SGA-7N

The Sga-7N SS7 Network Monitoring system

Table of contents

• Introduction

• System Overview

  • System topology

  • Hardware components

    • Status of LED's on the Sga cards

  • Software components

    • Monitor units

    • The Server

      • The Signaling Link database

    • The Clients

    • The IN KPI subsystem

    • The SCCP (BSSAP) CDR subsystem

      • IMSI - MSISDN collection for SCCP records

    • The SGsAP CDR subsystem

    • The S1AP CDR subsystem

    • The GTP CDR subsystem

    • The Diameter S6/S13 CDR subsystem

    • The Diameter Cx CDR subsystem

    • The Universal Traffic Information Provider and BigData/EMC cell data loader system (Sga-UTI)

    • ISUP Based Fraud Detection (IBFD) subsystem

• Summary

Goals

• An ideal tool for locating faults and frauds in mobile and fixed networks of any size.
• Highly scalable traffic mass measurement system for developing and maintaining telephone networks
• Provide up-to-date information about traffic carried and the state of network links
• Essential information for debugging malfunctions
• Real-time tracing of fraudulent calls
• Pinpointing network bottlenecks

Operating principles

• The highly scalable system consists of one or more monitors, an Sga-7N server and the required software applications.
• It uses reliable, cost-effective industrial personal computers and modular application programs.
• The non-intrusive probes are connected to E1/T1 lines using Sga47 interface cards.
• SGA-7N system monitors SS7 signaling links directly without using the operator’s system resources.
• All signaling information is captured bit-by-bit for on-line and off-line analysis, including message statistics, call data records and real time call tracing.

Main features

• Non-intrusive 7/24 monitoring and capturing E1/T1 data streams
• Comprehensive message statistics: simple and complex statistics
• Supported protocols:
  • SS7 (MTP2-3, ISUP, SCCP, TCAP, MAP1-3, BSSAP, INAP, SMS, USSD)
  • HSL
  • DSS1
• Historical Call Data Records (CDR)
• Real time call tracing based on IMSI, MSISDN, O/DTID, S/DLR, ISUP, SCCP, MAP, BSSAP
• Detailed protocol decoding, filtering
• System wide alarm handling
• Centralized remote administration

Statistics

Low-level statistics

• Based on ITU recomendations
• Per signaling link
• General: LSSU, MSU, NACK, CRC, COO, CBD, stb. (Q.752/1, Q.752/3, Q.752/5, Q.752/9, Q.752/11)
• Local TCAP utilization statistics
  • counter-type (Q.752/13)
  • “1+delta”-type (Q.752/14)
• MAP statistics
  • general, MSC (GSM12-04/3.*)
  • related to the HLR (GSM12-04/4.*)
  • related to the VLR (GSM12-04/5.*)
  • related to the EIR (GSM12-04/6.*)
  • related to the SMS IWMSC/GMSC (GSM12-04/7.*)
  • related to messages USSD (GSM 09.02)
• BSSAP statistics
  • general (GSM12-04/3.*)
  • additional

Complex statistics

• Roaming call success (ProvideRoamingNumber)
  • Assembling: MAP/ProvideRoamingNumber_Inv(IMSI) and MAP/ProvideRoamingNumber_Res(RoamNum) and ISUP/IAM(CaPN=RoamNum), based on TIDs and RoamNum
  • Result: success of ProvideRoamingNumber operation on a per-IMSIprefix basis (IMSIPrefix, NI/OPC, number of PRN/noPRNI/noPRNR/noIAM/NumA)
• BSSAP Location Update success
  • cell-, more exactly “area”-changing
  • Assembling: BSSAP/DT1/LocUpd_Request and Accept/Reject
  • Result: success of area changing (Old MCC/MNC/LAC, new MCC/MNC/LAC/CI, OK, RejectCauase)

Call Data Records (CDR)

• Storage in binary datafiles
• Contains:
  • NI, DPC, OPC, CIC
  • IAM-, ACM-, CON-, REL-, RLC-TimeStamp
  • SUS-, RES-TimeStamps[.]
  • RelCause
  • TraMR
  • UseSI
  • NoA + CagPN, + TraNS, + CadPN, + OriCN, + RedGN
  • SignalingLink IDs

Bit level data access

• Signaling link selection
• Filtering
• Real time, or
• ... backward, tipically for 3-4 weeks (depends on disk capacity and traffic)
• Bit-by-bit

Decoding

• On-the-fly
  • Message processing inside the monitor machine
• Off-line
  • Messages captured from the monitors
  • Protocols:
    • ISUP
    • SCCP
    • BSSAP, BSSMAP, TCAP, MAP, INAP
    • SNM, SLT, IWUP stb.
    • DSS1

Call Trace

• Real time or off-line call tracing based on
  • MAP: IMSI or MSISDN
  • SCCP/TCAP: DTID/OTID or SLR/DLR
  • Simple: hexadecimal or Inverse BCD
  • BSSAP: subscriber's data (MSISDN, IMSI, TMSI, IMEI) or cell information (MSS/MNC/LAC/CI)
  • ISUP: MSISDN (only for ISUP/IAM or for every call related messages)
  • Roaming: IMSI for MAP/ProvideRoamingNumber_Inv and the corresponding MAP/PRN_Res and ISUP/IAM

Limits

• “SGA” 2Mbps interface cards
  • at most 31 signalink link / PCM
  • at most 2 bidirectional PCM / card
• “SGA” Monitor machines
  • at most 128 signaling link

Miscellaneous functions

• Timestamp accuracy is millisecond
  • Based on Network Time Protocol (NTP)
• Access control for clients
• Remote maintenance
  • Checking monitors and the server by a web-browser
  • Remote restart from Server with timing
• Fault tolerance for IP network degrading (KeepAlive)
• Statistics
  • “human readable” text files
  • automatically processable (PMS)
• Alarms
  • SNMP Traps
  • Sendable towards NOC/NMC/...
  • Convertable into SMS
• Logging
  • adjustable detail levels from ‘Off’ to ‘Debug’

What’s in the box?

• We provide:
  • SS7 monitors
    • telecom hardware + firmware, IT hardware + operating system, Sga-7N software
  • server complex
    • IT hardware + operating system, Sga-7N software
  • cables
  • support

Operating conditions

• Followings should be provided by the GSM network operator:
  • monitoring points to all international SS7 links
  • optionally SNMP access to NOC
  • reliable and safe IP network connection points
  • 230 Volts AC power points
  • local system administrator(s)

Contact

• e-mail: pvarga@tmit.bme.hu
• telephone: +36-1-4538080
• fax: +36-1-4538081
• mobile-phone: +36-30-7484575