Next-generation Internet protocols led by WLCP of SIP--BEA Systems (1)

This article will introduce the value of the communication platform. It is of great significance not only to telecom companies, but also to any companies that develop enterprise-level applications.

With the release of BEA WebLogic Communication Platform (WLCP), BEA began to enter the Communication Platform field on a large scale. BEA's new platform brings capabilities that used to strictly fall into the field of telecom network programmers to the J2EE developer community. This provides many advantages, such as significantly reducing the time and cost required to build a telephone service and providing the ability to create new telephone-related service types, which was previously impossible) -- all these are completed through Java, J2EE, and Web Service technologies.

From the perspective of the user interface, the user experience is rapidly changing. It is also very important to understand this point. 1 shows that the UI experience has evolved from the rich fat client front-end applications in the client-server application era to a simpler HTML page. HTML-based applications are easy to build and maintain through servlet and JSP models-View-control architecture, but they are basically text-based, it is rarely integrated with a variety of collaborations used by some Windows-based applications, such as various VB controls that can be integrated with audio and video-based media applications.

Figure 1 user experience

More and more people expect Web applications to integrate traditional HTML interfaces with functions such as instant messaging, voice over conventional PSTN phones, VoIP or soft phones, and videos. Session initiation protocol (SIP) can make it a reality. Many people think that SIP is the next important Internet protocol because it brings a new set of media and collaboration capabilities to applications. These new applications are called "aggregate Applications" because they integrate traditional telecom-type capabilities within enterprise applications. They can now include various media such as voice, video, and chat) and application logic such as the UI logic provided by JSP and the business logic provided by EJB ).

The following is an example list of some new aggregate applications supported by SIP, excluding all ):

Real-time video sharing
Instant Voice Messaging
Voice-Video Phone
Video conferencing
Rich Media Enterprise Collaboration
Click-to-call)
Automatic Teleconference
Aggregated call center Communication
People in the telephone industry know that this field is currently filled with a variety of acronyms, including IMS, SIP, PARLY, PARLYX, SMS, PSTN, RBOC, VoIPIP voice transmission) -- and this list is still growing. There are also some important elements, such as registration servers and field servers, which are not described in this article through various channels) used to register users and track their availability. This article is not a comment on "Telecom 101", but I will try to provide a more comprehensive overview so that you can better understand how these things are combined.

Fortunately, BEA's WLCP can help you increase productivity without having to know many terms and technologies. This leads to an important point of view. Based on my discussions with architects and developers, I have come to this point. Many people are impressed that the SIP Server only appears in China Telecom and is dedicated to the definition of the VoIP plan. For details, refer to the VoIP section below ). This is not the case. It is unknown when SIP works in concert with the traditional public switching telephone network PSTN), VoIP or wireless networks. There are some gateways that can use these different transmission technologies to communicate with each other.

Current status of Telecommunication Industry
The telecom industry is undergoing many fundamental changes and is currently showing two completely different trends. A trend requires operators to create new revenue opportunities by creating aggregated video, voice, and data applications, often referred to as "triple play. This is an example of online real-time multimedia and two-way interactive services such as games. Another trend is to continue to work hard to reduce the cost of running the traditional PSTN network and operation, and finally migrate it to a more economical VoIP network.

Fast migration
Optical fiber cables are being connected to homes and enterprises at extremely fast speeds. Several months ago, several fiber cables crossed the road from outside my house-but they were not directly connected to my house. Optical fiber is committed to bringing unprecedented network speeds to workplaces and homes, thus revolutionizing telecommunication and connection technologies. For example, Verizon now uses their FiOS product to provide a speed of 15 megabytes/second. If this speed can be used for new applications, it will produce significant economic benefits. In fact, "Fast household access" is becoming a reality to a large extent.
Telecom companies need to create new services to get away from their competitors, which pushes them to invest in a strategy to make their services better than their competitors. If they plan to continue to use the old vswitch Class 5 and other VPC elements to do this, it is like putting a foot on the accelerator, but putting another foot on the switch is not very effective for winning the competition. So bea wlcp came in handy. It replaces a lot of old-style technology needs and brings J2EE or JEE) the capabilities that developers initially only have in the telecommunications field, as well as the highly specialized skills of "network experts.

VoIP
VoIP is the hardware and software that allows the use of group switching instead of the traditional PSTN to place media calls-voice and others-on an IP-based network Internet. An important advantage of VoIP is that the company avoids the costs and traffic associated with the PSTN. In addition, the infrastructure required to host a VoIP network is based on commercialized hardware and software, while PSTN is built on a largely closed hardware and software system, such as a Class 5 switch. Generally speaking, telecommunications companies will have both PSTN and VoIP networks, which will be able to interoperate in the foreseeable future, but will eventually be transferred to IP-only networks.

Why communication platforms
The world has changed, and there is a strong demand to extract telecommunications capabilities from the pure network workroom and provide them to common developers to create new types of aggregate applications. As mentioned above, this is generally called the aggregation between traditional telecom and enterprise application development. Bea wlcp provides developers with a group of industry-leading tools to program in common environments such as J2EE, Java, and Web services.

By the time of writing this article, WLCP has two components: WebLogic SIP Server and WebLogic Network keeper, as shown in figure 2. Although this article focuses on WebLogic SIP Server, WebLogic Network keeper is also an important part of WLCP. When a layer is required to protect and mediate Network and Network traffic, the Network keeper helps to provide more underlying Network control, such as protocol adapters and support for ParlayX, parlayX is a specification for enabling telecommunication network capabilities to applications.

Figure 2 WLCP component

Therefore, these new core telecom capabilities are combined with the rest of the BEA platform's WebLogic Server, WebLogic Portal, and WebLogic Integration to form all the tools for building aggregate services:

Integration with existing legacy applications;
Completely part of the service-oriented architecture SOA)
Can be displayed in any type of browser or device, also known as multi-channel transmission;
Provides a personalized view of applications through the WebLogic Portal.
At present, the capabilities of these combinations are generally referred to as the Service Delivery Platform, SDP ). This example blur the differences between wireless, wired, VoIP, and Web-based transfer channels. In fact, these channels can now work collaboratively in an unprecedented manner.

What is
In short, SIP is a protocol provided by IETF in RFC 3261. It provides the Signaling System 7, SS7, which previously existed in the No. 7 Signaling System) the signaling capability in the terms of the Protocol. SIP Servlet API has been incorporated into the JSR-116 of the Java language-see: www.jcp.org/en/jsr/detail? Id = 116 ). WebLogic SIP Server is an Application Server that supports the SIP Servlet API. There are obvious similarities between the SIP Servlet and the HTTP Servlet because they share some of the same design and encoding principles. In fact, they all extend javax. servlet. GenericServlet. There are few classes, interfaces, and methods in the SIP Servlet specification, which allows people to easily and quickly master their basic knowledge.

The operation of SIP is to "ping" other devices. In essence, it is to execute an INVITE message request to establish a session between devices. This is usually called Call Control-creating and cutting off media streams, such as phones. A session can be of almost any type and is not so much a SIP protocol function as a device function. This session can be a call that invites another person to open a voice media stream, or an application that requests a video media stream to support videos. Media streams, such as Real-time Transport protocols (RTP), are defined as a standardized grouping format for transmitting audio and video and other media over the Internet ), and independent from the SIP signaling.