Home Gateway Research Articles

Architecture of home gateway for device collaboration in extended home space

Extended home space refers not only to home appliances but also to logical space, including a wide range of out-home personal devices such as mobile phones, PDAs, laptops, car navigators, and office PCs. Seamless networking and collaboration among these devices is essential to provide users with a ubiquitous home environment in which they can use home services whenever and wherever they want to. In reality, however, there are certain barriers to this, such as the dynamic IP address, NAT, and heterogeneous service protocols. In this paper, we propose a Home Gateway that provides unrestricted collaboration between personal devices in the extended home space by overcoming these barriers with P2P networking technology.

안정적인 서비스를 위한 홈 게이트웨이 기반의 분산 컨텐츠 전송 네트워크

분산 컨텐츠 전송 네트워크(DCDN : Distributed Contents Delivery Network)란 CDN(Contents Delivery Network)에서 발전한 개념으로 컨텐츠 전송시에 사용자의 컴퓨터를 이용함으로써 낮은 비용으로 높은 확장성 및 빠른 전송을 제공하는 P2P 방식의 기술이다. 이러한 기존의 DCDN은 2가지 문제를 가진다. 하나는 사용자가 자신의 컴퓨터를 사용하는 시간이 일정하지 않고 또한 사용시간대가 특정 시간대에 집중되는 경향이 있어 안정적인 서비스를 할 수 없다는 것이고, 나머지 하나는 가정 내 NAT(Network Address Translation) 및 방화벽이 존재하면 해당 컴퓨터를 DCDN에서 사용할 수 없다는 것이다. 이에 본 논문에서는 안정적인 서비스를 위해 홈 게이트웨이 기반의 DCDN를 제안한다. DCDN을 구성할 때 사용자 컴퓨터 대신에 홈 게이트웨이를 사용하게 되면 기존 DCDN의 문제를 해결할 수 있다. 즉, 홈 게이트웨이는 24시간 사용되어 안정적인 서비스를 제공하며, NAT 및 방화벽로부터 독립적인 특성을 가진다. 제안된 방법은 유무선 공유기인 ASUS WL-500GP를 이용하여 구현하였으며, 실험을 통해 제안된 방법이 기존 방법에 비해 DCDN 구성에 있어 효율적임을 확인하였다. DCDN(Distributed Contents Delivery Network) as known the next generation of CDN is to exploit the resource of client PCs based on P2P technology to provide low cost, high scalability and high speed services when contents are delivered. This DCDN has two problems. One is that DCDN can't provide a sustainable service because client PCs are on/off irregularly and their on times tend to focus on specific time zone, and the other is that client PCs can not be accessed outside in DCDN if they are behind NAT or Firewall. In this paper, we present a distributed contents delivery network based on home gateway for a sustainable service. If home gateway is used in DCDN instead of client PC, it can solve the two existing problems of DCDN. That is, home gateway can provide a sustainable service because it is on during all day and it is not behind NAT and Firewall. The proposed method is implemented with ASUS WL-500GP, a wired/wireless router. Experimental results show the effectiveness of the proposed method compared to the existing method of DCDN.

A novel memory management scheme for residential gateways

Home gateways must manage services despite limited memory resources. In home gateway models (e.g., OSGi), services are implemented as software bundles (or plug-ins) that can be downloaded from the Internet and executed in the gateway. Services, in gateways, are not independent; they collaborate and complement each other. The problem we are solving is as follow: when the gateway runs out of memory, which service(s) will be stopped or kicked out of memory to start a new service? The problem was initially inspired by the FTTH (Fibre To The Home) trail project in Japan with NTT because of the limited memory in Panasonic set-top-box IP-STB. Note that stopping a given service means that all the services that depend on it will be stopped too. Because of the service dependencies, traditional memory management techniques, such as best fit, first fit, or worst fit, are not suitable. Our goal is to minimize the total number of stopped services while fulfilling the request of the new service. In this paper, we present two algorithms for service replacement and memory management in home gateways. The algorithms take into consideration the dependencies between different services, in addition to the amount of memory occupied by each service. The first one achieves optimal solution in O(n 2) time and O(nh) space, using dynamic programming. However, the optimal solution requires substantial memory and CPU resources. Then we propose a heuristic that compute solutions very close to the optimal but with much less time and space requirements. We carry simulation experiments to evaluate the effectiveness of the proposed techniques and compare them with traditional memory management techniques.

Home gateway operating model using reference monitor for enhanced user comfort and privacy

In home network environments, user comfort and privacy are key prerequisites for customer satisfaction and data security. Although methods such as ACLs and others control the user-access for home network devices, most existing methods have yet to satisfactorily address the issues related to a user's comfort level and his or her protection of privacy. Therefore, this paper outlines the proposal for home gateway operating model using reference monitor in an OSGi service platform, whose goal is to enhance the operation required to efficiently meet a user's access, convenience, and privacy concerns. The reference monitor is a collection of access controls for objects, and is also capable of providing the facilities for access control. Furthermore, it adds the element of comfort to user access control, because it is intended as a core part of how subjects interact with objects. The proposed model is based on an RBAC model to effectively manage access control. Its policy is classified into two types (e.g., user-role assignment policy and permission-role assignment policy) in an attempt to not only better protect user privacy, but also to improve the performance of the policy operation. It is argued that the new home gateway model provides sufficient and effective guidelines to suggest future access control policies.

An autonomic approach to offer services in OSGi-based home gateways

The home IT environment is one the most promising areas for telecom operators. Nowadays, home area networks (HAN) are composed of a variety of heterogeneous devices, such as computers, webcams, sensors, set-top-boxes, etc. A key element in a HAN is the home gateway: a device managing the different networks in the home environment. But the management of this environment is a complex task, with an increasing number of heterogeneous devices interconnected. This paper proposes the application of the “autonomic communications” paradigm to this problem. Under this paradigm, each device has the intelligence for accomplishing the self-* functionalities: self-configuration, self-optimization, self-healing and self-protection. This paper describes a proof of concept of an autonomic communications architecture to solve the self-configuration problem. Using a home gateway, with the OSGi framework deployed, an autonomic element has been developed with the goal of finding and personalizing the service offer for a specific user. The autonomic element is context aware, as it senses devices connected to the home network together with user preferences. The services and profiles are modeled with an ontology in OWL, as well as reasoning rules in SWRL which are used by the autonomic element for inferring useful services and proposing a personalized service offer for each customer. The autonomic element has been implemented as an OSGi application and its performance has been evaluated providing successful results.

NAT Traversing Solutions for SIP Applications

Session Initiation Protocol (SIP) has been proposed for multimedia services and wide-area connectivity in smart home environments (SHEs). An important issue for SIP deployment in SHEs is network address translator (NAT) traversing. SIP and Real-time Transport Protocol (RTP) packets are delivered between an SHE (i.e., private IP network) and Internet (i.e., a public IP network) through an NAT function of a home gateway, and the NAT translates the IP/transport layer address and port number but leaves the application layer content unchanged. This results in inconsistency between the IP addresses/port numbers in the IP/transport layers and those in the SIP layer. To resolve this issue, we describe six solutions including static route, UPnP, STUN, ICE, ALG, and SBC. Then we compare these solutions in terms of smart home appliance (SHA) modification, scope of NATs supported, multilayer NAT traversal, ease of configuration, security issue, and time complexities.

ECHOS

In this paper we propose a radical solution to data hosting and delivery for the Internet of the future. The current data delivery architecture is "network centric", with content stored in data centers connected directly to Internet backbones. This approach has multiple drawbacks among which complexity of deploying data centers, power consumption, and lack of scalability are the most critical. We propose a totally innovative and orthogonal approach to traditional data centers, through what we call "nano" data centers, which are deployed in boxes at the edge of the network (e.g., in home gateways, set-top-boxes, etc.) and accessed using a new peer-to-peer communication infrastructure. Unlike traditional peer-to-peer clients, however, our nano data centers operate under a common management authority, e.g., the ISP who installs and maintains the set-top-boxes, and can thus cooperate more effectively and achieve a higher aggregate performance. Nano data centers are, therefore, better suited for providing guaranteed quality to new emerging applications such as online gaming, interactive IPTV and VoD, and user generated content

An Approach for Content Sharing among UPnP Devices in Different Home Networks

An approach for content sharing among UPnP devices in different home networks is proposed. In this approach, a "SHARE" module is designed that extends the HG (home gateway) with an UPnP-compatible protocol. By using SSDP (simple service discovery protocol) messages used in the UPnP device architecture, the SHARE module provides the connectivity that is needed to control other UPnP devices for content sharing. For transparent content sharing, the SHARE utilizes the class hierarchy of the UPnP AV architecture. It also works to support a distributed streaming service that can be adopted by UPnP AV architecture as a content sharing method. Through design-level verifications and a partial implementation of the proposed SHARE module, the feasibility of the approach is validated.

Multiservice home gateways: business model, execution environment, management infrastructure

The home gateway market is undergoing deep changes. On one side, home networks are evolving, getting dynamic and federating more and more devices. On the WAN side, new actors appear, such as multimedia content providers. From both sides emerge new features and new management needs. In this article we highlight challenges and benefits of moving more intelligence to the home gateway, making it more than a simple interconnection device. We argue that we need a full-fledged execution environment on gateways to address the evolution of business models. We present this evolution and summarize existing solutions for execution environments and management for home gateways. Then we propose two improvements that reflect the new requirements. The first improvement is a high-level virtualization of service gateways, and the second one recommends an end-to-end dynamic multiprovider management system.

A trial of telecare for supporting care to the elderly in Liverpool

A pilot telecare system was trialled in Liverpool. It was used to support the provision of care to 21 of the city council's elderly and frail social services clients. A typical installation consisted of about 20 wireless, ambient sensors in the client's home. A home gateway device ran alerting algorithms designed to learn the normal patterns of user behaviour and to identify deviations from this in real-time. When deviations were detected, social service delivery teams were alerted to a possible cause for concern. The pilot service ran for about 30 months and included a period of examination by independent evaluators. The evaluation found that overall the people who used the service – both users and carers – were overwhelmingly pleased with it and viewed it as a great success.

QoS management in heterogeneous home networks

An OSGi (Open Services Gateway Initiative) home gateway system manages the integration of heterogeneous home networks protocols and devices to develop ubiquitous applications. Wired and wireless heterogeneous home networks have different QoS concerns. For instance, jitter and latency are important concerns in web phones, while packet loss ratio is important in on-line video. This study adopts UPnP QoS specification version 1.0 to design an adaptive QoS management mechanism based on the RMD (Resource Management in DiffServ) architecture. This study monitors real-time network traffic, and adaptively controls the bandwidth, to satisfy the minimum but most important quality for each application in home network congestion. Simulation results indicate that the average jitter, latency and packet loss are reduced by 0.1391ms, 0.0066s, and 5.43%, respectively. The packet loss ratio is reduced by 4.53%, and the throughput is increased by 1.2% in high definition video stream; the packet loss ratio is reduced by 1.89% for standard definition video stream, and in VoIP (Voice over IP) the jitter and latency are reduced to 0.0407ms and 0.0209s, respectively.

Implementation of the DLNA Proxy System for Sharing Home Media Contents

The paper proposes a methodology to provide services for accessing and sharing various media contents securely, those are distributed over consumer electronics (CEs) in the home network. To do so, we propose the DLNA proxy system (DPS) architecture which helps to gather various media information available from the distributed AV devices in the home and to share the media contents across the public IP network via established secure channels. The proxy system is implemented on the home server which acts as media server and the hardware accelerated IP security (IPSec) virtual private network (VPN) is configured on the home gateway which establishes and maintains secure connections between the home and public networks.

Design of a SIP-based real-time visitor communication and door control architecture using a home gateway

Though typical video door phone systems can be used to talk to the visitors at the door, they have some shortcomings: the resident should stay in house and he/she is not informed of any visitor information on his/her return to home. To overcome these limitations, we propose an architecture supporting user mobility, with which the resident at anywhere can view and converse with a visitor at the front door using PCs, PDA's and home servers with Internet connections. We implemented the proposed architecture using SIP (session initiation protocol) and a home gateway system connected to a conventional intercom or a video door phone system.

Integration of Web Services with Mobile Home Automation

This study develops the web services that are applied in home automation via the Internet and operated by mobile portable devices. Related work, a service-oriented architecture (SOA) platform is developed. Mobile portable devices are acting as Service-Requestor. A home appliance server is acting as Service-Provider. We use Web Services Description Language (WSDL) to describe their binding. The Simple Object Access Protocol (SOAP) provides a simple and lightweight protocol for communicating between them. An example is described in this study that includes a General Packet Radio Service (GPRS) control platform to provide the home gateway function.

FORMAL VERIFICATION OF BUNDLE AUTHENTICATION MECHANISM IN OSGi SERVICE PLATFORM: BAN LOGIC

Security is critical in a home gateway environment. Robust secure mechanisms must be put in place for protecting information transferred through a central location. In considering characteristics for the home gateway environment, this paper proposes a bundle authentication mechanism. We designed the exchange mechanism for transferring a shared secret key. This transports a service bundle safely in the bootstrapping step, by recognizing and initializing various components. In this paper, we propose a bundle authentication mechanism based on a MAC that uses a shared secret key created in the bootstrapping step. In addition, we verify the safety of the key exchange mechanism and bundle authentication mechanism using BAN Logic. From the verified result, we achieved goals of authentication. That is, the operator can trust the bundle provided by the service provider. The user who uses the service gateway can also express trust and use the bundle provided by the operator.

An implementation of FTTH based home gateway supporting various services

Home gateway (HG), or called residential gateway (RG), is a device that connects an access network, WAN (wide area network), to a home network (private network, generally). FTTH (fiber to the home) based HG is an HG with FTTH network as an access network interface. In this paper, we propose an implementation of FTTH based HG, specially EPON (Ethernet passive optical network) based HG. With the FTTH access network interface, the proposed HG can provide service bandwidth of 100 Mbps to 1 Gbps to each subscriber. The network bandwidth is enough to provide various home network services for each one. We propose the novel home gateway's architecture to provide various services efficiently and show its implementation. The use of VLAN (virtual local area network) scheme to isolate two network domains, WAN of public network and LAN of private home network, within single L2 Ethernet switch and the direct packet forwarding scheme without L3 processing for some specific packet are key idea for the HG supporting various services proposed in this paper. To manage the direct forwarding table, we use the information acquired from IGMP snooping function of the L2 Ethernet switch.

Efficient video transcoding technique for QoS-based home gateway service

The home gateway integrates heterogeneous home network environments and interconnects the home network and the public access networks. It is natural that users want to see the visual contents on the home network from outside the home. However, there exist significant differences in network capability and computing power of users. Video transcoding technique is an efficient mechanism to deliver visual contents to a variety of users who have different network conditions or terminal devices with different display capabilities. In this paper, we propose an efficient video transcoding technique as the key component of the home gateway architecture. It consists of two types of transcoding methods for adapting the bitrate of streaming video to the bandwidth of the transmission channel; spatial resolution reduction transcoding and temporal resolution reduction transcoding. The two transcoding methods are alternatively or simultaneously operated according to the requirements of users. Experimental results show that the proposed transcoding methods can preserve image quality while transcoding to the low bitrate.

Residential HDTV distribution system using UWB and IEEE 1394

We propose a residential HDTV distribution system that is composed of UWB and IEEE 1394. This system converts multi-channel MPEG TS broadcasting data into IEEE 1394 packets or UWB packets based on IEEE802.15.3 WPAN. Any distributed UWB packets are again converted into MPEG TS data through a UWB-to-IEEE1394 bridge. Moreover, this system can also transmit IPTV packets encapsulated with IEEE 1394 packets from a home gateway or home server to a home UWB network. We implement UWB MAC and physical layer chips using CMOSASICs.

라이브 비디오 스트리밍을 지원하는 RTC 기반 홈 게이트웨이의 설계 및 구현

본 논문은 흠 내부의 Non-SIP 기반 비디오 카메라로부터 홈 외부의 SIP 기반 단말기로 비디오 스트림을 전송할 수 있는 흠 게이트웨이의 설계 구현에 목적이 있다. 홈 게이트웨이는 OSGi 프레임워크를 기반으로 하였으며 흠 내부의 기기로부터 흠 외부의 이동 중인 모바일 사용자를 연결하기 위해 SIP 스택을 내포하는 마이크로소프트 사의 RTC 기술을 이용하였다. 홈 게이트웨이 상에, SIP 세션의 연결 등을 관리하는 RTC 번들을 개발하였으며, 홈 내부의 Non-SIP 기반 비디오 카메라로부터 비디오 스트림을 읽기 위해 가상 비디오 캡쳐 드라이버를 개발하였다. 최종적으로 설계 구현된 홈 게이트웨이를 테스트하기 위해 SIP 프로토콜을 탑재한 윈도우 메신저를 흠 외부의 단말기로 설정하고 AXIS 2100 UPnP 비디오 카메라를 홈 네트워크에 연결하여 비디오 카메라로부터 이동중인 윈도우 메신저로의 세션 연결과 라이브 비디오의 스트리밍을 실험하고 확인하였다. The objective of this paper lies in the design and implementation of a home gateway supporting live video streaming which flows from the Non-SIP video camera in home to the mobile SIP device outside. We developed the home gateway on the OSGi framework and employed the RTC technology which embeds an SIP stack so that the multimedia session can be established from the home device to the mobile user outside. And also we developed an RTC bundle to manage the session and a virtual capture device driver to read the video stream from the Non-SIP video camera in the home network, and installed them on the home gateway. Finally, we constructed the experimental environment that has the windows messenger as the SIP mobile device and an AXIS 2100 UPnP video camera as a video source, and then tested if the session establishment to the mobile user from the camera and live video streaming work well between them.

Convergence of broadcasting and communication in home network using an EPON-based home gateway and overlay

Home network systems including a home gateway are expected to facilitate the convergence of broadcasting and communication services to complement the ubiquitous computing and services. We focus on supporting the convergence of broadcasting and communication in home network systems with an Ethernet passive optical network (EPON)-based home gateway. We propose a new architecture that integrates broadcasting and data services in a home network. For this architecture, we use an overlay transport mechanism in access network and IP multicast techniques of the Internet group management protocol (IGMP) and IGMP snooping in a home network. We also detail a set of mechanisms and procedures for a home broadcasting service through the home gateway system. Our new scheme is composed of three parts: a) an overlay transmission model of video broadcasting signals (satellite and/or cable TV) and Internet data, b) to select a specific video broadcasting channel and video broadcasting stream into IP multicast packets in tuner/conversion module using multiple tuner system and c) to transfer the converted IP multicast packets to L2 switch of home gateway's core module and to send them out to target port(s) by L2 multicast using IGMP snooping.