Discussion of 3G Interoperability test

Interoperability testing (IOT) is the technical basis for the formation of multiple vendor operating environments. Only through the interoperability testing of IU interface can the interconnection between wireless access network and core network of different manufacturers be ensured, and only the interoperability test of UU interface can be done to ensure interconnection between each mobile phone and wireless access system.

From the world has completed 3G equipment selection can be seen, there is a very obvious trend is that the same operators mostly choose 2~3 manufacturer's equipment to form their own 3G network, the formation of multi-vendor equipment operating environment. Therefore, interoperability testing between different vendors is particularly important for the 3G era. 3G System interoperability testing, coordinated by the Nv-iot Forum, has been in Europe for more than two years, and the world's leading communications equipment companies are involved in interoperability testing of different manufacturers ' equipment.

Interoperability testing has been placed in a very important strategic position, for this reason, the Ministry of Information industry has deliberately organized all participating in the Ministry of Information industry 3G technology test system manufacturers and mobile phone manufacturers of UU and IU Interface Interoperability test to verify the interoperability between the system and the mobile phone and system.

It is well known that the software versions of wireless systems and mobile phones require version upgrades to add new functionality over time, so interoperability testing is not a one-time solution to all problems (especially when both sides are adding new features), so interoperability testing is a long-term process.

First, Nv-iot Forum Introduction

NV (Network Vendor)-iot FORUM originated in the informal forum on GPRS interoperability testing established by some major GSM system manufacturers in March 2000. The February 2001 Nv-iot Forum was formally established, and the scope of interoperability testing was extended to 3G systems. Nv-iot Forum launched a member of Alcatel, Ericsson, Lucent, Motorola, Nokia, Nortel Network, Siemens, then the domestic Datang, Huawei, ZTE also participated in the Nv-iot forum, and become a full member of the Nv-iot forum.

The emergence of Nv-iot forum can effectively organize the whole industry to IoT the whole unified norms and processes, thereby improving the IoT efficiency and quality. Through successful IoT, operators can better understand the interoperability capabilities of device manufacturers, facilitate the integration of multi-vendor environments faster, thus helping operators to quickly shift their focus to verification of business capabilities. The more important significance of IoT is the promotion of open interfaces, which can help operators reduce initial network investment and reduce risk. At the same time, equipment manufacturers with core competitiveness of products can be put into the market faster, to seize the market opportunities.

But the special note is that Nv-iot forum is a relatively loose alliance, it is only for IOT specification, IOT Ordinary project operation flow, joint test plan, test report format or approximate content to stipulate, and provide to all members for reference, it does not have the right to restrict and arrange the IOT between the manufacturers. The IoT between the manufacturers is entirely based on the manufacturer's own situation and make their own choice. Therefore, IoT often become a powerful combination of 3G manufacturers or in some areas of the business development of an important tactical means. (Computer science)

Multi-vendor IoT are usually composed of the ordinary IoT and the IoT which have the operator's participation.

1. Stage One: Ordinary IoT

The test contents of the common IoT include:

Two common IoT between vendors based on the 3GPP public interface;

The main test is directly related to the interface function;

The parameters of integration and testing are determined by the manufacturers themselves;

On the basis of the agreement of the test manufacturer, any operator can refer to the common interoperability test results based on this configuration.

2. Basic flow of ordinary IoT

Figure 1 shows the basic process of common interoperability testing, which is now mostly based on the IoT process.

(1) standard for entering IoT test

The two sides signed NDA (Non-disclosure agreement);

The two parties exchange a SOC based on a specific interface (Statement of Compliance);

Complete table testing;

The two sides agreed to test the configuration and test project;

Both sides of the equipment to complete self-test;

There are test cell phones.

(2) Criteria for exiting IoT

All test items have been completed;

The joint test report shall be accepted after mutual audit;

The two sides worked out the next work plan together.

(3) Error Reporting

If a compatibility issue is found in the test, the Parties shall submit the question to the technical working Group for discussion, which is comprised of research and development, standards and testing experts from both sides;

If the solution is found, the whole IoT should be completed after the completion of the test;

If there is no agreement between the experts on the issue, then the differences may occur in the manufacturer's understanding of the ETSI/3GPP specifications, resulting in different product implementation, then two manufacturers should submit the issue to 3GPP corresponding working group for discussion.

(4) Final report and Medium test report

After each test phase is completed, the parties should prepare a joint report;

The report should contain the major milestones in the IoT (test plan, results achieved during the testing process);

The final report should contain the final status of the test project (Ok/nok), the changes that have occurred, and the plan of response to the NOK test item.

3. Phase II: IoT with operator involvement (mvi-local multi-vendor integration)

The test content of IoT with operator involvement includes:

Integration and verification based on the special requirements of operators;

The parameters of integration and testing are determined by operator;

The local MVI is carried out in the operator's field, coordinated by the operator and the manufacturer;

Mainly dedicated to the system End-to-end performance and application verification based on the common IoT;

The common IoT result is the basis of MVI.

Because this stage operator participates in IoT, so the organizational structure of the project is somewhat different from the ordinary IoT, because it means that at least three parties will work together to set up a project team to coordinate the entire test, the general project manager should be the customer, and the manufacturer's IoT project team should be the same as the normal IoT organizational structure.

Second, 3G Interoperability testing status

Figure 2 shows the scope of the 3g-network IoT, 3G IoT involves a lot of interfaces, but the most important interface has 2: UU and IU is Iu-cs and Iu-ps, so the Ministry of Information industry in the 3G technology test deliberately arranged between different manufacturers of UU and IU interface IoT.

The IoT of the 3g-network iu-interface mainly validates the following listed features:

Saal-nni, mtp3b, SCCP, Alcap;

The test of Ranap mainly verifies the functions of Rab finger matching, releasing IU, paging, Reset, common ID, etc.

Mobility Management testing includes location updates, paging, relocation (3g/3g, 3g/2g);

Call processing: MOC, MTC, emergency calls;

Group domain test: Attach, Detach, 384kbit/s data transmission;

Circuit-domain Data testing: 64KBIT/S data transmission based on videophone.

From 2001 onwards, many domestic and foreign manufacturers began based on multi-vendor Environment 3G Network IoT, testing mainly includes: Iu-cs, Iu-ps, Iur, Gr, Gp, Gn, C/D and other interfaces, from the functional perspective mainly includes: AMR voice call, circuit domain 64kbit/s, group domain 64 /128/384KBIT/S, some security features (authentication, integrity protection, encryption, etc.), concurrent Business Multi RAB (AMR call + PS data), 3G/2G switching, based on the Iur interface soft switching.

Operators both at home and abroad attach great importance to the network operating environment of multi-vendor equipment. In the MVI stage, the operators pay more attention to the verification of various applications and network quality in the environment of multi-vendor equipment, compared with the ordinary IoT stage, the manufacturers can only realize the interoperability of different equipment. So the MVI stage to the reliability of the manufacturer's equipment, the carrying capacity of the business, the system's wireless indicators have put forward higher requirements.

The prospect of 3G interoperability testing

Nv-iot Forum in the organization of coordination, compared with other 3G technology system, 3G IOT is the most perfect and is fully validated, which effectively guaranteed the 3G network successfully implemented commercially, for operators to introduce competition, the establishment of a multi-vendor network environment has laid a very good technical basis.

3G after several years of development, UU interface, IU interface IoT has been basically completed, domestic and foreign mainstream manufacturers and equipment interoperability between the existing problems, some domestic manufacturers are actively with foreign manufacturers to do more interface IoT (such as Iur, C/D, e/g, gn/gp/gr).

In the next period of time, IoT will focus on switching between 3g/2g systems, for 3G just spread out and 3G network coverage needs to 2G (GSM) switching to maintain business continuity and prepare. When the testing of all interfaces is complete, the main task of IoT is to validate the new features and new standard versions (such as 3GPP R4) as the manufacturer's software version is upgraded.

The technology realization and analysis of illegal VoIP detection

-China Telecom Group Chi Jingping

I. Illegal VOIP operation

VoIP Business is the international telecommunications operators of the dilemma of choice, for China Telecom operators are more so. The development of VoIP business has resulted in the slow growth of long-distance telephone service, and even the lower income of individual areas, especially the impact on international long-distance business.

Due to the flexibility and openness of IP network, the huge profit space brought by VoIP and the problem of national supervision, some unscrupulous personnel are carrying out the underground IP telephone, commonly known as "information smuggling". They use the basic network of telecommunications operators to operate IP telephony business, which constitutes unfair competition, diverting the business income of long-distance telephone operators and disrupting the market order. For users, already by "want to save money, with IP" development into "want to save money, use the underground IP", although it may not have a good quality of service.

Is there a way to find out and stop the existence of these illegal VoIP operations?

Second, the implementation of illegal VoIP detection

1. Detection and analysis

We mainly collect H.323, MGCP, sip three types of protocol VoIP, respectively, in the main call, is called two directions, the same time period will be a number of record collection. Figure 1 is a brief illustration of multiple VoIP connections, ignoring the connection between IP telephony gateways and traditional program-controlled switched networks.

Gateway1, Gateway2 represent IP telephony gateways, which are located in different locations, usually in different cities and even countries. We assume that Gateway1 represents a local media gateway, and that we need to collect data to focus on the gateway that needs to be detected.

Suppose user1 user dials VoIP to call Usera,gateway1 will initiate VoIP connection request to Gateway2, we will record this data, this is the record of call direction. Source IP is Gateway1 IP, the purpose of IP is Gateway2 IP. And at the same time may user2 also in the call Userb,user3 also call UserC, so there will be a number of capture records, although their source IP and destination IP are the same.

Suppose UserA from the field to dial VoIP call User1, from the Gateway2 over the connection request, Gateway1 need to answer, we will record this response, this is called the direction of the record. Source IP or gateway1 IP, destination IP or gateway2 IP. And at the same time may UserB also in the call User2,userc also call User3, so there will be a number of capture records, although their source IP and destination IP are the same.

Detect if any users are using h.233, SIP, MGCP VoIP, or providing VoIP services based on H.323, MGCP, and sip as follows:

(1) Data collection, in some way will flow through the telecommunications broadband network source port number and destination port number of 1718, 1719, 1720, 5060, 2427, 2727 packets collected, that is, including the main call, is called two direction of records. The main contents of the acquisition are source IP, destination IP, source port, destination port, user registration name, session mark, session time;

(2) data upload, upload data to the background analysis system;

(3) Data warehousing, the data file stored in the database;

(4) Data analysis, statistical analysis of the data in the database, combined with some of the pre-set design, get the suspicious list of illegal VoIP;

(5) statistical analysis, according to the analysis of the suspicious list, give the IP phone call details and other related statistical analysis reports.