Interworking Architectures in Heterogeneous Wireless Networks: An Algorithmic Overview

The scarce availability of spectrum and the proliferation of smartphones, social networking applications, online gaming etc., mobile network operators (MNOs) are faced with an exponential growth in packet switched data requirements on their networks. Haven invested in legacy systems (such as HSPA, WCDMA, WiMAX, Cdma2000, LTE, etc.) that have hitherto withstood the current and imminent data usage demand, future and projected usage surpass the capabilities of the evolution of these individual technologies. Hence, a more critical, cost-effective and flexible approach to provide ubiquitous coverage for the user using available spectrum is of high demand. Heterogeneous Networks make use of these legacy systems by allowing users to connect to the best network available and most importantly seamlessly handover active sessions amidst them. This paper presents a survey of interworking architectures between IMT 2000 candidate networks that employ the use of IEFT protocols such as MIP, mSCTP, HIP, MOBIKE, IKEV2 and SIP etc. to bring about this much needed capacity

Validation of the Parlay API through prototyping

The desire within the telecommunications world for new and faster business growth has been a major drive towards the development of open network API. Over the past 7 years several (semi) standardization groups have announced work on network API, including TINA-C, JAIN, IEEE P1520, INforum, 3GPP, JAIN, Parlay. The Parlay group seems most successful in attracting industry awareness with their API, called the Parlay API. The rational behind the Parlay API is that it attracts innovation from third parties that are outside the network operator's domain to build and deploy new network-hosted applications. This also means that the public telecommunication network is opened for niche and short-lived applications as well as for applications that possibly integrate telephones with other terminals such as PC. The Parlay group has successfully passed the first two phases of success, namely publishing their API on the right moment in time and attracting a critical mass within the telecommunication industry with their results. Prototyping the API on a real network execution platform is the only way to show its technical feasibility. Such an exercise was executed internally within Lucent Technologies and raised a number of questions as well as recommendations on both the technical and the semantical behavior for systems that will be interconnected via the Parlay API. We share these results, showing the drawbacks and advantages as well as challenges for this AP

SIMPLEstone: Benchmarking Presence Server Performance

Presence is an important enabler for communication in Internet telephony systems. Presence-based services depend on accurate and timely delivery of presence information. Hence, presence systems need to be appropriately dimensioned to meet the growing number of users, varying number of devices as presence sources, the rate at which they update presence information to the network and the rate at which network distributes the user's presence information to the watchers. SIMPLEstone is a set of metrics for benchmarking the performance of presence systems based on SIMPLE. SIMPLEstone benchmarks a presence server by generating requests based on a work load specification. It measures server capacity in terms of request handling capacity as an aggregate of all types of requests as well as individual request types. The benchmark treats different configuration modes in which presence server interoperates with the Session Initiation protocol (SIP) server as one block

SIMPLEstone: Benchmarking Presence Server Performance

Presence is an important enabler for communication in Internet telephony systems. Presence-based services depend on accurate and timely delivery of presence information. Hence, presence systems need to be appropriately dimensioned to meet the growing number of users, varying number of devices as presence sources, the rate at which they update presence information to the network and the rate at which network distributes the user's presence information to the watchers. SIMPLEstone is a set of metrics for benchmarking the performance of presence systems based on SIMPLE. SIMPLEstone benchmarks a presence server by generating requests based on a work load specification. It measures server capacity in terms of request handling capacity as an aggregate of all types of requests as well as individual request types. The benchmark treats different configuration modes in which presence server interoperates with the Session Initiation protocol (SIP) server as one block

Presence Traffic Optimization Techniques

With the growth of presence-based services, it is important to provision the network to support high traffic and load generated by presence services. Presence event distribution systems amplify a single incoming PUBLISH message into possibly numerous outgoing NOTIFY messages from the server. This can increase the network load on inter-domain links and can potentially disrupt other QoS-sensitive applications. In this document, we present existing as well as new techniques that can be used to reduce presence traffic both in inter-domain and intra-domain scenarios. Specifically, we propose two new techniques: sending common NOTIFY for multiple watchers and batched notifications. We also propose some generic heuristics that can be used to reduce network traffic due to presence

Parlay X Web Services for Policy and Charging Control in Multimedia Networks

The paper investigates the capabilities of Parlay X Web Services for Policy and Charging Control (PCC) in managing all Internet-protocol-based multimedia networks (IMSs). PCC is one of the core features of evolved packet networks. It comprises flow-based charging including charging control and online credit control, gating control, and Quality of Service (QoS) control. Based on the analysis of requirements for PCC, the functionality for open access to QoS management and advanced charging is identified. Parlay X Web Services are evaluated for the support of PCC, and some enhancements are suggested. Implementation aspects are discussed, and Parlay X interfaces are mapped onto IMS control protocols. Use cases of Parlay X Web Services for PCC are presented

IMS signalling for multiparty services based on network level multicast

3rd EURO-NGI Conference on Next Generation Internet Networks. Norwegian University of Science and Technology, Trondheim, Norway, 21-23 may 2007.The standardization process of the UMTS technology has led to the development of the IP Multimedia Subsystem (IMS). IMS provides a framework that supports the negotiation of the next generation multimedia services with QoS requirements that are envisioned for 3G networks. But even though many of these services involve the participation of multiple users in a multiparty arrangement, the delivery technology at network level is still unicast based. This approach is not optimum, in terms of transmission efficiency. In this paper, a new approach is presented proposing to use a network level multicast delivery technology for the multiparty services that are signalled through IMS. The main advantages and drawbacks related with this new approach are analyzed in the article. Finally, as a starting point in the development of the presented solution, a new SIP signalling dialogue is proposed allowing the negotiation of a generic multiparty service, and supporting at the same time the configuration of the corresponding network level multicast delivery service with QoS requirements that will be used in the user plane.Publicad

Open Access to Resource Management in Multimedia Networks

The paper is dedicated to mechanisms for open access to resource management in the Internet Protocol (IP) multimedia networks. First we present the concept of IP Multimedia Subsystem (IMS) and explain the IMS functional architecture, principles of quality of service management and service control in IMS. Then we describe the idea behind the opening of network interfaces for third parties so that others besides the network operator can create and deploy services. Open Service Access (OSA) and Parlay appear to be the technologies for value-added service delivery in multimedia networks. In the paper we take a closer look to the Parlay/OSA interfaces that allow third party applications to access the resource management functions in IMS. OSA "Connectivity Manager" interfaces and OSA "Policy Management" interfaces are considered. Parlay X Web Services interfaces provide a higher level of abstraction than Parlay/OSA interfaces and gain an amazing amount of support among service developers. We address "Applicationdriven Quality of Service" Parlay X Web Service and "Policy" Parlay X Web Service also