Open application programming interface PARLAY API
2003-12-16
Shi Feng Yang Yuchun
Beijing University of Posts and Telecommunications Exchange Technology and Communication Network National Key Laboratory
Abstract This article summarizes the model of traditional smart network to provide value-added services, pointing out the advantage of the Parlay API as an open application programming interface. And introduced the development of the Parlay organization, the architecture and interface functions of the Parlay API, and how to use the Parlay API to shield the underlying network development business, the last example details the process using the Parlay Mobility API to implement mobile location services.
Keywords Parlay API Mobile location business open business platform intelligent network Next generation network NGN
I. Introduction
The new generation of telecommunications network is converted from the traditional telecommunications network to IP telecommunications network, which will be done on the basis of summarizing the experience of traditional telecommunications networks. This kind of telecommunications network is an open platform based on IP technology and will bring new services to the telecommunications network, and have huge market space. Existing IP networks have been commonly used to carry telephone services, data services, conference television. This trend marks the future telecommunications network is a business-driven network, and the open business interface is the basis for providing rich business in a new generation of telecommunications network.
Second, open business interface
1. Comparison with traditional intelligent networks
The intelligent network is a traditional telecom value-added service providing, which provides value-added services, SCP and SSP interact with the INAP protocol through the SCP control SSP. Although after years of development, smart network technology has been very mature, and is widely used in various call card services, but the smart network itself has a defect with its designs. These defects are mainly reflected in their business development and providing ways, and the presentation of a new business has been greatly shortened than providing business directly on the switch, but its business generation depends on intelligent network equipment providers, and Its business is targeted by the mass market, rarely for corporate users and individual users.
2. Advantages of open business interface
Compared to traditional smart networks, the use of open application programming interfaces provide a possibilities for business providers for easy development services, which can provide users with a more rich business based on network capabilities. The purpose and significance of the open application programming interface is to use the business development interface to publicize, abstract, so that third-party developers can also join the developer ranks of communication value-added services; and block the specific agreement of the underlying network, make third-party developers There is no need for too many specialized agreement; eventually achieve fast, cheap development and deployment of new business purposes.
The openness of the new generation of programmable business interface technology is mainly reflected in two points: First, business expansion. On traditional telecommunications networks, access control, media transmission control, and call processing, intelligent services, application services, and business operations are done by different business platforms and protocols. In this way, the telecom service can be expanded flexibly. The second is the exchange of business. The telecommunications service is composed of modules, and users can freely define, any business can achieve new services by increasing the module, which can produce personalized services for different users.
3. Current status of open business interface
At present, using public, open business interface systems to build a comprehensive business support platform has become one of the hotspots in telecommunications. There are two representative specifications in the development of business interface specifications: PARLAY and JAIN. They are not developed by standardized organizations, but more and more support are being obtained. In particular, PARLAY organizations developed the Parlay specification, which has become the most influential API norm in the industry, and has been recognized by most standardized research institutions and vendors, which is likely to become a standard interface open from the future.
Third, Parlay Overview
The PARLAY interface normative system is the current most vital open service interface standard specification in the world. In addition to the feature of the traditional open signaling control interface, the main features of the Parlay interface can be used to support external application security access network internal resources. This broadens the application range of network intelligence to many software developers and business providers including device providers and traditional operators. The PARLAY interface will open the closed door of the telecommunications network through abstract network capabilities, create a new telecom business market and value chain. 1. Parlay group development
Parlay organized in March 1998, jointly established by BT, Ulticom, Microsoft, Nortel and Siemens, mainly researching network interface specifications for external applications to access security network internal resources, and its purpose is based on next-generation communication network development The demand, proposes a series of APIs into a set of interfaces of the underlying communication network, which is easy to understand, and has a big role in the opening of the communication network and the internet interoperability, so it has been widely concerned about the industry, and the development is very fast. At present, its members have almost included well-known companies in all industries. The Parlay organization is to open the ability of telecommunications to develop and provide advanced telecommunications services to market participants in the largest range. To this end, the organization has developed a set of open, independent APIs for third-party business development and deployment, called the Parlay API (PARLAY specification).
From December 1998, Parlay API 1.0 specification has been launched until the Parlay API version 4.0. The API defined by the Parlay Study Group is now a reference to most industrial organizations. It is likely to be a standard interface for future network open.
2. Parlay API defined business models and features
Traditionally, network operators, combined with network equipment vendors, design, development, deployment, and management operations in voice and data applications. These applications typically adapt to large-scale business such as market demand, such as virtual private network (VPN), 800, etc. Small-scale applications with less demand and shorter life cycle are difficult to neglect by network operators in business: network operators are not considered to be aware of a small number of users using several days of specific applications.
In many ways to implement third-party applications, the Parlay organization uses an Open Application Programming Interface (API) method to solve this problem. The power of the API method is to provide a clear division between the Parlay API between the network operator and third-party application vendors by defining a set of secure scalable real-time interfaces. External or third-party companies are typically typical end users, business vendors, businesses, and other network operators. Parlay API provides access and control core for third-party applications outside the trusted network operator space. Standard method for network resources.
3. PARLAY API implements business driver
Parlay API defines four commercial roles, all business activities are launched around them: network operators, service providers, third-party business providers, and business developers.
The Parlay interface is used to provide value-added telecom services to bring more business users to operators, thereby increasing network access quantities and usage, get more operational revenue. Let third-party business developers and providers enter telecommunications business development and provide the field to increase business types provided by operators, further providing operators' competitiveness, and improve user loyalty.
Using the Parlay interface to make value-added business development can further reduce the technical threshold. Since the technology adopted by the PARLAY interface is general computing technology, the future may also develop to the Web Service, and the traditional intelligent business can also develop intelligent services than using the traditional intelligent business using the ASN.1 and INAP protocol. In addition, the PARLAY interface has designed a powerful network access control function, which greatly reduces the correctness of the business, which is conducive to more business developers; Parlay interface shields specific underlying network details through abstract interfaces, and the development business is more convenient, Really realize business drivers. The Parlay interface also provides a third-party business developer including the vast number of ISPs, providing opportunities to enter the telecom value-added business market, thereby conducive to the production of a large number of new business, and the traditional value-added business market is monopolized for minority intelligent network equipment providers. .
Fourth, Parlay API architecture
The Parlay API can be considered as composed of two parts: Framework and Services, as shown below. The framework of the figure mainly provides the security and management support capabilities necessary for business interfaces. Services package various specific network service capabilities, providing an abstract view of network capabilities to business developers. Application is the client using these two capabilities.
figure 1
The structure in Figure 1 embodies a set of business models for future communication markets proposed: Framework as a platform provided by network operators, with the role of trading grounds and middlemen in the entire commercial model. Service providers register call control, mobile management, etc., to the framework of various underlying networks, and third-party business providers to order these services through the framework and use the API interfaces provided by these services to develop a variety of value-added services.
1. Frame interface part (Framework)
The framework provides the necessary security authentication and management capabilities to ensure the openness, security, manageability, and elasticity of the business interface. The frame interface of the PARLAY API version 4.0 contains four basic modules (trust and secure access modules, business discovery and registration modules, integrity management modules, and business contract management modules) provide authentication and authentication, business registration, ordering and Find, integrity management, etc. Below we detail the functional division of these three modules.
(1) Trust and secure access module
This module provides a series of functions such as initialization access, authentication, service access between applications and network services, composed of ipinitial, ipauthentication, and ipaccess interfaces. Each interface includes two parts: application side and network side, providing mutual call between client applications and network services.
a) ipinitial interface
This interface is the function of the first access point provided by the framework to the client application, providing initialization authentication, requiring access.
b) ipAuthentication interface
The interface provides authentication, including: authentication, abandonment, etc. Handling mutual authentication between Client and frameworks.
c) iPaccess interface
This interface provides functions of accessing the Parlay service, including: obtaining a reference to other framework interfaces, signed business uses protocol, terminating business use protocol, terminating access, etc. The interface provides some ways to enable the Client to retrieve and get the reference to the framework, or release the reference and termination of access.
(2) Business discovery and registration module
This module provides a dynamic lookup discovery and dynamic registration of the business. This module consists of an interface such as IPServicediscovery, IPServiceRegistration.
a) ipserventicediscovery
This interface provides findings and discovery features for all registered Parlay services in the frame. Including: Lists all business types, describing business types, selecting business, etc.
b) ipserviceRegistration
The interface is called by the Parlay service to complete the service registration function. Including: registration, announcing business available, logout, etc.
(3) Integrity Management Module This module provides monitoring and management functions for each business and customer application. This module consists of IPFaultManager, IpHeartBeatmgmt, iPloadManager, Ipoam and other interfaces.
a) ipfaultmanager (IPFWFAULTMANAGER)
This interface is used for troubleshooting, and the application can require the framework to test whether a service is available; apply (service) to the framework (application) unavailable; application (service) to the framework or a service (application) Fault statistics, etc.
b) ipheartbeatmgmt (ipfwheartbeatmgmt)
This interface is used for heartbeat management, has enabled / ceased hops to monitor or change the role of heartbeat intervals. IpheartBeat uses synchronous method to determine if the other party is active.
c) iPloadManager (IPFWloadManager)
This interface is used for load control, and the application can require a framework or a service (application) to report the load; register load control: Notifications are obtained when the load level changes.
d) ipoam (ipfwoam)
This interface is used to query system time, etc.
(4) Business contract management module
This module provides the service contract function between the application and the framework. This module contains only an IPServiceAgreementManagement interface, and the implementable features include applying / abort using services, initialize the protocol based on the application access, and both sides signed the protocol.
2. Service interface part (Service)
Services include various capabilities, such as call control, mobile location service, account management service, user interactive service, Terminal Capability Management, Crest Service, etc. Where call control services, user interaction services, and mobile location services are the more important integration sets provided by the PARLAY API, using these APIs to develop call related and call-independent services. Several more important services will be described below.
(1) Call Control Service
PARLAY API Call Control Services include a normal call control service (GCCS: General Call Control Service), Multimedia Call Control Service (MMCS: MultiMedia Call Control Service), Multimedia Call Control Service (MPCCS: MultiParty Call Control Service), Multimedia Call Control Service (MMCS: MultiMedia Call Control Service), and Conference Call Control Services (CCCS: Conference Call Control Service).
The interfaces are respectively referred to as applications and services, respectively, respectively, indicated by IPAPP- and IP.
The interface includes three parts: application logic, is the core processing logic of the entire application; the callback object on the application side is a callback interface that accepts the event notification of the server side object; the object side object, reflects the underlying network Call, application logic to intervene calls for the underlying network by calling the methods of these objects.
In the call control service, the Callback mechanism is used between the application and the call control service (Call Control Service) to notify the underlying network, and the application side has a callback object to accept the event report. The application can control the call in the underlying network by calling the method of the server side object. In addition, MMCC is inherited from MPCC, and CCCS inherits MMCC, as shown in Figure 2:
figure 2
(2) User interactive service
The user interaction (UI) interface is an interface to interact with the end user. Parlay's User Interactive Service (GuIS) is represented by the following objects:
a) ipuimanager
Provide management capabilities for user interaction services, such as creating ui, uicall, activation event notification, etc.
b) ipui
User Interactive Services To send, collect information to end users, and UI objects allow applications to complete information interaction without restrictions on other services;
c) ipuicall
Inherited from IPUI, therefore has all the ability of IPUI, in addition to strengthening the processing capability of short messages, record, deleting messages.
The difference between IPUICALL and IPUI is that IPUICALL is associated with an abstract object such as call (call) or call legs, and IPUI is associated with a particular address, so the way is used.
(3) Mobile location service (Mobile Service)
The mobile location service interface provides services related to the location and status of the mobile user. Compose from the following objects:
a) User location:
Provide basic geographic services, composed of IPUserLocation and iptriggereduserLocation: where IPUserLocation provides management functions, the writer of the application can get geographic location information by this interface; and iptriggereduserLocation extends from the IPuserLocation interface, can trigger location reports .
b) User Location Camel
Provide information related to the network such as a VLR number, a cell identification, and the like.
c) User Location Emergency
In the emergency call, the network automatically locates the position of the caller and reports the corresponding application.
d) User status
Provide a state of fixed-line, movement, or IP phone users, can trigger reports when the status changes.
(4) Ordinary news service
Application can be received, sent, stored, store messages (voicemail or email), the object included in this service interface is as follows:
a) Messaging Manager:
Provide management functions, applications can open the mailbox or set when new messages arrive.
b) Mailbox:
image 3
Provide operations such as managers such as management folders and messages. Mailbox Folder: Provides operations such as the folder such as open, query, delete messages, and more. (See Figure 3)
c) Message:
Provide management of messages such as query properties, etc.
(5) Terminal capability query service
Providing a way to query terminal capabilities, only one method getterminalcapabilities.
(6) Account Management Service
Provide the application to the account monitoring method, making the application set, cancel the event notification when the billing is related to the billing; the balance of the query account, etc.
(7) billing service
The use of the application will be based on the application, which may be used by the user, or may be other people pay. The billing session uses a serial Request-Response mode. Compose from the following two objects: a) Charge Manager
Have management function, create a billing
b) charging session
Provide trading operations between vendors and users, application writers can perform direct and prepaid bills to users through this method.
(8) Data session control service
Provide the application of the data session for the application, consisting of the following two parts:
a) Data session manager
Management functions, including setting, modify, query, and unless the notification rules for related events; you can manage multiple Data Session.
b) Data session
Provide control of data sessions, including: connection, release, monitoring, and billing; can only be managed by a Data Session Manager.
5. Use the Parlay API development business
Use standard Parlay interfaces to provide rich business, such as multimedia conference services, voice mailbox services, and mobile location services, etc. Third-party business developers can also develop a variety of value-added services suitable for users based on market demand, and the provision of this business can be more fast and fast. Parlay API is located in the next generation network, as shown below: Figure 3, the PARLAY gateway is located on the underlying network, responsible for mapping the Parlay API as a specific network protocol, and can develop according to different network capabilities Business development platform.
For example, by a Parlay Gateway, the application developers can use the Parlay API's Mobility Ability to develop a variety of mobile data services based on mobile networks. Below, we introduce how to develop mobile locating services using the Parlay Mobility API in a specific example.
1. PARLAY MOBILITY service type
(1) User Location
User Location Service (UL) provides a general location service. UL allows applications to obtain geographic locations and status of fixed, move, and IP-based telephone users. Using UL functions, applications can request information such as plane position, altitude, terminal type (fixed, mobile, or IP).
(2) User location Camel Service (User Location Camel)
The user location Camel Service (ULC) provides geographic information based on location information related to the network, rather than geographic information obtained by the user location service UL. It supplements UL, providing information related to network. With ULC functions, applications can request VLR numbers, location area identity, global cellular identity, and other mobile phone special location information. This kind of business is used widely.
(3) User Location Emergency Call Service (User Location EMERGENCY)
There are still some special features in the User Location Emergency Service (ULE) to handle emergency calls. With UL function, you can get information such as plane position, altitude, and the user of the emergency call service is identified by the combination of userid, naesrd, naesrk, and IMEI. Only when the user of the emergency call service initiates emergency call business in North America, NAESRD, NAESRK and IMEI are only available.
(4) User Status Service (User Status)
User Status Service (US) provides a general user status service. US allows applications to get status of fixed, move, and IP-based telephone users. If it is a mobile user, the application can also get the status of the mobile phone (up to, not arrival or busy). 2. PARLAY MOBILITY request method
The third-party business developer uses the Mobility business feature, which is nothing more than obtaining information about the location of the user, the network, user terminal status, etc., has four requests.
(1) Triggered Request
The application can set trigger conditions. When the trigger condition is satisfied, the Mobility business constantly reports the requested information until the application issues a "stop" message. Applicable Mobility Business Types: UL, ULC, and US.
(2) Periodic Request
The application can set the time interval, and the Mobility service reports the requested information based on this time interval until the application issues a "stop" message. Applicable Mobility Business Type: UL and ULC.
(3) Interacting request (Interactive Request)
After the Mobility service accepts the application request, immediately report the requested information, which is only sent once. Applicable Mobility Business Type: UL, ULC, ULE, and US.
(4) Subscription
This method is only available for ULE, and the application is prior to booking an emergency call service, that is, it is responsible for emergency calls. When an emergency call occurs, the Mobility service issues the corresponding information to the application that subscribes to the emergency call service.
3. PARLAY MOBILITY Business Process Example Figure 4 is a flow of mobile location services implemented using the Parlay Mobility API, which uses the user location Camel Service (User Location Camel) and uses a periodic request.
Figure 4
With the above-mentioned Parlay Mobility API, we can clearly see that the Parlay API is fast and convenient to realize the powerful advantages of new business.
Sixth, conclusions
The next generation network (NGN) is a business-driven network, and the business has become the strongest stimulant. The PARLAY API is necessary to become an indispensable tool for developing business. This paper briefly introduces PARLAY technology, Parlay technology is still in development, which can be expected that when Parlay technology matures and market, it will bring huge development to network applications.
