Control and Provisioning of Wireless Access Points (CAPWAP) is a protocol for encapsulating a station's data frames between the Wireless Transmission Point (WTP) and Access Controller (AC). Specifically, the station's IEEE 802.11 data frames can be either locally bridged or tunneled to the AC. When tunneled, a CAPWAP Data Channel is used for tunneling. In many deployments, encapsulating data frames to an entity other than the AC (for example, to an Access Router (AR)) is desirable. Furthermore, it may also be desirable to use different tunnel encapsulation modes between the WTP and the Access Router. This document defines an extension to the CAPWAP protocol that supports this capability and refers to it as alternate tunnel encapsulation. The alternate tunnel encapsulation allows 1) the WTP to tunnel non-management data frames to an endpoint different from the AC and 2) the WTP to tunnel using one of many known encapsulation types, such as IP-IP, IP-GRE, or CAPWAP. The WTP may advertise support for alternate tunnel encapsulation during the discovery and join process, and the AC may select one of the supported alternate tunnel encapsulation types while configuring the WTP.

The Control and Provisioning of Wireless Access Points (CAPWAP)protocol binding for IEEE 802.11 defines two Medium Access Control(MAC) modes for IEEE 802.11 Wireless Transmission Points (WTPs): Splitand Local MAC. In the Split MAC mode, the partitioning ofencryption/decryption functions is not clearly defined. In the SplitMAC mode description, IEEE 802.11 encryption is specified as locatedin either the Access Controller (AC) or the WTP, with no clear way forthe AC to inform the WTP of where the encryption functionality shouldbe located. This leads to interoperability issues, especially when theAC and WTP come from different vendors. To prevent interoperabilityissues, this specification defines an IEEE 802.11 MAC Profile messageelement in which each profile specifies an unambiguous division ofencryption functionality between the WTP and AC.

The mobile network core is evolving towards an unlayered and decentralised architecture, in which the current centralised mobility management mechanisms cannot be used efficiently. In this paper, a flat IP FLIP mobility management approach is proposed. It enforces IP mobility to the cellular network edge with the help of the distributed gateways. In FLIP, mobility management-related information is maintained in the distributed gateways, and multiple management domains tailored for cellular networks are considered. Autonomicity is also integrated in FLIP. Besides, FLIP supports also the ID/locator separation and the smooth transition between the upgraded mobile hosts and the traditional hosts. A prototype of FLIP has been implemented and an experimental network consisting of commercial and educational network has been established. Experimental and evaluation results show that FLIP is an efficient approach for mobility management oriented to the future mobile network architecture.

Quantitative analysis of security properties in wireless communication systems is an important issue; it helps us get a comprehensive view of security and can be used to compare the security performance of different systems. This paper analyzes the security of future wireless communication system from an information-theoretic point of view and proposes an overall security metric. We demonstrate that the proposed metric is more reasonable than some existing metrics and it is highly sensitive to some basic parameters and helpful to do fine-grained tuning of security performance.

Wireless Local Area Network (WLAN) technology has evolved very quickly in recent years. This paper introduces several new trends in the development of WLAN technology. Activities and progress in the standardization organization of WLAN, e.g. IEEE 802.11, are introduced. Next generation WLAN technology, a key enabling technology to make WLAN easy to use, together with low power and extended radio coverage are analyzed in this paper.

False data filtering schemes are designed to filter out false data injected by malicious sensors; they keep the network immune to bogus event reports. Theoretic understanding of false data filtering schemes and guidelines to further improve their designs are still lacking. This article first presents an information-theoretic model of false data filtering schemes. From the information-theoretic view, we define the scheme's filtering capacity CFi as the uncertainty-reduction ratio of the target input variable, given the output. This metric not only performs better than existing metrics but also implies that only by optimizing the false negative rate and false positive rate simultaneously, can we promote a scheme's overall performance. Based on the investigation from the modeling efforts, we propose HiFi, a hybrid authentication-based false data filtering scheme. HiFi leverages the benefits of both symmetric and asymmetric cryptography and achieves a high filtering capacity, as well as low computation and communication overhead. Performance analysis demonstrates that our proposed metric is rational and useful, and that HiFi is effective and energy efficient.

With the mobile network core evolving towards an unlayered and decentralized architecture, the traditional centralized mobility management mechanisms are becoming more and more inefficient. In this paper, an autonomic flat IP mobility management approach (A-FLIP) is proposed. It enforces the mobility management and autonomicity to the "cloud" of distributed gateways. In A-FLIP, mobility management related information is maintained in the distributed gateways at the network edge, and multiple decision elements are integrated in these gateways. Hence, autonomic behaviors like self-configuration and self-healing can be realized in the distributed mobility management systems. A prototype of A-FLIP has been implemented and an experimental network consisting of commercial and educational network has been established. Experimental results have demonstrated that A-FLIP is an efficient mechanism for mobility management oriented to the future mobile network architecture.

This document specifies a new Mobility Header message type that can be used between a home agent and mobile node to signal to a mobile node that it should acquire a new home agent.

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.

A majority of current bandwidth estimation methodologies rely on the principle of the bottleneck spacing effect. Based on the concept of packet dispersion, many packet pair/packet train techniques were presented to estimate capacity/available bandwidth. However, these methods failed for measurement on high capacity path, because they could not measure bandwidth beyond the source node's maximum sending rate. In addition, current methodologies do not consider the effect of cross traffic routing on available bandwidth estimation. This paper analyzes the effect of the routing of cross traffic packets on available bandwidth measurement in detail. Then based on Monte Carlo Method, a novel methodology fundamentally different in the basic idea from the previous methods is presented to measure end-to-end available bandwidth. This method sends small single packet randomly instead of sending packet pair/train back-to-back. It could work on network whose capacity is far beyond the maximum sending rate of the sender. Analysis and simulations show that besides end-to-end available bandwidth, this method could measure the capacity and idle ratio of targeted link, and then calculate the change of traffic flow on each node and the percentage of different cross traffic on each link.

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