Efficient hierarchical SIP mobility management for WiMAX networks

Nowadays due to the increase in demand for various multimedia services requiring high capacity, shortage of wireless resources becomes a serious problem in cellular networks. It is difficult to suddenly increase the capacity of wireless communication networks because of high cost and complexity. In order to increase the capacity of wireless communication networks with minor changes and low cost, internetworking is needed. The main objective of SIP is to support the upper layer and mobility management protocols to optimize the handover process between heterogeneous networks such as Ethernet, Bluetooth, Wi-Fi, WiMAX, 802.11 and various other networks. The basic purpose of the SIP standard is to facilitate between heterogeneous networks to provide seamless mobility. This standard also supports handover for the both mobile as well as stationary users. For mobile users, handover can occur when wireless link condition changes due to Mobile Node (MN) movement. In this proposed work, Vertical handover is implemented between WLAN and WiMAX networks by using Session initiation protocol and the performance metrics such as Network delay, Neighbour advertisements, Handover delay and throughput were obtained.

Performance analysis of Virtual Mobility Domain scheme vs. IPv6 mobility protocols

There are several non-interoperable peer-to-peer (P2P) protocols available today with different functionalities. In order to exploit this functional diversity on mobile devices, we have developed a plug-and-play application platform (PnPAP). PnPAP provides autonomous, dynamic selection between multiple P2P protocols while ensuring the best available network connectivity. In this paper, we introduce methods for utilizing session initiation protocol (SIP) in inter-PnPAP communications. This communication may include downloads of distributed P2P resources such as polymorphic protocol libraries or dynamic state-machine control modules. These components are then used to optimize connectivity management between heterogeneous wireless access networks. In addition, context information may be exchanged between mobile nodes in order to facilitate extended service availability, operability and quality. We analyze the feasibility of merged P2P and All-IP (including SIP) architecture through the novel use of a specialized SIP server and the leveraging of the emerging instant messaging capabilities of SIP. Preliminary measurement results from the prototype implementation on a Symbian platform and test-bed, with overhead and latency analysis, illustrate the feasibility of this approach.

To improve the local mobility performance of a wireless network, we present a new framework, namely Efficient Framework for Local Mobility (EFLoM). In EFLoM, we introduce three entities: Local Anchor Router (LAR), Wireless Access Gateway (WAG) and Mobile Node (MN). LAR is a router that is in charge of MN's IP mobility management. It keeps track of MN's movement, and delivers the MN's packets to its current location. AWAG is an access router that is responsible for managing the traffic flows within the same local mobility domain. In EFLoM, when Corresponding Node (CN) and MN connect to the same local mobility domain, packets are sent directly between CN and MN by WAG, without suffering sub-optimal routing problems. A MN is a mobile host which updates its data packets' header with its current location address before packets are sent out. To evaluate our new framework, we compare EFLoM with Hierarchical Mobile IPv6 Mobility Management (HMIPv6) [4] which is an existing protocol that has good performance for local mobility. Both analytical analysis and simulation result show that EFLoM can attain substantial improvements over HMIPv6 in terms of handover delay, end to end delay, traffic overhead, which therefore presents EFLoM as a new engineering alternative to existing MIPv6 based techniques.

With the evolution and penetration of the IP-based core network and the mobile access networks, more and more legacy services are being transferred to the converged and unified IP-based platform. For realizing this transfer, SIP (Session Initiation Protocol) has been adopted by standards bodies for creating, modifying, and terminating multimedia sessions. SIP with application-level mobility support can replace MIP (Mobile IP) to provide a FMC (Fixed Mobile Convergence) solution. Taking the important role of SIP into account, it is critical to fully resolve the SIP security issues including service authentication, confidentiality, and integrity protection on both signaling and data transmission. IPSec (IP Security) and the combination of TLS (Transport Layer Security) and SRTP (Secure Real-time Transport Protocol) are two typical SIP security solutions that can protect signaling and data transmission from various security attacks. However, these security solutions don't consider the issue of mobility support during the handover of mobile nodes among different access networks. This paper, therefore, proposes an effective SIP security solution that realizes SIP security with seamless mobility support across heterogeneous mobile networks. We compare the proposal to existing approaches and show that it better satisfies the SIP security requirements in terms of security, mobility support, and performance.

Web Real-Time Communication (WebRTC) introduces real-time multimedia communication as native capabilities of Web browsers. With the adoption of WebRTC the Web browsers will be able to use WebRTC to communicate with one another (peer-to-peer), and with WebSocket servers such as Mobicents SIP Servlets and other server technologies that support WebSocket communication to enable SIP-to-WebRTC communication. This paper outlines the potential of WebRTC and discusses the two common methods of doing real-time communication in Web browsers through WebRTC. The methods are JavaScript Object Notation (JSON) via XMLHttpRequest (XHR) and Session Initiation Protocol (SIP) via WebSocket. A three-user WebRTC video chat prototype application was developed and used to evaluate both methods. Additional signalling overhead introduced into a browser by each method was determined. The results showed WebRTC-SIP/WS has more overhead than WebRTC-JSON/XHR. These signalling overhead findings are useful in that they could help application developers make decision on their choice of technologies and protocols when developing WebRTC-supported applications.

A SIP-based web client for HTTP session mobility and multimedia services

The third-generation partnership project (3GPP) and 3GPP2 have standardized the IP multimedia subsystem (IMS) to provide ubiquitous and access network-independent IP-based services for next-generation networks via merging cellular networks and the Internet. The application layer Session Initiation Protocol (SIP), standardized by 3GPP and 3GPP2 for IMS, is responsible for IMS session establishment, management, and transformation. The IEEE 802.16 worldwide interoperability for microwave access (WiMax) promises to provide high data rate broadband wireless access services. In this paper, we propose two novel interworking architectures to integrate WiMax and third-generation (3G) networks. Moreover, we analyze the SIP-based IMS registration and session setup signaling delay for 3G and WiMax networks with specific reference to their interworking architectures. Finally, we explore the effects of different WiMax-3G interworking architectures on the IMS registration and session setup signaling delay.

The continuous efforts made towards efficient mobility management in next-generation wireless networks are one of the major challenges for next-generation mobile systems. To track host mobility, the IETF has developed some mobility management protocols such as Mobile IP and Proxy Mobile IPv6. These protocols set up a tunnel to forward packets to the mobile node while the user is away from its home network. The tunneling method provided by Multi-Protocol Label Switching can be profitably used to take advantage of the Multi-Protocol Label Switching traffic engineering capability to achieve fast-reroute when a mobile node changes its point of attachment to the network. Moreover, service disruption during handoffs causes excessive packet loss that needs to be minimized to support quality of service requirements of emerging applications. We present a performance evaluation and numerical results of the most representative host-based and network-based mobility management approaches. We highlight the importance of the tunneling method with special attention to those protocols that have integrated Multi-Protocol Label Switching in its access network.

The mobile IP protocol has been designed to address the problem of roaming between IP networks. However, as mobile nodes moves between networks, the signaling overhead causes significant disruption to real time data traffic. The localized mobility management (LMM) has been proposed to enhance the handoff performance between networks within the same domain. By introducing the concept of local mobility agent (LMA), a mobile node visiting a foreign domain is exempted from sending frequent address update to its home agent and correspondent nodes, when its movement is limited to the visited domain. As multiple LMAs are configured in a domain for redundancy, scalability and load sharing concerns, LMA selection becomes an issue. This paper proposed a new LMA selection algorithm, mobile controlled movement tracking (MCMT). The objective of this new algorithm is to discover the optimal LMA in terms of selection stability and load balancing, by taking into consideration the mobility characteristics of the mobile node. Our analysis shows that this proposal can provide good support for low latency handoff and load sharing among LMAs.

Wireless networks incorporate Mobile Nodes (MNs) that use wireless access networks to communicate. However, the communication among these MNs are not remained stable due to the poor network coverage during inter mobility. Moreover, the wireless nodes are typically small that results in resource-constrained. Thus, it is uphill to use algorithms having giant processing power or memory footprint. Accordingly, it is essential to check schemes consistently to evaluate the performance within the probable application scenario. To do so, numerical analysis could be a notable method to grasp the performance of mobility management schemes as well as the constraint of evolving mobility management solutions specifically for multi-interfaced MR in Proxy NEMO environment. This paper analyzes handoff performance by using a mathematical model of Multihoming-based scheme to support Mobility management in Proxy NEMO (MM-PNEMO) environment. Moreover, a comparative study has been made among the standard Network Mobility Basic Support Protocol (NEMO BSP), Proxy NEMO (PNEMO) and MM-PNEMO scheme respectively. The performance metrics estimated for these schemes are mainly handoff delay and packet loss. This paper also analysed the packet loss ratio and handoff gain as a function of cell radius, number of SMR and velocity respectively. It is apparent that, the MM-PNEMO scheme shows lower packet loss ratio (1%) compared to NEMO-BSP (11%) and P-NEMO (6%).

Two of the major challenges for next-generation mobile systems are to achieve seamless mobility management in next generation wireless networks and to manage resources efficiently given the exponential growth that mobile data traffic has experienced over the last few years. To track host mobility, the IETF has made important efforts to develop mobility management protocols such as Mobile IPv6 and Proxy Mobile IPv6. These protocols establish a tunnel to connect the mobile node with its correspondent node. The tunneling method provided by MPLS can be profitably used to take advantage of MPLS traffic engineering capabilities in order to achieve faster re-routing when a mobile node changes its point of attachment to the network. Moreover, in order to deal with increasing mobile traffic demand, mobility management network architectures are being redesigned towards a more distributed operation. Given these scenarios, service disruption during handoffs continues to cause excessive packet loss that needs minimizing in order to support quality of service requirements for emerging applications. In this paper, a qualitative and quantitative analyses of the most representative host-based and network-based mobility management approaches is presented, including recent distributed mobility management approaches.

Currently, various efforts are being performed on specifying distributed mobility management (DMM) for IPv6 mobile networks. DMM is expected to eliminate the limitations of the current IPv6 mobility protocols and to cope with the rapid increase in mobile data traffic. In current DMM approaches, the mobility anchoring is distributed at the access router level and the mobile node changes dynamically the mobility anchor for new sessions. Although such approaches avoid any network bottleneck and allow optimal routing in most cases, they lack reachability support since the mobile node has no permanent IPv6 address. In this paper, we consider one of the DMM approaches, dynamic mobility anchoring, and study the usage of session initiation protocol (SIP) for providing reachability support. After defining different SIP-based location update modes, we carry out a comparative cost analysis considering new performance metrics related to the processing loads at each network entity. We consider the location update loads on the location server as well as the context, signaling, and tunneling loads on a mobility anchor. We investigate the different modes in several scenarios, allowing the mobile network operator to adopt the preferred mode depending on their architecture.

The IP Multimedia Subsystem (IMS) in all-IP based next generation communication environment can offer network/service providers various multimedia services (e.g.,voice, audio, video and data etc). The IMS is worthy of notice in that it is possible to make wired/wireless convergence and quick service development. The IMS needs an efficient Session Initiation Protocol (SIP)-based routing among Call Session Control Functions (CSCF) in charge of call and session processing. In this paper, we propose a dynamic routing algorithm for managing CSCF agents using management system based on Fault, Configuration, Accounting, Performance and Security (FCAPS) in the IMS network.

The next generation wireless network is predicted to be a heterogeneous network of various wireless technologies such as: WiFi, WiMAX, Bluetooth, GPRS and UMTS. With these wireless technologies, the Internet users can virtually access the Internet from anywhere and with a number of option; either at home by WiFi or outdoor by WiMAX and UMTS. However, the current network architecture does not support mobile devices to roam freely across networks or in other words, does not have mobility support. A mobile device can not keep its on-going sessions continued while crossing to another network. Besides the standard Mobile IP, Terminal Mobility Support Protocol is another proposal to support application mobility using Session Initiation Protocol. Even though these proposals allow mobile nodes to roam freely across different networks, their poor handover management still poses some problems such as: long handoff delay, high packet loss, lack of QoS provisioning, no efficient support to handoffs between heterogeneous network.