A SIP-based OSGi device communication service for mobile personal area networks

The Open Services Gateway Initiative (OSGi) attempts to meet the ubiquitous computing environment by providing a managed, extensible framework to connect various devices in a local network such as in a home, office, or automobile. By defining a standard execution environment and service interface, the OSGi promotes the dynamic discovery and collaboration of devices and services from different sources. The OSGi offers a unique opportunity for ubiquitous computing as a potential framework for achieving interoperability between various sensors, home appliances, and networked devices. The OSGi framework supports a remote installation of a bundle, which is a unit that installs and deploys services. However, in order for the service in execution to move, a specific form of bundle such a mobile service manager is needed, one which is able to move through a heterogeneous network.This paper proposes a method that can manage bundles for supporting dynamic service’s mobility between frameworks, in order to ensure the mobility of services in a multiple the OSGi framework environment. For our purposes, we have designed the mobile service management system for managing the lifecycle of the bundle and for the mobility of services in the OSGi framework. The mobile service management system we are proposing implements a bundle form which can perform in an OSGi framework as well as manage the mobile services. As a result, mobility in a ubiquitous computing environment will be supported more efficiently.

The open service gateway initiative (OSGi) framework is to provide an open environment for home services, which can be deployed by different service providers. However, currently there is no total solution for the OSGi framework to diagnose and recover from unexpected faults, especially those generated by resource conflicts between services, which would require user intervention. This paper summarizes the requirements for diagnosis in the open service platform and proposes an integrated approach to detect service conflict faults, handle general exceptions, and diagnose service errors on OSGi platforms. By providing user friendly diagnosis messages, and suggestions to fix exceptions, users can operate home gateways without a heavy learning burden, and service providers can reduce the overhead associated with user requests for technical support. The implementation is packaged as a service bundle running on the service layer of the OSGi platform. This is the first attempt to diagnose and handle the service conflicts on the OSGi platform during runtime.

It is a key problem for a 7*24 running system to update and maintain online. According to the feature of OSGi (Open Service Gateway Initiative) framework, current service dynamic update policies for OSGi framework are analyzed. In order to solve the problem of service mutual consistency and service state consistency during service update, the service dynamic update policy based on publish & subscribe model is presented. This policy is based on quiescent state theory to ensure mutual consistency when services are updated online. The process of the dynamic service update policy is described by Petri net. We realize the policy using Event Admin Service in the experiment with well-defined program model. The result shows that the policy is validate and feasibility.

Abstruct- This paper addresses the design and implementation of Session Initiation Protocol (SIP) server components required for providing Internet telephony services. We first describe a family of SIP servers necessary for Internet telephony, and discuss overall functionality for each SIP server, Then we present our implementations of SIP servers including proxy server and registrar server, along with details of processing routines. We also discuss possible organization of SIP server components for providing Internet telephony services. We will also mention about our experiences on interoperability tests with other products.

The Session Initiation Protocol (SIP) has gained momentum and is being widely used both in the Internet and Next Generation Telecommunications network as the core signaling protocol. SIP operation relies on SIP servers which are responsible for forwarding of SIP messages. It has been shown that the performance of SIP servers is largely degraded during overload conditions due to the built in message retransmission mechanism of SIP. This is an obstacle in wide deployment of SIP for a realistic situation. In this paper we propose a distributed and adaptive window based overload control algorithm, which controls the amount of calls that are forwarded to a downstream SIP server in an attempt to prevent it from being overloaded. Our scheme uses the call establishment delay as a measure of the amount of load on the downstream server and unlike other methods does not rely on explicit feedback. Using simulations we show that our proposed method performs better than a commonly used overload control algorithm and exhibits fast convergence and is stable.

Selective parsing to enhance SIP performance

현재 여러 종류의 홈 네트워크(home network) 기술들이 존재하고 있으며, 단일화된 홈 컴퓨팅(home computing) 환경을 위해서는 서로 다른 네트워크 프로토콜간의 연동이 필수적이다. 이를 위하여 여러 종류의 홈 네트워크 미들웨어(home network middleware)가 개발되었고 특히 OSGi (Open Service Gateway Initiative)는 다양한 미들웨어 환경 사이의 서비스 상호연동을 제공하기 위해 제안되었다. 그러나 OSGi의 실행환경인 프레임워크(framework)는 수동적으로 서비스 번들(service bundle), 사용자 및 장치 관리 등을 수행하는 취약점을 가지고 있다. 본 논문에서는 사용자들의 편의성을 위해 수동적으로 관리되는 부분들의 문제점을 개선하고자 한다. 이를 위하여 자동화 서비스와 효율적인 서비스 번들의 관리를 위한 SBM (Service Bundle Manager)의 구조를 제안하고, SBM을 구현하여 SBM의 실효성을 검증하였다. Since different kinds of home network technologies coexist, seamless connections between different kinds of network protocols are essential for home computing environments. Several kinds of home network middleware have been developed and OSGi(Open Service Gateway Initiative) was initiated mainly for interoperability support with service distribution between various middleware environments. Framework, OSGi service platform, has weaknesses of passive service bundle management, user management and device management. Therefore, this paper resolves passive management parts which are critical weaknesses of OSGi Specification Version 3 and proposes SBM (Service Bundle Manager) to effiently manage various service bundles. Additionally, we verify practical effects of SBM through experiments.

With the rapid development of mobile devices and Internet services, managing home security with these devices and services is gaining popularity. To expand the range of usability of conventional home surveillance cameras, we propose the UPnP-based Surveillance Camera System (USCS), which employs UPnP technology to search, control, and manage IP-based cameras. With UPnP, interconnected equipment and the control network inside the home can be accessed for data sharing, communication, and entertainment. However, the current UPnP was originally designed for local networks. Therefore, we integrated the UPnP control module into the Open Service Gateway Initiative (OSGi) framework to access UPnP services from a remote network. The control point is an external network that can access the UPnP device, which is hosted in a home area network via USCS. Our system showed improved searching, management, discovery, and manipulation of IP-based cameras in a home network using our system, compared to a conventional system. Users can use a mobile device to monitor the home security status in real time by a remote access function provided by OSGi. Hence, users can monitor their homes more efficiently and instantly, ensuring the safety of house members and the property.

This paper presents the first attempt to design an interoperability platform by integrating an RDF based information sharing infrastructure named Smart-M3 within the OSGi framework, enhancing the information level interoperability of the former with the service level interoperability of the latter. Such an interoperability platform provides a generic and simple solution to develop Smart Environment Applications.

Recently P2P-SIP (Peer-to-Peer Session Initiation Protocol) has been proposed to improve the scalability and reliability of the traditional SIP (Session Initiation Protocol) networks. However, P2P-SIP makes SIP service unreliable because large-scale P2P-SIP networks are probably more dynamic than traditional SIP networks and the service nodes are very likely to fail or leave the P2P-SIP networks. To deal with this issue, we propose a novel and lightweight algorithm, which replicates SIP transactions information among the nodes in P2P-SIP networks and selects one of the successors of the failed or departed node as the takeover server. Moreover, to reduce the retrieving delay of SIP transactions replicas, we optimize our algorithm by storing these replicas directly in the successors of the failed or departed node. The simulation results demonstrate that our algorithm maintains 99% dialogs correctly in the presence of nodes failure with acceptable overheads over the Internet.

To start voice, image, instant messaging, and generally multimedia communication, session communication must begin between two participants. SIP (session initiation protocol) that is an application layer control induces management and terminates this kind of sessions. As far as the independence of SIP from transport layer protocols is concerned, SIP messages can be transferred on a variety of transport layer protocols including TCP or UDP. Mechanism of Retransmission that is embedded in SIP could compensate for the missing packet loss, in case of need. This mechanism is applied when SIP messages are transmitted on an unreliable transmission layer protocol like UDP. Also, while facing SIP proxy with overload, it could cause excessive filling of proxy queue, postpone increase of other contacts, and add to the amount of the proxy overload. In the present work, while using UDP as transport layer protocol, invite retransmission timer (T1) was appropriately regulated and SIP functionality was improved. Therefore, by proposing an adaptive timer of invite message retransmission, attempts were made to improve the time of session initiation and consequently improve the performance. Performance of the proposed SIP was implemented and evaluated by SIPP software in a real network environment and its accuracy and performance were demonstrated.

Nowadays Session Initiation Protocol (SIP) has become the most widely used signaling protocol by the vendors in the Voice over Internet Protocol (VoIP) communication. As the SIP is gaining popularity, open architecture of VoIP often makes SIP vulnerable to so many threats. The paper introduces SIP along with its different security mechanisms with the focus on attack signatures generation technique to identify the malformed SIP messages. It aims to generate various malicious SIP messages and to verify the limitations of the existing classical Intrusion Detection System (IDS) in identifying the malicious messages. Then it sets out to implement an improved detection framework using the rules as regular expression. The experiments were carried out using SER as an open source SIP server, Kphone and X-lite as SIP clients and the SIPSAK as an attacking tool on a testbed architecture which was in a form of virtual environment created with VMware. The platforms used were BackTrack7 and Windows 7. The test was first performed on SNORT, an open source IDS and later by adding the improved detection rules in the configuration file of the SIP server. The successful attacks on the classical attack-signatures generation framework proved that the existing IDSs couldn't identify logical errors in the malicious SIP messages. The proposed detection module identified and rejected all kind of malicious SIP messages with acceptable processing overheads. Moreover the associated signatures database can also be incorporated into other VoIP protocols and open source IDSs like SNORT. This paper has provided the effective mechanism in creating well-formed defense against malicious SIP message attacks to ensure the integrity and security of VoIP subsystems.

Funding Information: V. CONCLUSIONS This work proposed four classification models based on LSTM RNNs to classify SIP dialogs. The detection probability was evaluated based on experimental data. To detect abnormal SIP dialogs, we have adopted classification features computed from the output of the LSTM RNN model and two different classification schemes were proposed. A semi-supervised scheme is shown to reach higher performance, achieving a detection probability of 99.45%, thus confirming the effective utility of the proposed methodology to detect abnormal SIP sequences in a short period of time. ACKNOWLEDGEMENTS This work was funded by Fundac¸ão para a Ciência e Tecnologia, under the projects InfoCent-IoT (PTDC/EEI-TEL/30433/2017), CoSHARE (PTDC/EEI-TEL/30709/2017), and RFSense (UIDB/50008/2020).

Since different kinds of home network technologies coexist, seamless connections between different kinds of network protocols are essential for home computing environments. Several kinds of home network middleware have been developed and OSGi (Open Service Gateway Initiative) was initiated mainly for interoperability support with service distribution between various middleware environments. In this paper, we analyze the weaknesses in the OSGi service platform, such as a non-distributed framework, passive user management, device management, and service bundle management. Moreover, we propose SBM (Service Bundle Manager) to efficiently manage various service bundles. This paper concludes with the implementation results for SBM.

Overload occurs in Session Initiation Protocol (SIP) networks when SIP servers have insufficient resources to handle all the SIP messages they receive. Even though the SIP protocol provides a limited overload control mechanism through its 503 (Service Unavailable) response code, SIP servers are still vulnerable to overload. This document defines the behavior of SIP servers involved in overload control and also specifies a loss-based overload scheme for SIP.