PROBLEM TO BE SOLVED: To provide a radio communication method, a radio base station, and a radio communication system, capable of reducing signaling and resource consumption for use for the calculation of base station clustering, by selecting optimal base station clustering according to a communication state between a terminal and each base station.SOLUTION: In the radio communication method of the present invention, a first base station communicating with the terminal transmits a request message for consulting cooperative transmission to a second base station that communicates with the terminal in cooperation with the first base station. On the basis of the received request message, the second base station transmits response signaling to the first base station.

The demand for high-quality video has been posing remarkable new challenges on achieving efficiency and fair utilization of network resources. High-quality IPTV and VoD has high-bandwidth requirements. Another trend is the popularity of p2p systems and it could severely strain broadband networks. In particular, without the ability to explicitly communicate with network providers, P2P applications mainly depend on inefficient network inference and network- oblivious peering, leading to potential inefficiencies for both P2P applications and network providers. In this paper, we propose a multi-domain resource management for super high-definition video delivery service which can effectively reduce the backbone network traffic. The Resource scheduling mechanism is discussed. The reduction of network traffic is measured.

This paper has proposed a user-oriented seamless service handoff scheme in ubiquitous computing environment. In this scenario, users can maintain their access to their personalized service uninterrupted even while moving or changing terminals. As the combination of optical fiber based technology and wireless technology, hybrid Wireless-Optical Broadband Access Network (WOBAN), can provide ubiquitous broadband access. With the development of Internet of Things (IoT) technologies, Location-Based Services (LBS) have emerged in many fields. And wireless sensors have become considerably popular with ubiquitous computing and have provided a sound solution for location-aware system. A platform is constructed to evaluate the effectiveness of the proposed service handoff scheme. Test results show that our platform is able to provide precise user positioning information and seamless service handoff with low handoff delay.

Disclosed are a communication control device, a communication control method and the system thereof, which provide efficient multi-base station joint services in a mobile communication system using dynamic clustering. Optimal base station clustering is chosen according to the communication state between a terminal and each base station, and the signaling and resources cost for calculating a base station clustering is reduced. The communication control device connects with multiple base stations through a network, and clusters the multiple base stations dynamically so that the clustered multiple base stations can provide services for the mobile terminal in union. The communication control device comprises: an interface, connecting with multiple base stations, receiving channel state information (1512) related to the mobile terminal from each base station; a memory unit, storing the channel state information (1512) of the mobile terminal received from the interface; a control unit, clustering each base station dynamically according to the channel state information (1512) of the mobile terminal stored in the memory unit.

IKEv2/IPsec has been widely deployed, such as in VPN and MIPv6, to support mutual authentication, access control and traffic protection in internet. IKEv2/IPsec gateways may maintain huge number of IKEv2/IPsec security associations. If gateway encounters failure or over-load, it will take a long time to re-establish security associations in another IKEv2/IPsec gateway. The major reason is that regular procedure of IKEv2 incurs long delay because of multiple signalling exchanges and complex computation especially in Diffie-Hellman exchange. In this paper, a new IKE SA re-establishment solution is proposed to reduce the overhead of computation and signalling by directly transferring IKE SA from old gateway to new gateway via independent IKE SA storage (stub bank). The most expensive Diffie-Hellman exchange and some of signalling can be avoided. Therefore, a huge amount of IKE/IPsec security associations can be re-established in a short time. The applicability of this solution in mobile network is further analyzed as well.

With the rapid development of wide variety of wireless technologies, it is envisioned that the future network will be a convergence of various wireless access technologies providing users with the best anywhere, anytime connections to the Internet. In such environment, it is a critical problem to enable a mobile node to intelligently select wireless access networks and achieve seamless handoff performance. This paper proposes a vertical handoff algorithm which enables a mobile node to intelligently select wireless access network among multiple access technologies, synthetically considering network characteristics and status, such as access bandwidth, response time, data loss, network congestion status, etc, along with access cost and received signal strength (RSS). With the proposed algorithm, wireless network utilization can be optimized according to user's strategy and network conditions, and real-time applications can be maintained without packet loss during handoff process. A prototype system is implemented and experimental results are analyzed.

It will take a long time to do security association syncronization among IKE/IPsec gateways possibly maintaining huge numbers of IKEv2/ IPsec SAs. The major reason is that the prcocedure of IKEv2 SA re- establishment will incur a time-consuming computation especially in the Diffie-Hellman exchange. In this draft, a new IKE security associations synchronization solution is proposed to reduce the computation by directly transferring the indexed IKE SA from old gateway to new gateway, wherein the most expensive Diffie-Hellman calculation can be avoided. Without some time-consuming IKEv2 exchanges, the huge amount of IKE/IPsec SA synchronization procedures can be finished in a short time.

Previous Probe Gap Model (PGM) based available bandwidth (AB) estimation methods all request the "busy assumption" that probing packet pairs should be in the same busy period when transmitted on bottleneck link, which is hard to satisfy especially for the low utilization path. In this paper, we first present a new probabilistic methodology to estimate AB under "non busy assumption". The methodology is quite accurate on the low utilization network path. Secondly, we propose a metric to weigh the busyness of a network path based on the distribution of output probe gap. Using the metric, we combine our new methodology and previous methodology, and present a new AB estimation method called Adaptive Available Bandwidth Estimation (A_ABE) which is fit for both low utilization and high utilization paths. We use NS-2 simulation and reproduce traffic from real Internet links to evaluate A_ABE. Compared with previous methods, A_ABE shows its advantages in terms of accuracy, overhead, and also the robustness when confronted with non-persistent cross traffic in multiple hop situations.

SIP-based multi-party conference service (MFCS) of IETF is adopted by 3GPP2 as conferencing solution. In MFCS, the service content received by multiple participants is the same. So, it is better to use multicast to support MFCS in 3G network, where air resources are limited. In 3GPP2, broadcast multicast service (BCMCS) is standardized allowing optimization of air resources for delivery of uniform content to multiple access terminals in CDMA2000 communication system. In this paper, a new solution is proposed, wherein service mapping is set up between BCMCS and MPCS in CDMA2000 network. By utilizing BCMCS, the radio and access network's resources of the CDMA systems could be saved for MPCS.

This paper proposes a mechanism to secure the mobile IPv6 networks by integrating identity based cryptosystem with cryptographically generated address. Based on an in-depth analysis of attacks and countermeasures in the CGA-based protocols, this paper gives an analysis of the so called "unauthentic key attacks", and presents a mechanism to solve this problem by integrating an IBC scheme called Combined Public Key (CPK) with CGA. Both the deployment considerations and performance analysis of this IBC-CGA scheme are present in the paper.

Recently, the interworking of 3G and 802.11 wireless data networks has become a very hot topic. These two kinds of networks have relatively mutual complementary features. The seamless integration of these two networks can surely improve the service availability and flexibility if the end users could do roaming across heterogeneous networks with simple multiple-interface terminals. In this paper, our solution of 3G/802.11integration is expatiated in detail. The solution includes four main nodes: a smart home agent, an 802.11 gateway called PDIF, a 3G gateway called PDSN and a multiple-interface terminal without mobile IP stack. The mobility scheduling module inside the home agent could do the packets scheduling and mobility notification in accord with the handover situations and local policies. The enhanced Mobile IP stack in PDIF and PDSN could work in proxy mode, which could provide mobility support for mobile terminals without mobile IP stack. The detailed description is made on home agent, PDIF, PDSN and mobile terminals. We also present the system performance testing result.

SIP-based multi-party conference service (MPCS) of IETF is adopted by 3GPP2 as conferencing solution. In MPCS, the service content received by multiple participants is the same. So, it is better to use multicast to support MPCS in 3G network, where air resources are limited. In 3GPP2, broadcast multicast service (BCMCS) is standardized allowing optimization of air resources for delivery of uniform content to multiple access ten-ninals in CDMA2000 communication system. In this paper, a new solution is proposed, wherein service mapping is set up between BCMCS and MPCS in CDMA2000 network. By utilizing BCMCS, the radio and access network's resources of the CDMA systems could be saved for MPCS.

RSVP is basically designed for fixed networks and does not provide mobility support. In order to provide QoS support for mobility in a wireless environment, we present a new resource reservation protocol for seamless handover. HO-RSVP integrates with Mobile IPv4 to maintain a continuous QoS guarantee between two mobile nodes. In the protocol, the resource reservation remains unaffected in the unchanged segments of the signal path in case of mobility. It is only necessary to make a new reservation in the changed segments. The protocol can also prevent the mobile node from moving to a performance-degraded access network through resource pre-reservation before handover. When the receiver is mobile, resource reservation can be refreshed in the data path for the sender after handover. When the sender is mobile, a procedure is initiated to tear down the old reservation after handover