PoC业务用户群及市场策略分析

文章在研究中国电信市场环境及当前业务特点的基础上,对PoC业务用户群及市场推广策略进行了探讨.文章认为中国PoC业务市场推广不能照搬美国运营商Nextel的发展模式,必须结合中国具体的电信业务环境加以考虑.在中国市场中,行业用户是PoC业务推广应首先关注的目标,而对于已经使用或未使用专网集群服务的用户,应采取差异化的市场策略.在推广PoC业务的过程中,应重点发展能够带来新的业务量的PoC用户群,同时尽量避免与现有移动电话、短信、语音信箱等业务的竞争.     

一种基于TD—SCDMA网络的PoC业务时延改进方法

PoC（Push-to-talkoverCellular,亦即无线一键通）是一种新兴的基于蜂窝移动通信网络的PTT（即按即说）业务。文章首先介绍了基于TD．SCDMA网络的PoC业务系统结构和基本会话流程,然后重点对其会话时延性能进行了分析,最后在此基础上提出了一种PoC业务会话时延改进方法。     

无线一键通--未来移动增值业务新的亮点

首先介绍了一种基于蜂窝移动通信新业务PoC的概念和主要技术特征,接着重点介绍了PoC的标准化进程及系统实现方案,最后展望了PoC业务的前景。     

PoC数据业务开展的几点思考

文章介绍了基于IMS的PoC业务的特性与市场背景,通过与传统数字集群、移动Fetion以及Skype等业务比较,对PoC业务的客户体验、通信运营、技术支撑等业务开展的关键问题进行了分析和阐述。只有在业务开展中突破其中的瓶颈,PoC业务才能真正成为3G网络中的杀手级应用。     

基于GPRS的PoC系统的设计与实现

本文介绍了PoC这种新型的语音业务及其体系结构,并分析了在现有的GPRS网络上实现PoC业务的体系结构.分析了PoC系统的组网,对PoC系统进行了设计与实现.     

基于UMTS的PoC业务QoS研究

文章首先介绍了UMTS系统端到端的QoS架构及业务的QoS等级分类,然后重点分析了基于UMTS系统的PoC业务的端到端QS保证问题,最后针对PoC业务无线链路传输的时延问题提出了一种降低时延的方法,仿真表明:对于支持IP包压缩的网络来说,该方法可有效优化PoC业务用户体验.     

PoC业务现状及应用前景

PoC业务的基本设计思想是利用现有的GSM／GPRS网络提供分组语音服务，业务逻辑采用了类似现有集群通话的半双工模式，支持一对一、一对多通话。在系统实现上，运营商需要在网络侧引入新的网元，负责PoC用户的业务登记、认证与通话处理，这个新的网元即通常所说的业务网关，与GPRS Gi接口相连。手机终端也需要集成PoC功能，这样终端在PDP Context激活后就能通过SIP建立分组话音进程。PoC与传统GSM电话的比较见表1。     

3G网络PoC标准研究

基于公众蜂窝移动通信网络的PTT业务称为PoC业务.由于PoC业务呼叫建立时间短,能够发起半双工方式的群组呼叫,并且基于3G网络的IMS架构,从而成为未来3G网络中备受瞩目的移动通信业务.本文主要介绍了PoC业务标准发展情况,并结合IMS网络结构对PoC业务发展趋势进行了分析.     

3G移动PoC实现技术

移动一键通(PoC)业务是3G的重要特色业务。PoC的实现有基于PS和基于IMS两种方式。文章从分析PoC的业务特点出发,介绍了PoC业务的功能、协议结构和标准化情况,比较了两种实现方式的实现要点,特别是详细分析了3G环境下基于IMS实现方式的实现机制和流程。最后,对PoC业务的应用和发展作了一个展望。     

PoC在TD-SCDMA中的发展策略研究

文章介绍了如何利用TD-SCDMA的技术特点,优化PoC的性能,以使得PoC达到集群系统类似性能;阐述了在TD-SCDMA上实现PoC业务时,应该采取的演进策略。最后也对TD-SCDMA联盟PoC的进展情况进行了介绍。     

A client‐side design and implementation for push to talk over cellular service

This paper proposes a client architecture for the push to talk over cellular (PoC) service based on the open mobile alliance (OMA) PoC specifications v1.0 release. We show that most standard VoIP modules can be reused for the PoC client, and the VoIP software can be easily extended to support PoC service. Then we present the detailed message flows between the PoC client and other network entities in the PoC system. A PoC client prototype has been implemented in the Industrial Technology Research Institute (ITRI) and National Chiao‐Tung University (NCTU) Joint Research Center. Copyright © 2006 John Wiley & Sons, Ltd.     

A programmable architecture for the provision of hybrid services

The success of new service provision platforms will largely depend on their ability to blend with existing technologies. The advent of Internet telephony, although impressive, is unlikely to make telephone customers suddenly turn in favor of computers. Rather, customers display increasing interest in services that span multiple networks (especially Internet protocol-based networks and the telephone and cellular networks) and open new vistas. We refer to these services as hybrid services and propose an architecture for their provision. This architecture allows for programming the service platform elements (i.e., network nodes, gateways, control servers, and terminals) in order to include new service logics. We identify components that can be assembled to build these logics by considering a service as a composition of features such as address translation, security, call control, connectivity, charging, and user interaction. Generic service components are derived from the modeling of these features. We assure that our proposal can be implemented even in existing systems in return for slight changes. These systems are required to generate an event when a special service is encountered. The treatment of this event is handled by an object at a Java service layer. Java has been chosen for its platform-neutrality property and its embedded security mechanisms. Using our architecture, we design a hybrid closed user group service     

PoC中发言权控制机制的分布式改进

TBCP(talk burst control protocol)是OMA(open mobile alliance)为PoC(push to talk over cellular)系统定义的集中式发言权控制机制,具有单点控制瓶颈等固有缺陷。而在现有的分布式发言权控制机制中,并没有一种机制能够很好地被应用于PoC系统。对TBCP进行了改进并提出了2种分布式发言权控制机制:TBCP/DQ(distributed queue)和TBCP/MQ(mobile queue)。通过分析和仿真,验证了2种新机制能够很好地满足PoC业务的需求,甚至可以推广到所有CMA(collaborative multimedia applications)业务当中。     

Dimensioning and optimization of push‐to‐talk over cellular server

The PoC (push‐to‐talk over cellular) application allows point‐to‐point or point‐to‐multipoint voice communication between mobile network users. The related work over PoC focuses on the performance analysis only and is ignorant about dimensioning a PoC controller to optimize revenue for service providers. In this paper, we dimension a PoC service with the assumption that the network grade of service is provided. The on‐demand sessions should have access priority over pre‐established sessions. A PoC controller should be able to terminate a PoC session based on an optimal timer. Moreover, the number of simultaneous session initiations by a PoC client is also a configurable parameter. We derived relations to provide access priority to special PoC sessions based on available transmit/receive units (TRU) and threshold level. Load sharing expressions are reported for a PoC controller using the Lagrange multiplier technique. A simple relation to control the PoC session timer is proposed. Finally, the derivation of maximum number of allowable simultaneous sessions is depicted using two‐state Markov models. Numerical results have been computed with the corresponding derivation to provide a useful insight into the system behaviour. A PoC service can benefit from these optimal values of our work during the busy hour. Copyright © 2007 John Wiley & Sons, Ltd.     

EuroBridge: communications services for multimedia applications

The aim of the EuroBridge project is to provide a uniform communication service platform. This platform will provide true multimedia multipoint services including interactive video conferencing and store-and-forward data services. The project will enhance selected OSI application layer services to provide them with multimedia capabilities. Selection of the initial services as well as the identification of necessary functional enhancements were based on actual user requirements. To support the dedicated communication requirements imposed by multimedia and multipoint applications, the lower layers of the OSI model will be enhanced accordingly. This includes designing and implementing new lightweight session and presentation protocols, respectively. Furthermore, high-speed transport protocols will be utilised. The actual protocol stack used will be configured dynamically depending on the requested quality of service. Support of multicast capabilities will be a crucial issue. The service platform is being implemented to run on top of different high-speed networks, including FDDI and DQDB     

下一代网络业务开发和控制平台的标准化研究

下一代网络对业务的快速开发和部署需求越来越迫切,需要在网络能力开放的基础上进一步开放业务的能力.本文对与下一代网络的业务开发和控制相关的两大主要标准化组织3GPP和OMA进行了详细研究,阐述了3GPP IMS作为下一代网络业务开放的统一的控制平台的工作机制,分析了OMA业务环境OSE的概念和思想,并详细分析了OSE与IMS的关系.最后以PoC业务为例阐明了下一代网络的业务开发模式及业务之间的调用关系.