DOCSLIB.ORG

2.5G/3G Core Network Testing with G35: the Foundation of Packet Switched Connectivity and Reliable IMS Services

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
2.5G/3G Core Network Testing with G35: the Foundation of Packet Switched Connectivity and Reliable IMS Services 2.5G/3G Core Network Testing with G35: The Foundation of Packet Switched Connectivity and Reliable IMS Services Abstract With the advent of broadband mobile networks like UMTS This whitepaper introduces some of the key procedures and service platforms like IMS, the interaction between needed to establish sessions in the packet-switched them both is leading to entirely new test challenges. 2.5G/3G core network, as well as at the service layer. Ensuring superior end-user Quality of Experience (QoE) is In this document, we will use IMS sessions as specific adequately supported by the underlying UMTS core and example. Related test challenges and how they can be access network infrastructure is just one of these new test addressed by using Tektronix’ G35 protocol test platform challenges being faced by Network Equipment are then highlighted. Finally, the impact of new services Manufacturers and service providers alike. such as Push-to-Talk over Cellular (PoC) and Multimedia Broadcast and Multicast Services (MBMS) on the 2.5G/3G core network infrastructure are explained. White Paper I www.tektronix.com/G35 White Paper | 2.5G / 3G Core Network Testing with G35 Introduction The adoption of recently standardized UMTS R5 and R6 features like HSDPA and HSUPA is transforming mobile networks into real broadband communication systems. Declining voice revenues require carriers to seek out alternative sources of revenues by developing new services for their customers. The advent of IEEE 802.16e, commonly known as “Mobile WiMAX”, as alternative mobile broadband technology will reinforce this trend. With this new technology, competing service providers appear on the horizon, thereby enabling more and more end users to adopt and incorporate IP-based services into their daily lives. IMS and other Packet Data platforms give service providers the ability to deploy multiple services with higher QoE at reduced overall cost. Applications as diverse as Ringtone Downloads, Text Messaging, E-Mail, Picture Messaging and Information Services have shown to be equally popular. Migrating these type of services towards a common platform in order to optimize Operating Expenses related costs will be a strong driver for mobile (and fixed) operators to adopt IMS-based systems. White Paper I www.tektronix.com/G35 2 White Paper | 2.5G / 3G Core Network Testing with G35 Primary and Secondary PDP Context The one thing all these different applications have in common After sending the Activate PDP Context Request, a timer is that a certain Access Point is needed for their availability. will be started in the MS while waiting for the Activate PDP Access Points are IP routers that provide the connection Context Accept or Reject message. between the Mobile Station (MS) and the selected application. The MS must know the Access Point Name The SGSN validates the Activate PDP Context Request. (APN) in order to contact the desired Access Point via the The SGSN rejects the PDP context activation request if no GPRS subsystem. This is done through a PDP context GGSN address can be derived, if the APN cannot be activation procedure as depicted in Figure 1. resolved or if the SGSN has determined that the Activate PDP Context Request is not valid. The MS sends an Activate PDP Context Request message that consists of PDP Type, PDP Address, Access Point If the PDP context activation procedure is successful, a Name, Quality of Service (QoS) Requested and Protocol user plane tunnel between the MS and an external Packet Configuration Options to the SGSN. The SGSN uses the Data Network (PDP) will be established. It is important to APN, which has the format of a ‘Fully Qualified Domain note that this is a user plane tunnel from GPRS perspective Name’, to select a reference point (the GGSN) to the external only; from the viewpoint of the external PDN, it would be network. The APN is a logical name referring to the external possible to also carry control plane information such as Packet Data Network (PDN) that the subscriber wishes to SIP messages. connect to. The Domain Name Server function resolves the logical APN name to an IP address. This function is As stated above, the Access Point is the first contact point standard Internet functionality according to RFC 1034 [1]. for the external service platform. Examples of such services As a result, the SGSN finds a GGSN that is connected to platforms are: the desired external network. In the next step, the SGSN I Short Message Service Center (SMSC) initiates the Create PDP Context Procedure to this GGSN. I Multimedia Messaging Service Center (MMSC) I QoS Requested indicates the desired QoS profile. Protocol Wireless Application Protocol (WAP) I Configuration Options may be used to request optional IP Multimedia Subsystem (IMS) I PDP parameters from the GGSN. Those Protocol Internet Configuration Options are then sent transparently through the SGSN. Figure 1. PDP Context Activation Procedure (MS initiated) White Paper I www.tektronix.com/G35 3 White Paper | 2.5G / 3G Core Network Testing with G35 One GGSN may offer different services that can be The QoS of any active primary or secondary PDP context accessed through different APNs. From the viewpoint of can be modified by the MS or network using the PDP the external PDN, the usage of primary and secondary PDP Context Modification procedure [2]. Figure 3 depicts the contexts must be distinguished (see Figure 2). A primary negotiated QoS parameters simulated by the G35 protocol PDP context will always be established for the first tester. For detailed information concerning QoS parameters connection between an MS and a specific APN. Up to 10 used in UMTS networks, refer to [3; chapter 6.4.3: “UMTS secondary PDP contexts may then be established if further Bearer Service Attributes”]. connections with the same APN are needed. Usually, every IMS media stream will be routed independently over a The maximum number of supported PDP contexts depends separate tunnel. This is necessary because the GPRS on the MS’s capabilities. Typical test mobiles support up to charging function in Release 5 is not able to generate six PDP contexts. SGSN/GGSN nodes can support up to multiple charging records for one data stream. Additionally, eleven PDP contexts per MS. For thorough stress testing, different IMS user plane sessions may have different QoS the G35 simulates up to 6 million mobile subscribers requirements. whereas every simulated MS may have up to 11 PDP contexts activated. With a total capacity of more than 60 Thus, PDP contexts can be categorized as following: million simultaneous GPRS tunnels, the G35 can simulate mobility scenarios and subscriber load ranging from a small 1. Primary PDP contexts: They provide connections to rural area up to the largest metropolitan city. different APNs. The SGSN assigns a unique IP address to the MS for each primary PDP context. 2. Secondary PDP contexts: They provide connections to the same APN, but with different QoS. A secondary PDP context is always associated with one primary PDP context. Both IP addresses and Access Points are re-used from the primary PDP context. Figure 3. Quality of Service IE (Screenshot from G35 Protocol Simulator) Figure 2. PDP Context Types White Paper I www.tektronix.com/G35 4 White Paper | 2.5G / 3G Core Network Testing with G35 Traffic Flow Template (TFT) and Protocol Configuration Options (PCO) Since a PDP address (e.g. IP address) is common for the The size of the packet filter content field itself is variable primary and for all associated secondary PDP contexts, the and contains exactly one of the following filter types: questions arises as to how user plane content (SIP signaling, voice, video, etc.) can be mapped to the correct GPRS I IPv4 source address tunnel (see Figure 2). As the IP Address alone is not an I IPv6 source address adequate indicator, another information element needs to I Next header type be exchanged during the Secondary PDP Context Activation I Single destination port procedure, the Traffic Flow Template (TFT) [2; chapter I Destination port range 9.2.2.1.1]. The TFT is provided by the MS, stored in the I Single source port GGSN and is examined when downlink user plane data I Source port range needs to be delivered to the MS. The TFT can be modified I IPSec Security parameter index or deleted by using the MS-initiated PDP Context I Traffic Class / Type of Service Modification procedure. By means of the MS initiated PDP I Flow Label Context Modification procedure, a TFT may also be assigned to a primary PDP context [2; chapter 9.2.3.3]. More information about usage and structure of the TFT Information Element can be found in [2; chapter 15.3] and The TFT Information Element is an array of packet filters [4; chapter 10.5.6.12: “Traffic Flow Template”]. and is used by the GGSN to inject IP packets (SIP, RTP, MPEG, etc.) into the correct GPRS tunnel. Each packet The relationship between PDP contexts, TFTs and packet filter has a variable length and consists of the following filters is depicted in Figure 4. elements: I packet filter identifier I packet filter evaluation precedence I the length of packet filter content I the packet filter content itself The packet filter identifier is used to identify each packet filter inside the TFT array. The packet filter evaluation precedence specifies the precedence class among all packet filters associated with a given PDP address (IP address). Signaling may have higher precedence than user plane, and streaming services a higher precedence than background services. Figure 4. PDP contexts, TFTs and Packet Filters White Paper I www.tektronix.com/G35 5 White Paper | 2.5G / 3G Core Network Testing with G35 The Evaluation Precedence Index specifies the order in The structure of the PCO IE is defined in [4; chapter which packet filters are examined.
Load more

Recommended publications
  • User Manual + Apn Settings for All Wireless Carriers in Usa
    www.iDroidUSA.com USER MANUAL + APN SETTINGS FOR ALL WIRELESS CARRIERS IN USA **User Manual in Española, French, Dutch and German is available for Download on Website: www.iDroidUSA.com Facebook Page: www.Facebook.com/iDroidUSA Twitter: @iDroidUSA USA: (215) 589-7118 USA: (713) 574-4737 CANADA: (604) 449-0055 EUROPEAN UNION: +32 487 888 888 Support Email: [email protected] 1 Notice Reproduction or distribution of this manual in any form is prohibited without prior written consent from the Company. The Company retains the right to modify and improve on any product described within this handbook without prior notice. Regardless of the circumstances, the Company shall not assume any liability for any data loss or any other type of losses; or for any special event or accidental damage caused directly or indirectly to or by the device. The content of this manual is provided as is and does not offer any kind of warranties, express or implied, for the accuracy, reliability of the content including, but not limited to, the implied warranty of merchantability and practical guarantee for a particular purpose unless specified by applicable law. The Company reserves the power to amend or withdraw any clause or warranty, in full, at any time without prior notice in this manual. The pictures in this manual are for reference only; if any individual picture does not match with the product please refer to the product material provided within this handbook as a standard. Many network functions described in this manual are special services provided by individual Network Service Providers which are independent of the Company.
    [Show full text]
  • IR.33 GPRS Roaming Guidelines V7.0
    GSM Association Non-confidential Official Document IR.33 - GPRS Roaming Guidelines GPRS Roaming Guidelines Version 8.0 20 May 2015 This is a Non-binding Permanent Reference Document of the GSMA Security Classification: Non-confidential Access to and distribution of this document is restricted to the persons permitted by the security classification. This document is confidential to the Association and is subject to copyright protection. This document is to be used only for the purposes for which it has been supplied and information contained in it must not be disclosed or in any other way made available, in whole or in part, to persons other than those permitted under the security classification without the prior written approval of the Association. Copyright Notice Copyright © 2015 GSM Association Disclaimer The GSM Association (“Association”) makes no representation, warranty or undertaking (express or implied) with respect to and does not accept any responsibility for, and hereby disclaims liability for the accuracy or completeness or timeliness of the information contained in this document. The information contained in this document may be subject to change without prior notice. Antitrust Notice The information contain herein is in full compliance with the GSM Association’s antitrust compliance policy. V8.0 Page 1 of 32 GSM Association Non-confidential Official Document IR.33 - GPRS Roaming Guidelines Table of Contents Introduction 4 Overview 4 Scope 4 1 Architecture and Interfaces 4 1.1 1.1 Definition of Terms 5 1.1.11.2 Document Cross-References
    [Show full text]
  • Lecture #9 3G & 4G Mobile Systems E-716-A
    Integrated Technical Education Cluster Banna - At AlAmeeria ‎ © Ahmad El E-716-A Mobile Communications Systems Lecture #9 3G & 4G Mobile Systems Instructor: Dr. Ahmad El-Banna December 2014 1 Ok, let’s change ! change Ok, let’s 2 E-716-A, Lec#9 , Dec 2014 © Ahmad El-Banna Banna Agenda - Evolution from 2G to 3G © Ahmad El 3G Systems Objectives Alternative Interfaces UMTS , Lec#9 , Dec 2014 Dec Lec#9 , , A - 716 3.5G (HSPA) - E 4G (LTE) 3 Evolution from 2G Banna - 2G IS-95 GSM- IS-136 & PDC © Ahmad El GPRS IS-95B 2.5G HSCSD EDGE , Lec#9 , Dec 2014 Dec Lec#9 , , A - 716 - E Cdma2000-1xRTT W-CDMA 3G EDGE Cdma2000-1xEV,DV,DO 4 TD-SCDMA Cdma2000-3xRTT 3GPP2 3GPP Banna GSM to 3G - High Speed Circuit Switched Data Dedicate up to 4 timeslots for data connection ~ 50 kbps Good for real-time applications c.w. GPRS Inefficient -> ties up resources, even when nothing sent © Ahmad El Not as popular as GPRS (many skipping HSCSD) Enhanced Data Rates for Global Evolution GSM HSCSD Uses 8PSK modulation 9.6kbps (one timeslot) 3x improvement in data rate on short distances GSM Data Can fall back to GMSK for greater distances Also called CSD Combine with GPRS (EGPRS) ~ 384 kbps , Lec#9 , Dec 2014 Dec Lec#9 , , A Can also be combined with HSCSD - GSM GPRS 716 WCDMA - E General Packet Radio Services Data rates up to ~ 115 kbps EDGE Max: 8 timeslots used as any one time Packet switched; resources not tied up all the time 5 Contention based.
    [Show full text]
  • F5 and the Growing Role of GTP for Traffic Shaping, Network Slicing, Iot, and Security
    OVERVIEW F5 and the Growing Role of GTP for Traffic Shaping, Network Slicing, IoT, and Security For years, F5 BIG-IP solutions have managed GPRS Tunneling Protocol (GTP) traffic. Now, in part due to EU regulations, GTP traffic growth is much higher than ever before. International trends show that mobile data is increasing, as is the demand for smart and secure GTP traffic handling. In this document, we will explain GTP, where it is typically used, and where BIG-IP solutions provide significant value. What is GTP? GTP is a group of IP-based communication protocols used to carry General Packet Radio Service (GPRS) within GSM, UMTS, and LTE networks. In 3GPP architectures, GTP and Proxy Mobile IPv6-based interfaces are specified on various interface points. GTP in GPRS (2.5G and 3G) Networks GTP is a set of three separate protocols: GTP Control (GTP-C), GTP User (GTP-U), and GTP Prime (GTP’). GTP-C is used within the GPRS core network for signaling between gateway GPRS support nodes (GGSN) and serving GPRS support nodes (SGSN), as demonstrated by the Gn interface on the diagram below. GTP-C allows the SGSN to activate and deactivate a user’s session, adjust quality- of-service parameters, or update sessions when subscribers arrive from another SGSN. HLR MSC Gr Gs luPS Internet Gi Gn SGSN RNC UMTS Radio Network (RAN) GGSN Gb Corporate SGSN PCU GSM Radio Network Network (BSS) Figure 1: GTP in GPRS (2.5G and 3G networks). OVERVIEW | F5 and the Growing Role of GTP 2 GTP-U carries user data within the GPRS core network, and between the radio access network and core network.
    [Show full text]
  • ETSI TS 123 101 V8.0.0 (2009-01) Technical Specification
    ETSI TS 123 101 V8.0.0 (2009-01) Technical Specification Universal Mobile Telecommunications System (UMTS); LTE; General UMTS Architecture (3GPP TS 23.101 version 8.0.0 Release 8) 3GPP TS 23.101 version 8.0.0 Release 8 1 ETSI TS 123 101 V8.0.0 (2009-01) Reference RTS/TSGS-0223101v800 Keywords LTE, UMTS ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://portal.etsi.org/tb/status/status.asp If you find errors in the present document, please send your comment to one of the following services: http://portal.etsi.org/chaircor/ETSI_support.asp Copyright Notification No part may be reproduced except as authorized by written permission.
    [Show full text]
  • UMTS Core Network
    UMTS Core Network V. Mancuso, I. Tinnirello GSM/GPRS Network Architecture Radio access network GSM/GPRS core network BSS PSTN, ISDN PSTN, MSC GMSC BTS VLR MS BSC HLR PCU AuC SGSN EIR BTS IP Backbone GGSN database Internet V. Mancuso, I. Tinnirello 3GPP Rel.’99 Network Architecture Radio access network Core network (GSM/GPRS-based) UTRAN PSTN Iub RNC MSC GMSC Iu CS BS VLR UE HLR Uu Iur AuC Iub RNC SGSN Iu PS EIR BS Gn IP Backbone GGSN database Internet V. Mancuso, I. Tinnirello 3GPP RelRel.’99.’99 Network Architecture Radio access network 2G => 3G MS => UE UTRAN (User Equipment), often also called (user) terminal Iub RNC New air (radio) interface BS based on WCDMA access UE technology Uu Iur New RAN architecture Iub RNC (Iur interface is available for BS soft handover, BSC => RNC) V. Mancuso, I. Tinnirello 3GPP Rel.’99 Network Architecture Changes in the core Core network (GSM/GPRS-based) network: PSTN MSC is upgraded to 3G MSC GMSC Iu CS MSC VLR SGSN is upgraded to 3G HLR SGSN AuC SGSN GMSC and GGSN remain Iu PS EIR the same Gn GGSN AuC is upgraded (more IP Backbone security features in 3G) Internet V. Mancuso, I. Tinnirello 3GPP Rel.4 Network Architecture UTRAN Circuit Switched (CS) core network (UMTS Terrestrial Radio Access Network) MSC GMSC Server Server SGW SGW PSTN MGW MGW New option in Rel.4: GERAN (GSM and EDGE Radio Access Network) PS core as in Rel.’99 V. Mancuso, I. Tinnirello 3GPP Rel.4 Network Architecture MSC Server takes care Circuit Switched (CS) core of call control signalling network The user connections MSC GMSC are set up via MGW Server Server (Media GateWay) SGW SGW PSTN “Lower layer” protocol conversion in SGW MGW MGW (Signalling GateWay) RANAP / ISUP PS core as in Rel.’99 SS7 MTP IP Sigtran V.
    [Show full text]
  • UMTS Overview
    UMTS overview David Tipper Associate Professor Graduate Telecommunications and Networking Program University of Pittsburgh 2720 Slides 12 UMTS • ETSI proposed GSM/NA-TDMA /GPRS evolution under name Universal Mobile Telecom. Services (UMTS) • Most of 3G licenses in Europe required operator to deploy a UMTS system covering x% of population by a specific date y – Germany: 25% of population by 12/03, 50% by 12/05 –Norway: 80% of population by 12/04 – In most countries operators have asked for and received deployment delay due to dot.com bust and equipment delays • Estimate 2.5 Billion euros to deploy a 5000 base station UMTS system • According to UMTS Forum – More than 90 million UMTS users as of 10/06 on operating networks in more than 50 countries – Most deployments of UMTS in Europe (~40% of market) and Pacific Rim (~38% market) Telcom 2720 2 UMTS • UMTS is a complete system architecture – As in GSM emphasis on standardized interfaces • mix and match equipment from various vendors – Simple evolution from GPRS – allows one to reuse/upgrade some of the GPRS backhaul equipment – Backward compatible handsets and signaling to support intermode and intersystem handoffs • Intermode; TDD to FDD, FDD to TDD • Intersystem: UMTS to GSM or UMTS to GPRS – UMTS supports a variety of user data rates and both packet and circuit switched services – System composed of three main subsystems Telcom 2720 3 UMTS System Architecture Node B MSC/VLR GMSC PSTN RNC USIM Node B HLR ME Internet Node B RNC SGSN GGSN Node B UE UTRAN CN External Networks • UE (User Equipment) that interfaces with the user • UTRAN (UMTS Terrestrial Radio Access Network) handles all radio related functionality – WCDMA is radio interface standard here.
    [Show full text]
  • Security for the Core Network of Third Generation Mobile Systems
    Security for the core network of third generation mobile systems GUNTER HORN, DIRK KROSELBERG Siemens AG, Corporate Technology, D-81730 Muenchen, Germany STEFANPUTZ T-Mobil, P.O. Box 300463, D-53184 Bonn, Germany ROLAND SCHMITZ T-Nova Technology Centre, D-64307 Darmstadt, Germany Keywords: UMTS, MAP Security, Multimedia domain, SIP, IPSec, IKE, Key Management Abstract: This contribution gives a survey of the present standardisation activities by 3GPP (3'd Generation Partnership Project1) in the area of security for signalling in the core network of third generation mobile systems. We give an overview of the protocols that need to be secured, present the basic principles behind the overall security architecture and describe the key management and format of secured messages, as far as they have already been finalised. In particular, we address core network security aspects of the 3GPP multimedia domain. 1 3GPP was formed by regional standards organisations from Europe, Asia and North America to produce specifications for a third generation mobile system named UMTS which is designed to evolve from GSM core network. There is a competing effort known as 3GPP2 with partners from North America and Asia. The original version of this chapter was revised: The copyright line was incorrect. This has been corrected. The Erratum to this chapter is available at DOI: 10.1007/978-0-387-35413-2_36 R. Steinmetz et al. (eds.), Communications and Multimedia Security Issues of the New Century © IFIP International Federation for Information Processing 2001 298 1. THREATS TO CORE NETWORK SECURITY FOR MOBILE RADIO NETWORKS The core network of mobile radio systems is the part of the network which is independent of the radio interface technology of the mobile terminal.
    [Show full text]
  • Download Our Sim Card Userguide
    Before leaving, download the My DataSIM app with a Wi-Fi connection: Welcome! We are happy to have you as a new customer! Getting started Once arrived at your travel destination, detach the SIM card in the format corresponding to your device* and insert. Then take a few minutes to configure your device in 3 steps: Configure your APN settings (Access Point Name) as follows: Need more help? Find our videos on: APN = mobiledata / Username = mobiledata www.transatel-datasim.com/video-tutorials All other fields should be left empty For detailed help, please see the reverse side of this form. Activate data roaming and 4G connection in your settings. No worries, there won’t be any extra charges with the data roaming option ON. For detailed help, please see the reverse side of this form. Create your account to check your balance and recharge your SIM card. Using your Transatel DataSIM card’s 3G/4G connection: Open your My DataSIM app and fill in your information. *Make sure your device is not Or simply go to: https://tds-selfcare.com carrier-locked You can now start surfing the web! Checking your balance/recharging Once logged into your My DataSIM account, you can (free of charge): Check your credit Recharge for Buy a recurring and data allowance 100+ destinations bundle Help for configuration APN and data roaming are not situated in the same menus, depending on the device. Please follow the guide below: CONFIGURING APN SETTINGS ENABLING DATA ROAMING ENABLING 4G/LTE Settings More settings Settings More Mobile networks Settings More settings Mobile
    [Show full text]
  • TR 101 865 V1.1.1 (2001-07) Technical Report
    ETSI TR 101 865 V1.1.1 (2001-07) Technical Report Satellite Earth Stations and Systems (SES); Satellite component of UMTS/IMT-2000; General aspects and principles 2 ETSI TR 101 865 V1.1.1 (2001-07) Reference DTR/SES-00054 Keywords satellite, UMTS, IMT-2000, 3GPP ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.:+33492944200 Fax:+33493654716 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://www.etsi.org/tb/status/ If you find errors in the present document, send your comment to: [email protected] Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © European Telecommunications Standards Institute 2001. All rights reserved. ETSI 3 ETSI TR 101
    [Show full text]
  • Mobile Computing
    10/21/12 Mobile Computing CSE 40814/60814 Fall 2012 Public Switched Telephone Network - PSTN! Transit switch Transit Transit switch Long distance network switch Local Local switch switch Outgoing Incoming call call - Transfer mode: circuit switching! - All the network (except part of the access network) is digital! - Each voice channel is usually 64kb/s! 1 Basic Call! Calling terminal Network Called terminal Off-hook Resource allocation Dial tone Dialing Translation + routing Ring indication Alert signal Remove ring indication Off hook Bi-directional channel Conversation On hook On hook signal Billing 2 1 10/21/12 Cellular Network Basics •" Cellular network/telephony is a radio-based technology; radio waves are electromagneFc waves that antennas propagate •" Most signals are in the 850 MHz, 900 MHz, 1800 MHz, and 1900 MHz frequency bands Cell phones operate in this frequency range (note the logarithmic scale) Cellular Network •" Base staons transmit to and receive from mobiles at the assigned spectrum –" MulFple base staons use the same spectrum (spectral reuse) •" The service area of each base staon is called a cell •" Each mobile terminal is typically served by the ‘closest’ base staons –" Handoff when terminals move Architecture of Cellular Networks! Server (e.g., Home Location Register) External Mobile Network Station Base Mobile Station Switching Center Cellular Network 5 2 10/21/12 6 Registration! Nr: 079/4154678 Tune on the strongest signal 7 Service Request! 079/4154678 079/8132627 079/4154678 079/8132627 8 3 10/21/12 Paging Broadcast! 079/8132627? 079/8132627? 079/8132627? 079/8132627? Note: paging makes sense only over a small area 9 Response! 079/8132627 079/8132627 10 Channel Assignment! Channel Channel 47 Channel 47 68 Channel 68 11 4 10/21/12 Conversation! 12 Handoff (or Handover)! 13 Message Sequence Chart! Base Base Caller Switch Callee Station Station Periodic registration Periodic registration Service request Service request Page request Page request Paging broadcast Paging broadcast Paging response Paging response Assign Ch.
    [Show full text]
  • Testing the UMTS Iu Interface Testing the UMTS Iu Interface ▲ ▲ Application Note Application Note
    ▲ Application Note COMPUTING TELECOM Testing the UMTS Iu Interface VIDEO ▲ Protocol Testing in the 3G Wireless Network This application note describes protocol tests for the UMTS Iu interface between the Radio Network Controller (RNC) and the Core Network (CN). It is the first in a series of documents on third-generation (3G) wireless networks. Each note addresses one of the new network interfaces and provides guidelines for equipment designers, manufacturers, operators and maintenance personnel to meet the measurement challenges with testing solutions. Examples are given in this document for testing: • Messaging and procedures on the Radio Access Network (RANAP) • Mobile Radio Interface Layer 3 (CC/MM/GPRS MM/GPRS SM) • Traffic channel signaling (AAL2 layer3) • Tunneling (GTP-U). Due to space limitations, only brief descriptions are presented here. Complete detailed information needed to perform these and other tests can be found in the user handbooks for the K1297 and K1205 Protocol Testers and in other training materials. Please contact Tektronix sales support to obtain the most recent information. Testing the UMTS Iu Interface Testing the UMTS Iu Interface ▲ ▲ Application Note Application Note Table of Contents 1. Introduction – The Iu Interface and All traffic over the Iu interface uses the Asynchronous Transfer Mode (ATM) as Protocols 1. INTRODUCTION – THE Iu INTERFACE AND PROTOCOLS ..................................................................................................................................................3 the physical transport technology, regardless of the data source. As a result, all data will be segmented into 53-byte ATM-cells and transported 1.1. TRANSPORT PROTOCOLS FOR THE CONTROL PLANE ........................................................................................................................................3 asynchronously. This document describes test applications for the Iu interface as it was defined 1.2.
    [Show full text]