Opening up networks with JAIN Parlay

The desire for new business growth has been a major driving force towards the development of open network APIs, such as the Parlay API, within telecommunications networks. The Parlay API enables both third parties (external companies, operating outside the security domain of the network operator) and network operators to build new applications that rely on real-time control of network resources. The Java APIs for integrated networks (JAIN^TM) Community is defining a Java version of the Parlay API to bring the benefits of the Java language to the Parlay API, and to promote industry-wide adoption of the Parlay API. This article describes the background and rationale behind the work of the Parlay Group, together with the characteristics, structure, and capabilities of the Parlay API. The benefits that Java and the JAIN Community bring to the Parlay API are then explored. A technical overview of the Java version of the Parlay API, referred to as the JAIN Parlay Edit Group API, is given and illustrated using example sequence diagrams. The article concludes by taking a look at what additional features may be added to the API and the implementation activities that lay ahead     

JAIN: a new approach to services in communication networks

JAIN^TM, a set of integrated network APIs for the Java ^TM platform, provides a framework to build and integrate solutions (or “services”) that span across packet (e.g., IP or ATM), wireless, and PSTN networks. The objective of JAIN is to provide service portability, convergence, and secure access (by services residing outside of the network) to such integrated networks. JAIN is defined and specified by a large number of participating communication companies (the JAIN Community), and according to a well-documented process (the Java Community Process or JCP). The objective of the JAIN Community is to create an open market for services across integrated networks using Java technology. The authors provide the JAIN business case. They then summarize how the JAIN Community works, and introduce how the JAIN Community is organized. They also explain how separate JAIN work items fit together. In particular, they provide the rationale for the currently supported levels of abstraction (in terms of session/call signaling models) in JAIN, and look at possible implementation scenarios     

JAIN protocol APIs

JAIN envisions the creation of a number of Java APIs that abstract the details of networks and protocol implementations, and allow for the development of portable applications. The JAIN Protocol Experts Group (PEG) will focus on developing Java APIs for protocols used in telephony, INs, wireless networks, and the Internet. The PEG is organized into an SS7 subgroup and an IP subgroup. The article provides an introduction to PEG. It next describes the JAIN SS7 APIs. It then describes the JAIN IP APIs. The article also explains how JAIN SS7 and IP APIs can be leveraged for the converged SS7-IP networks of the future and describes the JAIN PEG roadmap     

SIP协议下Parlay业务生成环境的研究及实现

开放式API（如Parlay、JAIN等）将网络资源向第三方开发商开放，电信新业务的开发变得快速、有效、方便灵活，然而使用更高级的抽象业务生成环境（SCE）将会使业务的开发变得更快更有效。给出了SIP（会话初始化协议）协议下，Parlay API业务生成环境的总体结构和映射，并在此结构上应用一个业务实例来分析它的相关过程。尽管它仅支持发起呼叫业务和生成业务的范围仍然有限，但它是非常有应用前景的。     

Ubiquitous Information Services with JAIN Platform

To provide responsive information services in a ubiquitous computing environment, service software and system development are indispensable. A component-based ubiquitous information system with a JAIN (Java APIs for Integrated Networks) platform to achieve seamless transmissions and reach-everywhere communications was designed in our research. In this development, numerous ubiquitous service modules were identified: location management, roaming, mobile IP and WAP networking. These component-based network modules were constructed using a component composition language with component specification and interface definition, running on top of a distributed service architecture using a JAIN platform to distribute the ubiquitous information services to mobile users. Two applications, Wireless-Application-Protocol (WAP) Mail and Video-on-Demand (VoD) services, show that the JAIN-like platform with the developed networking components effectively fills the gap for application developers between mobile appliances and various kinds of ubiquitous information services.     

Building blocks for IP telephony

Convergence between the existing telephone networks and data transfer over the Internet not only demands that new software be written to handle telephony applications which span both networks, but also makes new and innovative applications possible. Rather than writing these applications from the ground up, it would be helpful to have a relatively high-level API on which to prototype new applications. In this article we describe a set of Java packages developed at Cornell University to accomplish this purpose. The software's name is ITX; it is available for download at no charge, and includes sample applications and documentation     

Handoff priority scheme with preemptive, finite queueing and reneging in mobile multiservice networks

A scheme supporting voice and data calls with some grade of service (GoS)¹ guarantee in mobile multiservice networks is proposed. In this system, voice calls have preemptive priority over data calls. Preempted data calls can wait in a queue for a random patience time after which they leave the queue. A data call can be preempted only if there is space left in the finite size queue. To assess the performance of this system, an analytical model is given and performance metrics such as call blocking, call dropping and call non‐completion probabilities are investigated. Although this scheme is a generic model, it can be easily adapted to take into account the specific definitions of practical and commercial data service standards in wireless mobile networks such as GPRS or DECT. This revised version was published online in June 2006 with corrections to the Cover Date.     

Resource sharing for book-ahead and instantaneous-request calls

In order to provide an adequate quality of service to large-bandwidth calls, such as video conference calls, service providers of integrated services networks may want to allow some customers to book their calls ahead, i.e., make advance reservations. We propose a scheme for sharing resources among book-ahead (BA) calls (that announce their call holding times as well as their call initiation times upon arrival) and non-BA calls (that do not announce their holding times). It is possible to share resources without allowing any calls in progress to be interrupted, but in order to achieve a more efficient use of resources, we think that it may be desirable to occasionally allow a call in progress to be interrupted. (In practice, it may be possible to substitute service degradation, such as bit dropping or coarser encoding of video, for interruption.) Thus, we propose an admission control algorithm in which a call is admitted if an approximate interrupt probability (computed in real time) is below a threshold. Simulation experiments show that the proposed admission control algorithm can be better (i.e., yield higher total utilization or higher revenue) than alternative schemes that do not allow interruption, such as a strict partitioning of resources     

基于Parlay API的多方呼叫业务的设计与仿真实现

文中分析了3G蜂窝移动通信网络中增值业务设计的重要性,提出了一种基于Parlay API技术的3G移动通信网络多方呼叫业务的程序设计方法,并在NRG仿真器上对该业务进行了仿真实现,验证了遵循parlay组织提出的开放API开发电信增值业务的可行性和简单性.最后,分析了3G网络中多方呼叫业务的实际运作效果及其市场价值.     

Call admission control for capacity-varying networks

Many networks, such as Non-Geostationary Orbit Satellite (NGOS) networks and networks providing multi-priority service using advance reservations, have capacities which vary over time for some or all types of calls carried on these networks. For connection-oriented networks, Call Admission Control (CAC) policies which only use current capacity information may lead to excessive and intolerable dropping of admitted calls whenever the network capacity decreases. Thus, novel CAC policies are required for these networks. Three such CAC policies are discussed, two for calls with exponentially distributed call holding times and one for calls whose holding time distributions have Increasing Failure Rate (IFR) functions. The Admission Limit Curve (ALC) is discussed and shown to be a constraint limiting the conditions under which any causal CAC policy may admit calls and still meet call dropping guarantees on an individual call basis. We demonstrate how these CAC policies and ALC represent progressive steps in developing optimal CAC policies for calls with exponentially distributed call holding times, and extend this process to the more general case of calls with IFR call holding times.     

Call admission control for voice/data integration, in.broadband, wireless networks

This paper addresses bandwidth allocation for an integrated voice/data broadband mobile wireless network. Specifically, we propose a new admission control scheme called EFGC, which is an extension of the well-known fractional guard channel scheme proposed for cellular networks supporting voice traffic. The main idea is to use two acceptance ratios, one for voice calls and the other for data calls in order to maintain the proportional service quality for voice and data traffic while guaranteeing a target handoff failure probability for voice calls. We describe two variations of the proposed scheme: EFGC-REST, a conservative approach which aims at preserving the proportional service quality by sacrificing the bandwidth utilization, and EFGC-UTIL, a greedy approach which achieves higher bandwidth utilization at the expense of increasing the handoff failure probability for voice calls. Extensive simulation results show that our schemes satisfy the hard constraints on handoff failure probability and service differentiation while maintaining a high bandwidth utilization.     

Modeling and Simulation of Mixed Queueing and Loss Systems

In this paper, we investigate a multi-rate network in which wide-band calls are allowed to wait if insufficient resources are available at the time of the call arrival. On the link level, an analytical model is presented and simulations have been carried out on the network level. The results indicate that allowing a few wide-band calls to queue can give a significant improvement in performance in terms of network revenue , as well as a means to level out the blocking probabilities of the different traffic classes. This improvement becomes significant when the service discipline of the waiting calls (of different bandwidth requirements) is adaptive in the sense that longer queues get served first. This observation motivates the investigation of the impact of various buffer space assignment and queueing disciplines on network revenue and call blocking probabilities. The study of such mixed delay and queueing networks is motivated by its possible applications to traffic problems in future Broadband Integrated Services Digital Networks as well as in multi-rate cellular radio networks.     

WLAN中基于效用的呼叫接纳控制策略

 为了在802.11的网络中提供服务质量(QoS)支持,IEEE 802.11 Task Group E提出了EDCF协议.然而EDCF只能提供业务区分服务,并不能提供服务质量(QoS)保证.为了能在重负载下提供QoS保证,在WLAN中加入呼叫接纳控制(CAC)机制是非常必要的.本文首先提出了一个新的3维Markov模型对非饱和状态下EDCF的吞吐量和平均接入时延进行了分析.并在此基础上,提出了一种基于效用函数的CAC策略,它可以使网络的总收益达到最大.最后通过大量仿真验证了所提出的CAC策略的有效性.     

综合智能网实现技术

结合文献理论的研究，采用与固定电话智能网对比的研究方法，分析了综合智能网的特点、组成结构和运用前景，并提出了两段式实现设想：第一步，在服务的底层调用应用编程接口(API)，将多种电信协议进行映射；第二步，实现业务控制点(SCP)的软件架构向开放服务结构(OSA)过渡。在对服务需求的增长和市场竞争日益剧烈的背景下，电信运营商需要一个能有效地利用原有的网络，同时能为多个网络的用户提供统一的业务解决方案。综合智能网是电信运营商的一个比较理想的选择。     

A Service Management Framework for M-Commerce Applications

Mobile commerce (m-commerce) refers to an ability to conduct wireless commerce transactions using mobile applications in mobile devices. M-commerce applications can range from as simple as an address book synchronization to as complicated as credit card transactions. M-commerce is expected to grow dramatically in the near future supporting simple to complex commerce transactions. Even though the Wireless Application Protocol (WAP) is designed to facilitate the development of wireless applications, it will not be sufficient to handle complex business transactions that require cooperation of different service applications. In order to handle these complex mobile commerce transactions efficiently, an intelligent, robust and scalable framework that provides diverse m-commerce services is required. This paper describes in detail such an m-commerce framework based on the Java Intelligent Network Infrastructure (JINI) and Wireless Applications Protocol (WAP).     

Call admission control for non‐geostationary orbit satellite networks and other capacity‐varying networks

Many networks, such as non‐geostationary orbit satellite (NGOS) networks and networks providing multi‐priority service using advance reservations, have capacities which vary over time for some or all types of calls carried on these networks. For connection‐oriented networks, call admission control (CAC) policies which only use current capacity information may lead to excessive and intolerable dropping of admitted calls whenever the network capacity decreases. Thus novel CAC policies are required for these networks. We present the admission limit curve (ALC) and prove it is a constraint limiting the conditions under which any causal CAC policy may admit calls and still meet call dropping guarantees on an individual call basis. The ALC also leads to a lower bound on the call blocking performance achievable by any causal CAC policy which provides dropping guarantees to individual calls. Also, we introduce a new CAC policy which uses knowledge of future capacity changes to provide dropping guarantees on an individual call basis and which achieves blocking performance close to the lower bound. Copyright © 2000 John Wiley & Sons, Ltd.     

Admission Control Algorithms for Revenue Optimization with QoS Guarantees in Mobile Wireless Networks

We propose and analyze call admission control algorithms integrated with pricing for revenue optimization with QoS guarantees to serve multiple service classes in mobile wireless networks. Traditional admission control algorithms make acceptance decisions for new and handoff calls to satisfy certain QoS constraints such as the dropping probability of handoff calls and the blocking probability of new calls being lower than a pre-specified threshold. We analyze a class of partitioning and threshold-based admission control algorithms that make acceptance/rejection decisions not only to satisfy QoS requirements but also to optimize the revenue of the system by taking prices and arrival/departure information of service calls into account. We show that for a “charge-by-time” pricing scheme, there exist optimal resource allocation settings under which the partitioning and threshold-based admission control algorithms would produce the maximum revenue obtainable by the system without sacrificing QoS requirements. Further, we develop a new hybrid admission control algorithm which outperforms both partitioning and threshold-based admission control algorithms over a wide range of input parameters characterizing the operating environment and service workload conditions. Methods for utilizing of the analysis results for realtime admission control for revenue optimization with QoS guarantees are described with numerical data given to demonstrate the applicability.     

Joint resource allocation for WLAN&WCDMA integrated networks based on spectral bandwidth mapping

Next wireless network aims to integrate heterogeneous wireless access networks by sharing wireless resource. The spectral bandwidth mapping concept is proposed to uniformly describe the resource in heterogeneous wireless networks. The resources of codes and power levels in WCDMA system as well as statistical time slots in WLAN are mapped into equivalent bandwidth which can be allocated in different networks and layers. The equivalent bandwidth is jointly distributed in call admission and vertical handoff control process in an integrated WLAN/WCDMA system to optimize the network utility and guarantee the heterogeneous QoS required by calls. Numerical results show that, when the incoming traffic is moderate, the proposed scheme could receive 5%?C10% increase of system revenue compared to the MDP based algorithms.     

Enabling seamless multimedia wireless access through QoS‐based bandwidth adaptation

Effective support of real‐time multimedia applications in wireless access networks, viz. cellular networks and wireless LANs, requires a dynamic bandwidth adaptation framework where the bandwidth of an ongoing call is continuously monitored and adjusted. Since bandwidth is a scarce resource in wireless networking, it needs to be carefully allocated amidst competing connections with different Quality of Service (QoS) requirements. In this paper, we propose a new framework called QoS‐adaptive multimedia wireless access (QoS‐AMWA) for supporting heterogeneous traffic with different QoS requirements in wireless cellular networks. The QoS‐AMWA framework combines the following components: (i) a threshold‐based bandwidth allocation policy that gives priority to handoff calls over new calls and prioritizes between different classes of handoff calls by assigning a threshold to each class, (ii) an efficient threshold‐type connection admission control algorithm, and (iii) a bandwidth adaptation algorithm that dynamically adjusts the bandwidth of an ongoing multimedia call to minimize the number of calls receiving lower bandwidth than the requested. The framework can be modeled as a multi‐dimensional Markov chain, and therefore, a product‐form solution is provided. The QoS metrics—new call blocking probability (NCBP), handoff call dropping probability (HCDB), and degradation probability (DP)—are derived. The analytical results are supported by simulation and show that this work improves the service quality by minimizing the handoff call dropping probability and maintaining the bandwidth utilization efficiently. Copyright © 2006 John Wiley & Sons, Ltd.     

A dynamic call admission scheme for VBR traffic in ATM networks

The role of call admission control (CAC) in high-speed networks is to maintain the network utilization at a high level, while ensuring that the quality of service (QoS) requirements of the individual calls are met. We use the term static CAC to describe schemes that always allocate the same bandwidth to a specific group of multiplexed calls, independent of the other traffic sharing the link. Dynamic CAC, on the other hand, denotes a scheme in which the bandwidth allocation to a group of calls sharing a queue is influenced by the traffic in other queues destined for the same outgoing link. We propose a generic dynamic call admission scheme for VBR and ABR traffic whose aim is to reduce the blocking rate for VBR calls at the expense of a higher blocking rate for ABR calls. Our scheme is generic because it builds up on a pre-existing static scheme, e.g., one based on a simple notion of effective bandwidth. Our simple approach results in a significant reduction of the blocking rate for VBR traffic (several orders of magnitude), if the bandwidth requirements of a single call are a reasonably small fraction of the link capacity. At the same time, the deterioration of service for ABR traffic can be contained. This revised version was published online in August 2006 with corrections to the Cover Date.