short enough to allow effective real-time control of the network.
  • the information received by the NTMS is processed to provide CCITT recommended parameters.
  • the parameter values are compared with thresholds to determine if any difficulties exist on the monitored network elements.
  • the NTMS provides near real-time surveillance and monitoring of the network' s status and performance. It provides the network traffic managers with information to enable them take prompt action to control the flow of traffic to ensure the maximum utilization of the network in all situations.
  • the NTMS allows network traffic managers to look at the raw statistics as well as derived generic parameters and to compare traffic patterns over the last few measurement periods to isolate any trends.
  • An On-Line Traffic Information System takes the measurement of statistics from the NTMS system and processes them to provide summarised historical data for daily and weekly traffic patterns. This system allows the network traffic managers to examine historical traffic patterns to detect any radical shifts in traffic.
  • a data management system provides the network traffic managers with an up-to-date copy of the routing tables at all trunk exchanges. This information is used to check the routes to which calls can be routed, which controls are in force and the routing algorithms being used.
  • ACE All Circuits Engaged
  • a method of controlling a telecommunications network which includes at least one local exchange connected by routes to one or more parent trunk exchanges each being one of a plurality of trunk exchanges interconnected by trunk routes, is characterised in that the method comprises applying focused overload controls to the trunk exchanges of the network when the Bids per Circuit per Hour (BCH) along the primary traffic routes from a parent trunk exchange to the local exchange exceed a first threshold and the magnitude of a decrease in the average Answer Seizure Ratio (ASR) on the trunk primary traffic routes to the parent exchange over a measurement period exceeds a second threshold.
  • BCH Bids per Circuit per Hour
  • ASR Answer Seizure Ratio
  • a primary traffic route is the route first tried for a call in a network, all alternative routes then being secondary.
  • the BCH parameter gives a normalised indication of the number of call attempts down a particular route and will generally stay at a normal value well below the maximum BCH that can be handled by the exchanges under normal conditions but will tend to move to and above that value during a focused overload. These normal values provide a maximum expected BCH range of the routes in the network.
  • the BCH will also rise due to an increase in country ⁇ wide traffic to a large number of subscribers served by a given local exchange, for example when a disaster befalls an area, but this will not necessarily result in a focused overload if a sufficiently high number of calls continue to be connected.
  • the inclusion of the test of the ASR in the present invention serves to distinguish between these two scenarios.
  • the first threshold can be set according to the normal maximum expected value of the BCH parameter on the route that can be properly handled by the network. It has been found that in a focused overload the BCH parameter rises very sharply reaching a peak in the first five minutes followed by an exponential drop to the normal level over the following forty minutes.
  • the first threshold is towards the high end of the above maximum expected BCH range. In this case a value of 30 can be used.
  • the network can be controlled automatically on detection of the focused overload to apply the method of the present invention without the intervention of a network manager.
  • the focused overload controls to be applied to the network may be call gapping applied to the home trunk exchanges or to one or more of the far-end trunk exchanges of the local exchange, for example.
  • the focused overload controls can be removed, ie that the focused overload problem has been overcome. It has been found that it is satisfactory to remove the focused overload controls once the BCH from the home exchange to the local exchange falls below a fourth threshold, which threshold is preferably 5. Once it has been determined that the focused overload controls can be removed, the focused overload controls applied to the exchanges of the network are removed either by a network manager or automatically by a network controlling apparatus. In this way local focused overload controls can be overidden once it has been determined globally that the problem has been solved.
  • a method according to the second aspect of the present invention can be used advantageously, whether or not in combination with a method according to the first aspect of the present invention.
  • the advantage lies in the increased flexibility available. If call gapping is applied to the home trunk exchange, it has effect on all routes in to that home trunk exchange for the local exchange. If it is applied at the far-end trunk exchanges, it is possible to select one or more of the far-end trunk exchanges which is or are contributing heavily to the focused overload, and call gap only that one exchange, or those selected trunk exchanges. When applying call-gapping to one or more of the far- end trunk exchanges, a less sensitive test than that used for the application of local focused overload controls has been found to be appropriate.
  • the seventh threshold can conveniently be set to be about equal to the average normal ASR for exchanges in the network so the exchanges are regulated to allow the associated ASRs to move back to this value.
  • the fifth, sixth and seventh thresholds will in general need to be determined by analyzing the normal values for the particular network to be controlled in accordance with the above general principles.
  • the extent of call gapping applied can be a fixed amount, for example 5 second call gapping, but will preferably be selected according to the prevailing conditions based on prior knowledge of the call handling capability of the subscriber being called or from general experience of the network manager.
  • a telecommunications network comprises a number of digital main switch units (DMS ⁇ s) - trunk exchanges - of which only five are shown for clarity and are referenced 102, 104, 106, 108 and 110.
  • DMS ⁇ s digital main switch units
  • Subscribers' customer premises equipment of which only two are shown referenced 112 and 114, are connected to the trunk exchanges 102 to 110 via respective digital local exchange (DLE) 116 and 118.
  • DLE digital local exchange
  • the digital local exchange 116 may not be able to handle the calls and in extreme cases the DLE might also go into overload. This will block unrelated traffic in the area around the destination exchange. This is what is called a focused overload which needs to be controlled if congestion is to be avoided.
  • the run-time system 206 employs a three phase cycle in which recommendations for focused overload control actions are passed to the network traffic manager 208.
  • the run-time system 206 monitors each local exchange and determines when the BCH along the route from the home trunk exchange of a local exchange exceeds 30 and in which the BCH averaged over trunk primary traffic routes to that home exchange have increased by 40% since the last measuring period. When these conditions are satisfied the run-time system supplies a recommendation to the network traffic manager 208 to apply focus overload controls and in particular, in this embodiment, call gapping to the parent trunks of the local exchange or to far-end trunks of the local exchange affected - assumed for the purposes of the following description to be local exchange 116 of Figure 1.
  • the run-time system 206 can provide recommendations to the network traffic manager 208 on applying a specific, local focused overlaod controls to the trunk exchanges 102 to 110 to the network 202 according to the present invention.
  • the parent trunk exchange 102 of the local exchange 116 will be subjected to call gapping to numbers of the local exchange 116 once the ASR from the parent trunk exchange to the local exchange 116 has remained at less than 20% for the duration of a five minute measuring period and the BCH along the route from the parent trunk exchange to the local exchange 116 is greater than 10.
  • the run-time system 206 can alternatively recommend call gapping to numbers of the local exchange 116 at a far- end trunk exchange 106 to 110 of the local exchange 116 when the ASR along the route from the far-end trunk exchange to a parent exchange 102, 104 of the local exchange 116 falls below 45%.
  • the run-time system 206 can alternatively also recommend that all focused overload controls are removed once the BCH along the route from a local exchange' s home exchange to that local exchange is less than five. This ensures that all controls will be removed under a relevant, overriding condition. It is envisaged that the run-time system 206 may directly control the network to apply the method of the present invention as shown in Figure 3 but at present it is expected that it will be necessary to use a network traffic manager 208 to implement of the method of the present invention to allow overriding of the recommendations at his or her discretion.
  • the particular system employed was a QUINTUS PROLOG expert system run on a Sun Sparc station. Parameters generated during real network activity were recorded for the entire GB network for four, 5-minute measurement periods and stored as a data file on the computer.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Abstract

Procédé de régulation du trafic dans un réseau de télécommunications comprenant au moins un central local relié, par des voies d'acheminement, à au moins un central interurbain de rattachement, chaque central interurbain de rattachement faisant partie d'une pluralité de centres de rattachement reliés entre eux par des voies d'acheminement de rattachement. Ledit procédé consiste à exercer une régulation de surcharge concentrée sur au moins un central de rattachement du réseau lorsque les tentatives de prise par circuit et par heure (BCH) le long d'une voie primaire d'acheminement de trafic allant d'un central interurbain de rattachement au central local dépassent un certain seuil et que l'amplitude de diminution du taux de prise de réponse (TPR) moyen, sur la voie primaire d'acheminement de trafic interurbaine allant jusqu'au central de rattachement, dépasse, sur une période de mesure, un autre seuil. Les régulations de surcharge concentrées sont appelées régulations d'espacement d'appel, et la période de mesure dure approximativement cinq minutes.
PCT/GB1993/000972 1992-05-12 1993-05-12 Procede de regulation du trafic dans un reseau de telecommunications WO1993023962A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP5519990A JPH08500219A (ja) 1992-05-12 1993-05-12 遠隔通信網におけるトラフィックを制御する方法
EP93910183A EP0640269A1 (fr) 1992-05-12 1993-05-12 Procede de regulation du trafic dans un reseau de telecommunications

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GB929210173A GB9210173D0 (en) 1992-05-12 1992-05-12 Method of controlling a telecommunications network
GB9210172.4 1992-05-12
GB929210172A GB9210172D0 (en) 1992-05-12 1992-05-12 Method of controlling a telecommunications network
GB9210173.2 1992-05-12

Publications (1)

Publication Number Publication Date
WO1993023962A1 true WO1993023962A1 (fr) 1993-11-25

Family

ID=26300864

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1993/000972 WO1993023962A1 (fr) 1992-05-12 1993-05-12 Procede de regulation du trafic dans un reseau de telecommunications

Country Status (5)

Country Link
EP (1) EP0640269A1 (fr)
JP (1) JPH08500219A (fr)
CA (1) CA2135633C (fr)
SG (1) SG52408A1 (fr)
WO (1) WO1993023962A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5832064A (en) * 1996-05-30 1998-11-03 Electronics And Telecomunications Research Institute Mass calling processing method for televoting service
EP4404547A1 (fr) * 2023-01-17 2024-07-24 AVOXI, Inc. Surveillance proactive de numéro de téléphone sur la base d'un rapport de crise d'épilepsie de réponse

Non-Patent Citations (11)

* Cited by examiner, † Cited by third party
Title
ACKERLEY R. G.: "OVERALL GRADE-OF-SERVICE MODELS FOR THE BRITISH TELECOM NETWORK.", TELETRAFFIC SCIENCE FOR NEW COST EFFECTIVE SYSTEMS, NETWORKS AND SERVICES. TORINO, JUNE 1 - 8, 1988., AMSTERDAM, ELSEVIER., NL, vol. CONGRESS 12, 1 June 1988 (1988-06-01), NL, pages 16 - 27., XP000279756 *
CHEMOUIL P., FILIPIAK J.: "INTEGRATED NETWORK MANAGEMENT AND CONTROL.", COMPUTER NETWORKS AND ISDN SYSTEMS., NORTH HOLLAND PUBLISHING. AMSTERDAM., NL, vol. 20., no. 01 / 05., 1 December 1990 (1990-12-01), NL, pages 143 - 153., XP000161279, ISSN: 0169-7552, DOI: 10.1016/0169-7552(90)90020-S *
IEEE TRANSACTIONS ON COMMUNICATIONS vol. 29, no. 4, April 1981, NEWYORK pages 376 - 385 HAENSCHKE ET AL 'Network Management and Congestion in the U.S. Telecommunications Network' *
INTERNATIONAL SWITCHING SYMPOSIUM vol. 4, 15 March 1987, PHOENIX (US) pages 984 - 988 STACEY ET AL 'Dynamic alternative routing in the British telecom trunk network' *
KENICHI MASE, HISAO YAMAMOTO: "ADVANCED TRAFFIC CONTROL METHODS FOR NETWORK MANAGEMENT.", IEEE COMMUNICATIONS MAGAZINE., IEEE SERVICE CENTER, PISCATAWAY., US, vol. 28., no. 10., 1 October 1990 (1990-10-01), US, pages 82 - 88., XP000165759, ISSN: 0163-6804, DOI: 10.1109/35.60371 *
LANGLOIS F., REGNIER J.: "DYNAMIC CONGESTION CONTROL IN CIRCUIT-SWITCHED TELECOMMUNICATIONS NETWORKS.", TELETRAFFIC AND DATATRAFFIC IN A PERIOD OF CHANGE. COPENHAGEN, JUNE 19 - 26, 1991., AMSTERDAM, NORTH HOLLAND., NL, vol. CONGRESS 13, 19 June 1991 (1991-06-19) - 26 June 1991 (1991-06-26), NL, pages 127 - 132., XP000303019 *
PASSERON A.: "NETWORK SUPERVISION AND MANAGEMENT.", COMMUTATION ET TRANSMISSION., SOTELEC. PARIS., FR, vol. 13., no. SPECIAL., 1 January 1991 (1991-01-01), FR, pages 45 - 52., XP000241934, ISSN: 0242-1283 *
STACH J. F.: "GRAPH ANALYSIS AND RULE BASED PARADIGMS FOR THE IDENTIFICATION CONTAINMENT AND CLEARING OF SWITCH CONGESTION IN NON-HIERARCHICAL CIRCUIT SWITCHED NETWORKS.", PROCEEDINGS OF THE NATIONAL COMMUNICATIONS FORUM., NATIONAL ENGINEERING CONSORTIUM INC. OAK BROOK, ILLINOIS., US, vol. 43., no. 01., 2 October 1989 (1989-10-02), US, pages 474 - 481., XP000253912 *
TURNER P. M. D., KEY P. B.: "A NEW CALL GAPPING ALGORITHM FOR NETWORK TRAFFIC MANAGEMENT.", TELETRAFFIC AND DATATRAFFIC IN A PERIOD OF CHANGE. COPENHAGEN, JUNE 19 - 26, 1991., AMSTERDAM, NORTH HOLLAND., NL, vol. CONGRESS 13, 19 June 1991 (1991-06-19), NL, pages 121 - 126., XP000303018 *
WOLF R. B.: "ADVANCED TECHNIQUES FOR MANAGING TELECOMMUNICATIONS NETWORKS.", IEEE COMMUNICATIONS MAGAZINE., IEEE SERVICE CENTER, PISCATAWAY., US, vol. 28., no. 10., 1 October 1990 (1990-10-01), US, pages 76 - 81., XP000165758, ISSN: 0163-6804, DOI: 10.1109/35.60370 *
XUAN HUY PHAM.: "CONTROL LOOP FOR TRAFFIC MANAGEMENT OF NETWORK UNDER FOCUSSED OVERLOADS.", TELETRAFFIC AND DATATRAFFIC IN A PERIOD OF CHANGE. COPENHAGEN, JUNE 19 - 26, 1991., AMSTERDAM, NORTH HOLLAND., NL, vol. CONGRESS 13, 19 June 1991 (1991-06-19) - 26 June 1991 (1991-06-26), NL, pages 315 - 322., XP000303047 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5832064A (en) * 1996-05-30 1998-11-03 Electronics And Telecomunications Research Institute Mass calling processing method for televoting service
EP4404547A1 (fr) * 2023-01-17 2024-07-24 AVOXI, Inc. Surveillance proactive de numéro de téléphone sur la base d'un rapport de crise d'épilepsie de réponse

Also Published As

Publication number Publication date
JPH08500219A (ja) 1996-01-09
CA2135633C (fr) 1998-07-14
CA2135633A1 (fr) 1993-11-25
EP0640269A1 (fr) 1995-03-01
SG52408A1 (en) 1998-09-28

Similar Documents

Publication Publication Date Title
US5295183A (en) Congestion control system for telecommunications
US5799317A (en) Data management system for a telecommunications signaling system 7(SS#7)
CA2232331C (fr) Methode de repartition dynamique d'appels entre systemes a distributeurs d'appels automatiques
EP0606353B1 (fr) Gestion des encombrements dans des reseaux de telecommunication
CA1253241A (fr) Service telephonique pour distributeurs d'appels automatiques
US5583928A (en) Detecting local exchange failure and resultant control of a communications network
Haenschke et al. Network management and congestion in the US telecommunications network
US5509063A (en) Method of controlling a telecommunications network using call gapping
WO2002013497A1 (fr) Systeme de telecommunication
EP0726018A1 (fr) Systeme de gestion du trafic dans un reseau de telecommunications
CA2159505C (fr) Methode de controle pour reseau de telecommunication
EP0640269A1 (fr) Procede de regulation du trafic dans un reseau de telecommunications
US6275572B1 (en) Congestion control method and system in an exchange
EP0622937A2 (fr) Procédé d'évaluation rapide du dommage à une bande extérieur
US20040001577A1 (en) 10206963Apparatus and method for controlling telephone communications during intervals of high call traffic volume
WO1994000958A1 (fr) Procede de regulation de trafic dans un reseau de communication
CA2138278C (fr) Methode de controle du trafic dans un reseau de communication
AU7780298A (en) Overload prevention in a service control point (scp)
WO1995012291A1 (fr) Systeme de gestion du trafic dans un reseau de telecommunications
US5241579A (en) Status management method of a signalling service device in an electric switching system
Bodzik et al. Fossil1: a policy analysis model of the US energy transition
Mikami et al. Introduction of the International Network Management Center-Its activity and system
EP0726017B1 (fr) Systeme de gestion du trafic dans un reseau de telecommunications
SECTOR et al. IT5 Tq. 542
SECTOR et al. ITU-Tq. 542

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWE Wipo information: entry into national phase

Ref document number: 08173112

Country of ref document: US

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 2135633

Country of ref document: CA

WWE Wipo information: entry into national phase

Ref document number: 1993910183

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1993910183

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1993910183

Country of ref document: EP