LTE and EPC Roaming Testing Version 3.0 29 October 2020

GSM Association Non-confidential

Official Document IR.38 - LTE and EPC Roaming Testing

V3.0 Page 1 of 24

LTE and EPC Roaming Testing

Version 3.0

29 October 2020

This is a Non-binding Permanent Reference Document of the GSMA

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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.

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.

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The information contain herein is in full compliance with the GSM Association’s antitrust compliance policy.

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Table of Contents

1 Introduction 3

1.1 Scope of document 3

1.2 Test objectives 3

1.3 Definition of Terms 4

1.4 Document Cross-References 5

2 Requirements for Testing 6

2.1 Overview 6

2.2 Test Configuration 6

2.2.1 GTP-based LTE Roaming Configuration 6

2.2.2 CS Fallback / SMS over SGs Configuration 7

2.3 Prerequisites for the Network Entities 7

2.3.1 Prerequisites for LTE-only Testing 7

2.3.2 Prerequisites for CS Fallback / SMS over SGs Testing 10

2.3.3 Prerequisites for LTE+2G/3G Co-existence Testing 10

2.4 User Equipment 12

2.5 Test Equipment 13

2.5.1 Test equipment for LTE-only Testing 13

2.5.2 Test equipment for CS Fallback / SMS over SGs Testing 13

2.5.3 Test equipment for LTE+2G/3G Co-existence Testing 13

3 Test Cases 13

3.1 LTE-only Testing 13

3.1.1 LTE Speed test 13

The mean date rate is dependent on the local testing conditions. If the local

testing environment is different than the production one, then the

VPLMN should inform the HPLMN about the customer experience in the

latter case. 14

3.1.2 LTE Cancel Location 14

3.1.3 LTE Operator Determined Barring 15

3.2 CS Fallback / SMS over SGs Testing 16

3.2.1 CS Fallback Mobile Originating Voice Calls 16

3.2.2 CS Fallback Mobile Terminating Voice Calls 17

3.2.3 SMS over SGs (Mobile Originated and Mobile Terminated) 17

3.3 LTE+2G/3G Co-existence Testing 18

3.3.1 Data Access from 2G/3G using PGW in HPLMN (a) over Gp Interface 18

4 Pre-Testing Data Exchange 21

4.1 General 21

4.2 Testing Contact Information 21

4.3 PLMN/IP-addressing, numbering and routing data 21

4.3.1 LTE-only testing 21

4.3.2 CS Fallback / SMS over SGs testing 21

4.3.3 LTE+2G/3G Co-existence testing 22

4.4 USIM associated data supplied by PLMN (a) 22

4.5 Inter-PLMN Connection Parameters 22

4.6 IP-Server Information 22

5 Test Cases Excel Sheet 23

Annex A Document Management 24

A.1 Document History 24

Other Information 24

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1 Introduction

1.1 Scope of document

This provides the specifications for the Networks Group (NG) end-to-end functional

capability tests for services over Long Term Evolution (LTE) such as LTE data, Circuit

Switch (CS) Fallback voice and Short Message Service (SMS) over SGs, related to a User

Equipment (UE), belonging to a Home Public Land Mobile Network (HPLMN) (a), roaming

within a visited PLMN (VPLMN) (b).

Whilst it is expected that roaming will be a bilateral activity between two PLMNs, please note

that this document is written in a unidirectional context. Hence roaming is taking place by a

UE (a) to VPLMN (b) only. There is no reference to a UE (b) visiting PLMN (a).

To complete IREG end-to-end functional capability tests for bilateral roaming, it is necessary

to perform the tests contained in this document twice: the second time the identities of PLMN

(a) and PLMN (b) are swapped.

GSMA Permanent Reference Document (PRD) IR.23 [1] defines the scope and purpose of

each stage of testing.

GSMA PRD IR.88 [5] defines the LTE roaming and LTE+2G/3G co-existence guidelines. For

the 3GPP Release to be supported in each network, it is recommended to follow the

guidelines in IR.88 [5].

This document does not cover:

 Voice and Short Message Service (SMS) over LTE using IMS (See IREG PRD

IR.25 [2])

 Transferred Account Procedure (TAP), billing applications and any inter-PLMN

financial statement; (see TADIG PRD TD.41 [6]). However the production of a

Toll Ticketing file, to use in the TADIG Stage 3 testing is included.

 Definition of operation and maintenance procedures such as contact points for

fault reporting and notification of planned works. (See IREG PRD IR.23 [1]).

 Proxy Mobile IP (PMIP) protocol for the S8 roaming interface. Only the GTP

protocol is used for this interface.

1.2 Test objectives

The fundamental objective of this testing is to confirm the capability of LTE data/CS

Fallback/SMS over SGs services that users will experience when roaming from their

HPLMN(a) to a VPLMN(b). Consequently the tests are restricted to top-level capability

testing. There is no provocative or inopportune behaviour testing: this type of testing forms

part of the Stage 1 testing (see IREG PRD IR.23 [1]).

The overall objective of these tests is to confirm that functionality and features, which are

already known to operate correctly within each separate PLMN, will also operate correctly for

Inter-PLMN roaming.

Not all possible services should be tested.

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In addition to the handling of the tests, the collection/comparison of charging information for

the generation of Charging Detailed Records (CDR) is described.

The specific objectives are to prove that procedures defined in Section 2.1 of this document

behave correctly.

Bilateral agreement between the HPLMN and VPLMN require these tests to be repeated in

the opposite direction.

In order to maximize the efficiency of testing, the test cases have been specified so as to

minimize the requirement for simultaneous joint activity by both PLMN (a) and PLMN (b).

This applies mainly to the administration of mobile subscriber data in the HSS.

Accordingly, the testing program comprises three distinct stages:

a) HPLMN(a) issues pre-programmed Universal Subscriber Identity Module (USIM)

and programmes Home Subscriber Server (HSS)

b) VPLMN(b) performs tests

c) VPLMN(b) and HPLMN(a) discuss results

1.3 Definition of Terms

Term

Description

APN

Access Point Name

BSS

Base Station Subsystem

CDR

Charging Detailed Record

CCITT

International Telegraph and Telephone Consultative Committee

Circuit Switched

CSFB

Circuit-Switched Fallback

DNS

Domain Name System

EPC

Evolved Packet Core

EPS

Evolved Packed System

FQDN

Fully Qualified Domain Name

FTP

File Transfer Protocol

GGSN

Gateway GPRS Support Node

GMSC

Gateway Mobile Services Switching Centre

GPRS

Generic Packet Radio Access

GTP

GPRS Tunnelling Protocol

HSS

Home Subscriber Server

HPLMN

Home PLMN

HTTP

Hypertext Transport Protocol

IMSI

International Mobile Subscriber Identifier

Internet Protocol

ISP

Internet Service Provider

LTE

Long Term Evolution

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MAP

Mobility Application Part

MME

Mobility Management Entity

MSC

Mobile Services Switching Centre

ODB

Operator Determined Barring

PCRF

Policy and Charging Rules Function

PDN

Packet Data Network

PDP

Packet Data Protocol

PLMN

Public Land Mobile Network

PGW

PDN Gateway

SCCP

Signalling Connection Control Part

SGSN

Serving GPRS Support Node

SGW

Serving Gateway

SMS

Short Message Service

SMSC

Short Message Service Centre

TCAP

Transaction Capabilities Application Part

TCP

Transmission Control Protocol

UDP

User Datagram Protocol

User Equipment

USIM

Universal Subscriber Identity Module

VMSC

Visited Mobile Services Switching Centre

VLR

Visitor Location Register

1.4 Document Cross-References

Ref

Document

Number

Title

GSMA PRD IR.23

Organisation of GSM International Roaming Tests

GSMA PRD IR.25

VoLTE Roaming Testing

GSMA PRD IR.35

End-to-End Functional Capability Test Specification for Inter-

PLMN GPRS Roaming

GSMA PRD IR.67

DNS/ENUM Guidelines for Service Providers

GSMA PRD IR.88

LTE and EPC Roaming Guidelines

GSMA PRD TD.41

Testing the Transferred Account Procedure (TAP)

3GPP TS 23.060

General Packet Radio Service (GPRS); Service description; Stage

3GPP TS 29.303

Domain Name System Procedures; Stage 3

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2 Requirements for Testing

2.1 Overview

The test cases are divided in three (3) groups:

1. LTE-only services for UE (a) roaming to VPLMN (b) confirms a correct behaviour by

testing the following procedures:

a) LTE speed test

b) LTE Cancel Location

c) LTE Operator Determined Barring

2. Circuit Switch CS Fallback / SMS over SGs between UE1 (a) and UE2 (a) roaming to

VPLMN (b) confirms a correct behaviour by testing the following procedures:

a) CS Fallback – mobile originating and terminating voice calls

b) Verify that the UE can successfully return to eUTRAN after the voice call ends

c) SMS over SGs – mobile originated and terminated SMS

3. 2G/3G data services (i.e. web browsing) for UE (a) roaming to VPLMN (b) confirms a

correct behaviour by testing the following procedures:

a) Packet Data Protocol (PDP) Context Activation using Gp or S4/S8

For the 2G/3G data service using S4/S8, the testing of S8 interface (using GTP) is assumed

to be covered in the "LTE-only" test cases (see the prerequisites in Section 2.3.3). Thus this

PRD does not provide specific test cases for GTP variant for the 2G/3G data service.

Each operator has to make sure that the Access Point Name (APN) resolution algorithms

are implemented correctly in their Serving GPRS Support Node (SGSN) and MME (Mobility

Management Entity) according to GSMA PRD IR.88 [5] and GSMA PRD IR.67 [4].

2.2 Test Configuration

2.2.1 GTP-based LTE Roaming Configuration

The test configuration for LTE Roaming using GPRS Tunnelling Protocol (GTP)-based S8

interface is specified below.

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PLMN(a)

Country (b)

Country (a)

= Monitor

RADIUS/DHCP-SERVER

LOCAL DNS

INTRANET/ISP

ROOT DNS

Diameter

Edge Agent

Intra PLMN

GPRS / IP

EXCHANGE

PGW

HPCRF

HSS

USIM(a)

PLMN(b)

RADIUS/DHCP-SERVER

INTRANET/ISP

LOCAL DNS

PGW

eNB

MME

Diameter

Edge Agent

SGW

SGSN

RNS

/BSS

GGSN

Intra PLMN

Figure 2.2.1-1: GTP based LTE Roaming Configuration

2.2.2 CS Fallback / SMS over SGs Configuration

The test configuration for CS Fallback and SMS over SGs is specified below.

HLR/HSS

GMSC

PLMN(a)

MME

VLR/

VMSC

eNB

RNS/

BSS

PSTN

PLMN(b)

UE1(a)

USIM(a)

UE2(a)

USIM(a)

Figure 2.2.3-1: CS Fallback / SMS over SGs Configuration

2.3 Prerequisites for the Network Entities

2.3.1 Prerequisites for LTE-only Testing

Towards a first introduction of LTE Roaming, the following prerequisites are assumed:

1. UE supports necessary LTE capabilities for roaming in VPLMN (b).

2. The HSS contains LTE subscription data and routing information (PDN type, PDN

address, APN, and VPLMN address allowed (only applicable when Local Breakout is

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used)). These subscription data is permanent data in the HSS and has to be inserted

for the tests.

The HSS is accessible from the MME via the S6a interface. For roaming UEs, the HSS is in

a different PLMN than the current MME. The MME is updated with new an Evolved Packed

System (EPS) subscription data along with the “Update Location Request” or the “Insert

Subscriber Data” procedures.

International Mobile Subscriber Identifier (IMSI) is the primary key to the Evolved Packed

System (EPS) subscription data stored in the HSS.

The relevant parameters for the IREG testing in the HSS must be configured according to

the following table:

Field

Description

IMSI

IMSI is the main reference key.

MSISDN

The basic Mobile Subscriber ISDN Number (MSISDN) of

the UE (Presence of MSISDN is optional).

MME Capabilities

Indicates the capabilities of the MME with respect to the

core functionality e.g. regional access restrictions.

ODB parameters

Indicates the status of the operator determined barring

Access Restriction

Indicates the access restriction subscription information.

EPS Subscribed Charging

Characteristics

The charging characteristics for the MS, e.g. normal,

prepaid, flat-rate, and/or hot billing subscription.

Trace Reference

Identifies a record or a collection of records for a

particular trace.

Trace Type

Indicates the type of trace, e.g. HSS trace, and/or MME/

Serving GW / PDN GW trace.

OMC Identity

Identifies the OMC that shall receive the trace record(s).

Subscribed-UE-AMBR

The Maximum Aggregated uplink and downlink MBRs to

be shared across all Non-GBR bearers according to the

subscription of the user.

APN-OI-Replacement

Indicates the domain name to replace the APN OI when

constructing the PDN GW FQDN upon which to perform

DNS queries. This replacement applies for all the APNs

in the subscriber's profile.

RFSP Index

An index to specific RRM configuration in the E-UTRAN

URRP-MME

UE Reachability Request Parameter indicating that UE

activity notification from MME has been requested by the

HSS.

Each subscription profile contains one or more PDN subscription contexts:

Context Identifier

Index of the PDN subscription context.

PDN Address

Indicates subscribed IP address(es).

PDN Type

Indicates the subscribed PDN Type (IPv4, IPv6, IPv4v6).

Access Point Name (APN)

A label according to DNS naming conventions

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describing the access point to the packet data network

(or a wildcard).

EPS subscribed QoS profile

The bearer level QoS parameter values for that APN's

default bearer (QCI and ARP).

Subscribed-APN-AMBR

The maximum aggregated uplink and downlink MBRs to

be shared across all Non-GBR bearers, established for

this APN.

EPS PDN Subscribed Charging

Characteristics

The charging characteristics of this PDN Subscribed

context for the MS, e.g. normal, prepaid, flat-rate, and/or

hot billing subscription. The charging characteristics are

associated with this APN.

VPLMN Address Allowed

Specifies whether for this APN the UE is allowed to use

the PDN GW in the domain of the HPLMN only, or

additionally the PDN GW in the domain of the VPLMN.

PDN GW identity

The identity of the PDN GW used for this APN. The PDN

GW identity may be either a Fully Qualified Domain

Name (FQDN) or an IP address. The PDN GW identity

refers to a specific PDN GW.

PDN GW Allocation type

Indicates whether the PDN GW is statically allocated or

dynamically selected by other nodes. A statically

allocated PDN GW is not changed during PDN GW

selection.

List of APN - PDN GW ID relations (for PDN subscription context with wildcard APN):

APN - P GW relation #n

The APN and the identity of the dynamically allocated

PDN GW of a PDN connection that is authorized by the

PDN subscription context with the wildcard APN. The

PDN GW identity may be either a Fully Qualified Domain

Name (FQDN) or an IP address. The PDN GW identity

refers to a specific PDN GW.

Table 1: HSS Configuration for LTE-only roaming

3. S8 interface is implemented in HPLMN(a) and VPLMN(b) and both HPLMN(a) and

VPLMN(b) are using the same protocol (e.g. GTP)

4. MME has access to Domain Name System (DNS) functionality.

5. VPMLN MME local policies are configured for the Quality of Service.

6. Configuration of the test environment for transparent or non-transparent access to

Intranet/ Internet Service Provider (ISP) (The key point for the access of an Intranet

or an ISP infrastructure is the APN-Network-Identifier). This is sent by the UE during

Initial Attach or is set by default by the HSS. The APN-Network Identifier defines to

which external network the PDN Gateway (PGW) is connected to. This means, in

detail, the interface of the PGW to an external network. This external interface at the

PGW is connected to the infrastructure providing Intranet functionality (e.g. local

Hypertext Transport Protocol-Server or HTTP-Server) or similar to a Serverfarm

providing ISP functionality (HTTP-Server, Proxy-Server or File Transfer Protocol-

Server (FTP-Server) with connection to the external Internet). This mechanism

provides the physical path to the Intranet/ISP-functionality. However each operator

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needs to guarantee that the APN-resolution algorithms are implemented correctly in

his MME accordingly.

7. Dynamic Internet Protocol (IP) Address allocation for access to Intranet/ISP.

2.3.2 Prerequisites for CS Fallback / SMS over SGs Testing

For CS Fallback / SMS over SGs testing, the following prerequisites are assumed:

1. IREG tests for legacy 2G/3G CS domain services have already been performed

between HPLMN (a) and VPLMN (b) according to PRD IR.23 [1].

2. IREG tests for LTE-only services have already been performed between HPLMN (a)

and VPLMN (b) as specified in this document.

3. UE supports necessary CS Fallback and SMS over SGs capabilities for roaming in

VPLMN (b).

4. SGs interface is implemented between MME and Mobile Switching Centre/ Visitor

Location Register (MSC/VLR) in VPLMN (b).

5. Prerequisites for LTE-only testing have been met according to Section 2.2.4.1.

2.3.3 Prerequisites for LTE+2G/3G Co-existence Testing

For LTE+2G/3G Co-existence testing, the following prerequisites are assumed:

1. IREG tests for legacy 2G/3G PS domain services have already been performed

between HPLMN (a) and VPLMN (b) according to PRD IR.23 [1].

2. IREG tests for LTE-only services have already been performed between HPLMN (a)

and VPLMN (b) as specified in this document.

3. LTE and GPRS UE supporting the network operation modes in VPLMN (b).

4. HSS contains EPS subscription data for LTE roaming. Prerequisites are same as

described in Section 2.2.4.1.

The HSS contains GPRS and EPS subscription data and routing information (e.g. PDP/PDN

type (S)) for 2G/3G roaming.

This subscription data is permanent data in the HSS and must be inserted for the tests. The

HSS is accessible from the SGSN via the Gr interface. For roaming UEs, the HSS is in a

different PLMN than the current SGSN. The SGSN is updated with new GPRS and EPS

subscription data with the “Insert Subscriber Data” procedure.

IMSI is the primary key to the GPRS subscription data stored in the HSS.

If Gn/Gp interface is used for 2G/3G roaming, the subscription information stored in

HSS/HLR for 2G/3G roaming is defined in "Prerequisites for GPRS only roaming" table as

specified in PRD IR.35 [3].

If S4/S8 interfaces are used for 2G/3G roaming, the relevant parameters “GPRS

Subscription Data” for the IREG testing in HSS must be configured according to the following

table:

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HSS GPRS Subscription Data:

Field

Description

IMSI

IMSI is the main reference key.

MSISDN

The basic MSISDN of the MS

Subscribed Charging

Characteristics

The charging characteristics for the MS e.g. normal, prepaid, flat-

rate, and /or hot billing subscription

Trace Reference

Identifies a record or a collection of records for a particular trace.

Trace Type

Indicates the type of trace, e.g. Mobile Services Switching Centre

(MSC/BSS) trace, HLR trace, and/or SGSN/GGSN/BSS trace.

OMC Identity

Identifies the OMC that shall receive the trace record(s)

SMS Parameters

SMS-related parameters, e.g. operator-determined barring

GPRS-CSI

Optional GPRS CAMEL Subscription information, see TS23.016

MG-CSI

Optional Mobility Management for GPRS CAMEL subscription

information, see TS23.016

APN-OI Replacement

Indicates the domain name to replace the APN-OI when

constructing the Gateway GPRS Support Node (GGSN) FQDN

upon which to perform a DNS resolution. This replacement applies

for all the APNs in the subscribers' profile.

ODB for PS parameters

Indicates the status of the operator determined barring for packet

oriented services.

Access Restriction

Indicates the access restriction subscription information (Note: the

access restriction applies to both packet and circuit oriented

services).

RFSP Index

An index to specific RRM configuration in the UTRAN/GERAN

Each IMSI contains zero or more of the following PDP context subscription

records:

PDP Context Identifier

Index of the PDP context

PDP Type

PDP type, e.g., PPP or IP (IPv4, IPv6, IPv4v6)

PDP Address

PDP address, e.g., and IP address. This field shall be empty if

dynamic addressing is allowed.

Access Point Name

A label according to DNS naming conventions describing the access

point to the external packet data network.

In case of “Wild Card APN” this field shall be filled with

QoS Profile Subscribed

The quality of service profile subscribed. QoS Profile Subscribed is

the default level if a particular QoS profile is not requested.

VPLMN Address Allowed

Specifies whether the MS is allowed to use the APN in the domain

of the HPLMN only, and additionally the APN in the domain of the

VPLMN.

PDP Context Charging

Characteristics

The charging characteristics of this PDP Bearer Context e.g.

normal, prepaid, flat-rate and/or hot billing

EPS subscribed QoS profile

The EPS bearer level QoS parameter values for that APN's default

bearer (QCI and ARP)

APN-AMBR

The maximum aggregated uplink and downlink MBR values to be

shared across all Non-GBR EPS bearers, which are established for

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this APN.

Table 2: Additional HSS Configuration for 2G/3G Roaming using S4/S8 interface

1. Towards GPRS no supplementary services are invoked.

2. The Gp-Interface or S8-Interface is implemented between HPLMN (a) and VPLMN

(b).

3. SGSN in VPLMN (b) has access to DNS functionality.

4. Configuration of the test environment for transparent or non-transparent access to

Intranet/ISP (The key point for the access of an Intranet or an ISP infrastructure is

the APN-Network-Identifier). This is sent by the handset during PDP-context

activation or is set by default by the SGSN. The APN-Network Identifier defines to

which external network the PGW is connected to. This means, in detail, the interface

of the PGW to an external network. This external interface at the PGW (a) is

connected to the infrastructure providing Intranet functionality (e.g. local HTTP-

Server) or similar to a Serverfarm providing ISP functionality (HTTP-Server, Proxy-

Server or FTP-Server with connection to the external Internet). This mechanism will

provide the physical path to the Intranet/ISP-functionality. However each operator

has to make sure that the APN-resolution algorithms are implemented correctly in his

SGSN according to 3GPP TS 23.060 [7] and Annex A of 3GPP TS 23.060 [7].

5. Dynamic IP Address allocation for access to Intranet/ISP.

2.3.4 Prerequisites for 5G NSA Testing

For 5G NSA testing, the following prerequisites are assumed:

1. VPLMN is supporting EN-DC (Evolved-Universal Terrestrial Radio Access-New

Radio Dual Connectivity):

MME is sending the Feature Bit 27 in the Features of Feature-List-ID 2 of the Feature List

AVP as request in ULA or answer in IDA messages

2. HPLMN is supporting EN-DC (Evolved-Universal Terrestrial Radio Access-New

Radio Dual Connectivity:

HSS is sending the Feature Bit 27 in the Features of Feature-List-ID 2 of the Feature List

AVP as answer in ULR or request in IDS messages

3. MS1(a) is not restricted to NR access and is LTE Attached in VPLMN and with a

default bearer

2.4 User Equipment

The UE described in this section is necessary for undertaking the test cases described in

this document. This applies to all groups specified in Section 2.1 of this document:

1. Two UEs supplied by VPLMN (b).

2. Two LTE compatible USIMs supplied by HPLMN (a).

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The supply of additional USIMs may be agreed by the HPLMN (a) and VPLMN (b),

typically for the purposes of:

a) Spare cards in case of failure

b) Allocation from different HSSs

3. It shall be possible to specify what types of UEs are supplied for testing between

operator agreement (HPLMN (a) and VPLMN (b)).

2.5 Test Equipment

2.5.1 Test equipment for LTE-only Testing

The availability of a SGi, S6a, S8 and DNS interface IP testing and monitoring equipment is

highly advisable.

It is also recommended to have sample files and applications for data transfer testing.

2.5.2 Test equipment for CS Fallback / SMS over SGs Testing

The availability of an International Telegraph and Telephone Consultative Committee

(CCITT) # 7 tester able to decode Signalling Connection Control Part (SCCP), Transaction

Capabilities Application Part (TCAP) and Mobile Application Part (MAP) is highly advisable,

but not strictly necessary for these tests. However it is essential for any analysis of test case

failures.

Clock capable of being used to allow testing personnel to record call start and chargeable

start (answer) time of calls to an accuracy of better than five seconds is required. If possible,

the clock shall be adjusted to be in alignment with the internal MSC clock which is used for

the Toll Ticketing function.

Stopwatch capable of measuring perceived chargeable duration of calls to an accuracy of

one second.

2.5.3 Test equipment for LTE+2G/3G Co-existence Testing

The availability of a CCITT # 7 tester able to decode SCCP, TCAP, and MAP (for Gr

interface) is highly advisable, but not strictly necessary for these tests. However it is

essential for any analysis of test case failures.

The availability of a SGi, Gn, Gp, S6a, S6d, S8, S4 and DNS interface IP testing and

monitoring equipment is highly advisable.

It is also recommended to have sample files and applications for data transfer testing.

3 Test Cases

3.1 LTE-only Testing

3.1.1 LTE Speed test

Preconditions

1. UE1 contains USIM of HPLMN(a).

2. Neither MSC/VLR nor MME record exists for MS.

3. HLR/HSS record contains basic service information.

4. HPLMN to supply a HTTP/FTP page and file (20MB as per LTE GRQ) to download

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Action

1. Power-up UE1 (a) and perform Combined Attach procedure on VPLMN (b)'s LTE

network.

2. Check MME and MSC/VLR record for the IMSI/MSISDN of UE1.

3. Start the HTTP/FTP transfer

4. Check HTTP/ FTP mean data rate

Information Flow

Note: The information flow for Combined Attach is not provided in this version of the

document.

Expected Result

1. Successful result if the following results are both achieved:

 MSC/VLR and MME record is identical to the pre-testing information supplied by

PLMN (a).

 the HTTP/FTP mean data rate is in line with the following values:

Threshold

QoS parameter (KPI)

Geo-distance < 4000 km

Geo-distance ≥ 4000 km

FTP download mean data rate (Mbit/s)

≥ 13.5

≥ 6

HTTP mean data rate (Mbit/s)

≥ 11

≥ 5

Table 3: HTT/FTP Data rate values

Comments

This test case confirms the operation of Update Location and Insert Subscriber Data

procedure using SGs interfaces. It checks the support of the relevant SGs-AP, MAP and

Diameter (S6a) operations, TCAP processes and SCCP addressing for both E.214 and

E.164 Global Titles, between the HLR/HSS (a) and Visited Mobile Services Switching Centre

(VMSC) (b). It also checks the LTE speed.

The mean date rate is dependent on the local testing conditions. If the local testing

environment is different than the production one, then the VPLMN should inform the HPLMN

about the customer experience in the latter case.

3.1.2 LTE Cancel Location

Preconditions

1. MME (b) in VPLMN (b) contains EPS subscription information of UE1 (a).

2. PDN connectivity for UE1 (a) is activated.

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Action

HPLMN (a) personnel deletes UE1 (a) EPS-subscription from HSS (a) either using HSS`s

Man-Machine Interface or via Administrative Data Centre (ADC) input to HSS (a).

Information Flow

The information flow for LTE Cancel Location procedure is described as follows:

eNodeB

MME

2. Detach Request

3. Delete Session Request

11. Delete Session Response

12. Detach Accept

1. Cancel Location

13. Cancel Location ACK

Serving GW

PDN GW

hPCRF

HSS

vPCRF

7. Gateway Control Session Termination

Procedure

9. PCEF-Initiated IP-CAN

Session Termination

Procedure

8. Proxy Binding Update

10. Proxy Binding Ack

When PMIP is used

5. PCEF-Initiated IP-CAN

Session Termination

Procedure

4. Delete Session Request

6. Delete Session Resonse

When GTP is used

Figure 3: LTE Cancel Location Procedure

Expected Result

Successful result if records in MME (b), Serving Gateway (SGW) (b), PGW (a) and hPCRF

(a) for UE1 (a) have been erased and PDN connectivity for UE1 (a) has been deactivated.

Comments

This test case confirms that the “Cancel Location” procedure between HSS (a) and MME (b)

and the subsequent “Detach initiated by the network" procedure has behaved correctly.

3.1.3 LTE Operator Determined Barring

Preconditions

UE1 (a) is attached to VPLMN (b) and has a PDN connectivity.

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Action

1. HPLMN (a) personnel activates Operator Determined Barring (ODB) for PDN

connectivity for UE1 (a) from HSS (a) either using HSS`s Man-Machine Interface or

via Administrative Data Centre (ADC) input to HSS (a).

2. Check MME (b) for records of UE1(a).

3. Try to make a LTE-attach from UE1 (a) and send attach request from UE1 (a).

Information Flow

The information flow for LTE ODB procedure is described as follows:

MME

HSS

3. Reject

1. Insert Subscriber Data

2. Attach Request

Figure 4: LTE Operator Determined Barring Procedure

Expected Result

Successful result if MME (b) record for UE1 (a) containing ODB information, attach request

is rejected and no PDN connectivity establishment is successful.

Comments

This test case confirms that the “Operator Determined Barring” procedure between HSS (a)

and MME (b) behaves correctly.

3.2 CS Fallback / SMS over SGs Testing

3.2.1 CS Fallback Mobile Originating Voice Calls

Preconditions

1. UE1 (a) is CS Fallback capable.

2. UE1 (a) is camping on LTE.

3. UE2 (a) has attached successfully in VPLMN (b).

Action

1. UE1 (a) establishes call to UE2 (a).

2. Call is answered.

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Information Flow

Note: The information flow for CS Fallback Mobile Originating Voice Calls is not provided in

this version of the document.

Expected Result

Test is successful if the following results are both achieved

 Call is established.

 The UE successfully returns to eUTRAN in 9 to 11 seconds after the voice call is

ended.

Comments

This test case confirms the Mobile Originated call procedures using CS Fallback for roamers.

It checks the support of originating call setup procedures using SGs interface. It also checks

that the UE can successfully return to eUTRAN after the voice call ends.

3.2.2 CS Fallback Mobile Terminating Voice Calls

Preconditions

1. UE1 (a) is CS Fallback capable.

2. UE1 (a) is camping on LTE.

3. UE2 (a) has attached successfully in VPLMN (b).

Action

1. UE2 (a) establishes call to UE1 (a).

2. Call answered.

Information Flow

Note: The information flow for CS Fallback Mobile Terminating Voice Calls is not provided in

this version of the document.

Expected Result

1. Successful result if call is established.

2. Successful result if the UE successfully returns to eUTRAN after the voice call ends

Comments

This test case confirms Mobile Terminated call procedures using CS Fallback for roamers. It

checks the support of terminating call setup procedures using SGs interface. It also checks

that the UE can successfully return to eUTRAN after the voice call ends.

3.2.3 SMS over SGs (Mobile Originated and Mobile Terminated)

Preconditions

1. SMS-MO/MT is provisioned in HLR subscription. UE1 (a) and UE2 (a) are registered

in VPLMN (b).

2. UE1 (a) and UE2 (a) are both SMS over SGs capable.

3. UE1 (a) and UE2 (a) are camping on LTE.

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Action

1. Switch on UE1 (a) and UE2 (a).

2. Use UE1 (a) to transmit a 160 character Short Message to UE2 (a) via Short

Message Service Centre (SMSC) in HPLMN (a).

3. Await delivery of Short Message to UE2 (a) on LTE.

4. Check contents of Short Message with those transmitted.

Information Flow

Note: The information flow for SMS over SGs is not provided in this version of the

document.

Expected Result

Successful result if Short Message is correctly delivered within two (2) minutes of switching

UE2 (a) on.

Comments

This test case confirms correct operation of SMS over SGs - Mobile Originated / Terminated

for roamers.

3.3 LTE+2G/3G Co-existence Testing

3.3.1 Data Access from 2G/3G using PGW in HPLMN (a) over Gp Interface

Preconditions

1. UE1 (a) is GPRS-Attached in VPLMN (b) and camping on 2G/3G (e.g. UE in

STANDBY or READY state for 2.5G). The UE1 (a)’s LTE capability may be disabled

manually to fulfil this precondition.

2. No valid PDP contexts/EPS Bearers are established in the UE1 (a).

3. PDP context/EPS Bearers subscription record(s) exists in HSS (a) where PDP

type(S) = PDP type(R).

4. One PDP/PDN context subscription record exists in HSS (a) where APN(S) =

APN(R).

5. VPLMN not allowed for selected PDP/EPS Bearer context subscription records.

6. Access Point Name (APN) resolution algorithms are implemented correctly in SGSN

and PGW according to GSMA PRD IR.88 [5] and GSMA PRD IR.67 [4].

Action

1. UE1 (a) performs “Activate PDP Context Request”. PDP type (R) is sent by UE1 (a).

2. A PDP Address is not sent by UE1 (a) and is not present in a PDP context

subscription record. (Dynamic address allocation).

3. APN (R) (Network-ID, no Operator-ID) is sent by UE1 (a).

4. Pre-defined file is requested/transferred from External Network (Network-ID) to UE1

(a) by accessing HTTP-server over WEB-browsing.

5. UE1 (a) performs “Deactivate PDP Context Request”.

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Information Flow

The information flow for the procedures to support data access from 2G/3G using PGW in

HPLMN (a) over Gp interface is described as follows:

SGSN

VGGSN

APN:Intranet/ISP.mnc123.mcc456.gprs

mnc123.mcc456.gprs (VPLMN)

DNS (as per 3GPP TS 29.303)

Internet/ISP.apn.epc.mnc123.mcc888.3gppnetwork.org (HPLMN)

HPGW

APN: Internet/ISP.apn.epc.mnc123.mcc888.3gppnetwork.org

HSS

VPLMN

HP LMN

APN:Intranet/ISP

VPLMN add. not allowed

DNS (including S-NAPTR procedure) success

Figure 5: Data access from 2G/3G using PGW in HPLMN (a) over Gp interface

SGSN

VGGSN

APN:Intranet/ISP.mnc123.mcc456.gprs

mnc123.mcc456.gprs (VPLMN)

DNS (as per 3GPP TS 29.303)

Internet/ISP.apn.epc.mnc123.mcc888.3gppnetwork.org (HPLMN)

HPGW

APN: Internet/ISP.apn.epc.mnc123.mcc888.3gppnetwork.org

HSS

VPLMN

HPLMN

APN:Intranet/ISP

VPLMN add. not allowed

DNS (including S-NAPTR procedure) success

SGW

DNS

(as per 3GPP TS 29.303)

to select SGW

Figure 6: Data access from 2G/3G using PGW in HPLMN (a) over S8 interface

Expected Result

1. SGSN (b) receives APN (R) sent by UE1 (a).

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2. SGSN (b) selects PDP context subscription record (APN(S), APN(S) = (APN(R)) and

sets selection mode parameter to “subscribed”.

3. SGSN interrogates DNS-Functionality using procedures defined in 3GPP TS29.303

[8] with selected APN with appended HPLMN APN-Operator-ID.

4. Selected APN is translated to a PGW-Address in the HPLMN (a).

5. SGSN (b) returns an “Activate PDP Context Accept” message to the UE1 (a)

including PDP type and PDP address.

6. Valid PDP contexts are established in the UE1 (a).

7. Connection to Network specified by APN (Network-ID) is established.

8. Pre-defined file is successfully transferred at an agreed quality (data rate) with no

errors after using HTTP-Service.

9. EPS Bearer Context is deactivated, UE1 (a) performs "Deactivate PDP Context

Request".

Comments

This test case confirms PDP context activation/deactivation towards a home PGW (a) over

Gp interface with:

1. APN (R) is not empty, (Network-ID, no Operator-ID).

2. Setting of APN (Operator-ID) by subscription for HPLMN (a) = (APN(S)).

3. Setting up IP-tunnel connections (GTP, IP, User Datagram Protocol / Transmission

Control Protocol (UDP/TCP).

4. Root address lookup and dynamic address allocation.

If the PDP context activation procedure fails or if the SGSN returns an “Activate PDP

Context Reject” (Cause, PDP Configuration Options) message, then the user may attempt

another activation to the same APN up to a maximum number of attempts.

3.4 4G+5G NSA Testing

Preconditions

1. UE1 (a) is camping on LTE.

Action

1. Perform a speed test and record the results

2. MS1(a) moves under 5G coverage

3. Perform another speed test and record the new results

Expected Result

1. Additional bearer with 5G NR as Secondary RAT is activated

2. Speedtest rates are clearly higher than those measured from test 3.1.1

3. Captured trace in S1 shows gNodeB usage and validates NR usage

Comments

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This test case confirms the usage of NR as Secondary RAT with a 5G capable handset.

4 Pre-Testing Data Exchange

4.1 General

It is necessary for the two PLMNs to have exchanged the pre-testing data defined in the

following sections prior to the commencement of testing.

4.2 Testing Contact Information

The following test co-ordination contact information should be exchanged by both PLMNs:

1. Names

2. Telephone numbers

3. Fax numbers

4. Email address

4.3 PLMN/IP-addressing, numbering and routing data

4.3.1 LTE-only testing

For LTE-only testing is performed, the following information should be exchanged between

both PLMNs:

1. MME IP addresses used

2. SGW IP addresses used

3. PGW IP addresses used

4. Diameter Edge Agent IP addresses and FQDNs used

5. HSS IP addresses used

6. PDN subscription context

7. APNs

8. DNS IP-Addresses

9. HTTP/FTP page and 20MB file name

4.3.2 CS Fallback / SMS over SGs testing

If CS Fallback / SMS over SGs testing is performed, the confirmation of the PLMN

addressing numbering and routing data as referenced in PRD IR.23 [1] is regarded as

advisable. Such information includes:

1. E212-E214 translation

2. MSC/VLR and HLR E.164 addresses

3. MSRN number ranges

4. International Signalling Point Codes (if applicable)

5. SMS Service Centre E.164 address

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4.3.3 LTE+2G/3G Co-existence testing

If LTE+2G/3G Co-existence testing is performed, the following information should be

exchanged between both PLMNs:

1. E212-E214 translation

2. E164 Number range

3. International Gateway Signalling Point Codes

4. SMS Service Centre E164 address

5. SGSN-/PGW-IP addresses used

6. SGSN Global Title Address used

7. PDP Context / EPS Bearer profiles

8. APNs

9. DNS IP-Addresses

4.4 USIM associated data supplied by PLMN (a)

The following information as stored in the USIM and/or HSS is required individually for each

of the USIMs.

1. PIN, PUK/(SUPER PIN).

2. IMSI

3. MSISDN

4. Basic Service Subscription Information

5. Subscriber data concerning PDN connectivity

6. Access point names

In order to perform the tests, following USIM-card profile is required:

1. APN Name: “This should contain one HPLMNs APN” or “ * ” (wild card)

2. VPLMN allowed = no

4.5 Inter-PLMN Connection Parameters

In order to establish Inter-PLMN connectivity it is necessary to exchange information such

as:

1. Link transport, capacity and routing parameter

2. Link carrier and topology

3. Gp/S8 interface information

4. Security related information if necessary towards interconnection

5. LTE+2G/3G Co-existence scenarios being supported (see IR.88 [5] for the details)

4.6 IP-Server Information

The following information is required to provide IP-connectivity testing:

1. IP address of HPLMN (a) server (HTTP-, DNS-, PROXY-server), accessed via PGW

(a)

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5 Test Cases Excel Sheet

IR.38 V3.xlsm

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Annex A Document Management

A.1 Document History

Version

Date

Brief Description of Change

Approval

Authority

Editor /

Company

0.1-0.3

Initial drafts for discussion

Networks

Group

PSMC

Itsuma Tanaka,

NTT DOCOMO

0.4

24 August

2013

Version for approval

Networks

Group

PSMC

Itsuma Tanaka,

NTT DOCOMO

1.0

03 April 2014

CR for approval

Networks

Group

Itsuma Tanaka

NTT DOCOMO

2.0

07 November

2016

CR1001 PMIP removal

CR1002 Simplification Testing

and adding Speed Test

Networks

Group/PSMC

Jignesh Patel

Verizon

3.0

27 October

2020

CR1003 5G NSA Test Case

Jignesh Patel

Verizon

Other Information

Type

Description

Document Owner

NG PACKET

Editor / Company

Jignesh Patel, Verizon

It is our intention to provide a quality product for your use. If you find any errors or omissions,

please contact us with your comments. You may notify us at prd@gsma.com

Your comments or suggestions & questions are always welcome.