Distributed Mapping Management of Identifiers and Locators in LISP-based Mobile Networks

The Locator Identifier Separation Protocol (LISP) has been proposed as an identifier-locator separation scheme for scalable Internet routing. However, LISP was originally designed in the fixed network environment rather than in the mobile network environment. In particular, the existing LISP mobility schemes are based on a centralized map server that is used as an anchor point for mobile nodes, and thus intrinsically subject to some limitations in mobile environment. In this paper, we propose a distributed mapping management of Endpoint Identifiers (EIDs) and Locators (LOCs) in mobile LISP networks. We use Routing LOC (RLOC) and Local LOC (LLOC) as locators for mobile hosts. RLOC represents the IP address of the domain gateway, and LLOC is the IP address of the access router that a host is currently attached to. For EID-LOC mapping management, each network domain has a Distributed Map Server (DMS) over its gateway. Each DMS keeps track of the EID-LOC mapping information for mobile hosts in the distributed way. The proposed scheme is also a network-based approach, in which each access router, instead of a host, performs the mapping management operations. From the performance analysis, we can see that the proposed distributed scheme can give better performance than the existing schemes in terms of the signaling delays required for EID-LOC mapping update and query operations.     

A distributed mobility control scheme in LISP networks

The locator identifier separation protocol (LISP) has been made as an identifier-locator separation scheme for scalable Internet routing. However, the LISP was originally designed for fixed network environment, rather than for mobile network environment. In particular, the existing LISP mobility control schemes use a centralized map server to process all the control traffics, and thus they are intrinsically subject to some limitations in mobile environment, such as large overhead of mapping control traffics at central map server and degradation of handover performance. To overcome these problems, we propose a distributed mobility control scheme in LISP networks. In the proposed scheme, we assume that a mobile host has a hierarchical endpoint identifier which contains the information of its home network domain. Each domain has a distributed map server (DMS) for distributed mapping management of Endpoint Identifiers (EIDs) and Locators (LOCs). For roaming support, each DMS maintains a home EID register and a visiting EID register which are used to keep the EID-LOC mappings for mobile hosts in the distributed manner. For performance analysis, we compare the control traffic overhead (CTO) at map servers, the signaling delay required for EID-LOC mapping management, and the handover delay for the existing and proposed schemes. From numerical results, it is shown that the proposed distributed scheme can give better performance than the existing centralized schemes in terms of CTO, total signaling delay for EID-LOC mapping management, and handover delay.     

Using DHCP with computers that move

The Dynamic Host Configuration Protocol (DHCP) was designed to allow the frequent allocation of resources and configuration information useful to Internet hosts at boot time, including Internet addresses in particular. It turns out that getting a new Internet address is crucial to the problem of enabling the movement of Internet hosts from one network to another, and thus DHCP is quite relevant to the problem of providing seamless, transparent mobility to Internet hosts. We decided to investigate the ways that DHCP could be of assistance in this regard. Since the DHCP protocol was not itself designed for the purpose of providing host mobility, a number of problems arise. Our experience with deploying DHCP, and our proposed mechanisms for the use of DHCP with mobile computers, are the subjects of this paper.     

Edge Mobility Architecture — Routeing and Hand-off

This paper presents a network architecture for supporting edge mobility, and goes on to consider IP networks in which the core topology is fixed but where the hosts at the edge of the network may be mobile, as is the case in cellular networks. Within this architecture, mobile enhanced routeing (MER) protocols are used to support the prefix-routed requirements of the fixed Internet, along with the movement of IP addresses allocated to mobile nodes. Specific components for the support of such edge mobility (EMA:MER) are then outlined; these offer fixed/mobile IP network convergence, homogeneous IP handoff across heterogeneous access technologies, and inter-domain roaming across heterogeneous large-scale IP domains.     

一种身份与位置分离环境下基于网络的安全移动性管理协议

针对身份与位置分离(Locator/Identifier Separation Protocol,LISP)环境下的移动性管理问题,提出一种基于网络的安全移动性管理协议—LISP-SMCP(Secure Mobility Control Protocol)。以接入网为移动管理区域,LISP-SMCP有效地支持移动节点在区域内切换和区域间切换,并实现本地认证和双向认证。安全性和性能分析结果表明,LISP-SMCP可以防止中间人、重放和消息篡改等网络攻击,且具有较小的认证时延、切换时延和切换阻塞率。     

Evaluating inter-arrival time in general random waypoint mobility model

In the study of wireless ad hoc networks, the Random Waypoint (RWP) mobility model is extensively used to describe the movement pattern of the hosts. In this paper, we extend our discussion to the general RWP mobility model, where the waypoints may not be uniformly distributed, and hosts may use different distributions to generate their waypoints. In particular, we study a useful property, namely the Inter-Arrival Time (IAT) of hosts to a given area in a network, when the mobility of such hosts is modeled using the random waypoint mobility model. We derive the value of IAT analytically. Three schemes are used to estimate its value. The correctness of our analysis and estimations are verified through simulations. Case studies are also carried out in this paper to show how IAT could be used in the study and applications of mobile wireless networks.     

Traffic load metrics for multihomed mobile IP and global connectivity

Support for host mobility an essential and necessary feature for roaming users who connect to wireless networks via access points. Access points may have different capabilities, be connected to different networks and be installed by different providers. A mobile host will discover multiple access points in this environment. In such an environment, a mobile host should be able to use the best available connection to communicate with a correspondent host and perhaps use multiple connections for different hosts. In areas with wireless local area network access, pockets with limited or no coverage could exist. Such restricted connectivity could be compensated by neighbor hosts who form an ad hoc network and relay packets until they reach an access point. This paper describes and discusses a proposed solution towards enabling and supporting connectivity in wireless networks. In the proposed solution the network layer software will evaluate and decide which wireless network connections to use. A Running Variance Metric (RVM) and a Relative Network Load(RNL) are used to measure the traffic load of access points in wireless access networks. RVM and RNL can be efficiently used for both infrastructure networks and ad hoc networks. Multihomed Mobile IP (M-MIP) is an extension of Mobile IP that enables mobile hosts to use multiple care-of addresses simultaneously. The extension enhances network connectivity by enabling the mobile host, the home agent and correspondent hosts to evaluate and select the best connection. A proposed gateway architecture using M-MIP that integrates wired IP networks with ad hoc networks is described. The M-MIP and gateway architecture using the RVM and RNL metrics have been validated with simulation studies and results are presented.     

A Lease Algorithm to Maintain Strong Mapping Cache Consistency

In the Locator/ID separation protocol (LISP) network, mapping caches are usually used in Ingress tunnel routers to cache recently used identifier-to-locator mappings of remote hosts. When the original mapping in the Egress tunnel router changes, it introduces the problem of cache consistency. In general, the mapping cache supports weak cache consistency by using the time-to-live (TTL) mechanism. However, a stale mapping could lead the packets to a wrong destination. In this paper, we first evaluate the performance of TTL by trace-driven simulation and the results indicate that maintaining strong mapping cache consistency has become an indispensable mechanism in the LISP network. Then we design the lease algorithm to realize the strong consistency and propose analytical models to decide the lease duration based on the state space overhead and the control message overhead, respectively. We present numerical results to estimate the mapping change frequency, to show the impact of different parameters on the lease duration and to explore the relationship between the state space and control message overhead. Finally, we do the trace-driven simulation to compare the lease algorithm to polling-every-time and invalidation in terms of the state space and control messages. The lease algorithm with an appropriate lease duration can balance the state space and the control message overhead while providing strong mapping cache consistency.     

The language of AI and beyond

After Fortran, LISP is the second-oldest high-level programming language in widespread use. Strongly associated with artificial intelligence, its powerful facilities for symbolic processing and incremental development can be of benefit across a wide range of computer applications. The author briefly discusses the use of LISP in AI and then goes on to discuss how LISP works, giving examples of commands used. The structure of programs, environments for LISP, its use, and problems encountered in implementation, are also discussed     

LISP controller: a centralized LISP management system for ISP networks

As the current Internet architecture is suffering from scalability issues, the network research community has proposed alternative designs for the Internet architecture. Among those solutions that adopt the idea of locator/identifier split paradigm, the locator/identifier separation protocol (LISP) has been considered as the most promising solution because of its incrementally deployable feature. Despite various advantages provided by LISP, many ISPs are still conservative to adopt LISP into their production network because the standard LISP does not fully satisfy ISP's requirements on LISP‐enabled services. In this paper, we define ISP's requirements on LISP‐enabled commercial services and describe limitations of the standard LISP from an ISP's perspective. Also, we propose LISP controller, a centralized LISP management system. By using LISP controller, we evaluate three ISP's representative LISP use cases: traffic engineering, virtual machine live migration, and vertical handover. The results show that the proposed LISP controller provides centralized management, controllability, and fast map entry update, without any modifications on the standard LISP. LISP controller allows an ISP to control and manage its LISP‐enabled services while satisfying ISP's requirements. Copyright © 2015 John Wiley & Sons, Ltd.     

Integrated services packet networks with mobile hosts: Architecture and performance

This paper considers the support of real-time services to mobile users in an Integrated Services Packet Network. In the currently existing architectures, the service guarantees provided to the mobile hosts are mobility dependent, i.e., mobile hosts experience wide variation in the quality of service and often service disruption when hosts move from one location to another. The network performance degrades significantly when mobile hosts are provided with mobility independent service guarantees. In this paper we have proposed a service model for mobile hosts that can support adaptive applications which can withstand service degradation and disruption, as well as applications which require mobility independent service guarantees. We describe an admission control scheme for implementing this service model and evaluate its performance by simulation experiments. Simulation results show that, if sufficient degree of multiplexing of the mobility dependent and independent services are allowed, the network does not suffer any significant performance degradation and in particular our admission control scheme achieves high utilization of network resources.     

DHCP及Option82安全机制的原理与实现

动态主机配置协议（DHCP）主要用来动态提供配置参数给因特网上的主机，一方面从DHCP服务器传送主机特定的协议配置参数到主机，同时自动分配网络地址给主机。目前本地局域网大多使用高速公共因特网接入技术和高速调制器，并使用动态主机配置协议分配用户的主机地址。然而，大量的公用主机地址的使用，也会引进安全问题。本文针对目前在局域网普遍使用的DHCP及其为解决安全问题而引进的Option82机制作了简单的描述，并具体阐述其在IPDSLAM的一种具体实现方式。     

Low-Cost Identifiers for Ubiquitous Computing

Any device we want to connect to a global network, e.g. Internet, should have a unique global identifier. However, the size of this identifier can be an unacceptable overhead for devices with limited resources (sensors, toys, disposable devices, micro-robots, etc.), because conventional protocols use full addresses to transmit, process, and store the data required for routing. The usual solution for such devices is to limit the address space to 1 or 2 bytes, but this sacrifices the global unicity of the identifiers. The proposal presented in this article enables devices with limited resources to use reduced addresses that globally identify hosts. We propose the use of abbreviated addresses for routing. We have developed a new protocol named ADSR that takes advantage of these new addresses. This protocol is a modified version of DSR based on the use of abbreviated addresses. The abbreviation procedure can lead to two different nodes having the same address, which we will term collision. ADSR allows rather than avoids collisions. The foundations of this protocol, and some results of an implementation are also presented in this article.     

ID/Locator Split-Based Mobility Scheme for Heterogeneous New Generation Network

The new generation network or the future Internet should treat mobile hosts as first-class objects and allow them to move freely across different networks that use heterogeneous protocols. For this purpose, this paper presents a mobility scheme, designed on the basis of the ID/locator split concept. The scheme provides mobility support from the identity layer, a shim layer inserted between the transport and network layers in the new generation network architecture. Mobility functions are independent of network layer protocols, thus they support mobility across heterogeneous network protocols. These functions are distributed in both end hosts and edge routers so that the scheme provides seamless mobility by reducing handover delay and consequent interruption in communication sessions.     

Novel method for transferring access control list rules to synchronize security protection in a locator/identifier separation protocol environment with cross‐segment host mobility

Extended access control lists (ACLs) are used to filter packets for network security. However, in current network frameworks, ACL rules are not transferred simultaneously with devices that move across network segments. The Internet Engineering Task Force proposed the Locator/Identifier Separation Protocol (LISP), which enables routers (xTRs) to configure ACL rules for blocking immobile endpoint identifiers (EIDs). However, when an EID moves from the original xTR to a new xTR, the ACL rules at the original xTR cannot be transferred with the EID. Thus, the new xTR lacks the corresponding ACL rules to effectively block the EID, resulting in security risks. The highlights of this study are as follows. First, a method is proposed for dynamically transferring ACL rules in LISP environments and frameworks. Second, the map‐register and map‐notify protocols were combined to encapsulate and transfer the ACL rules and thus obviate an additional process required to transfer these rules. Third, the experimental results verified that the proposed method can be used to achieve synchronized security protection in an LISP environment involving cross‐segment EID movements.     

一种基于位置和标识分离的移动性管理解决方案

基于位置和标识分离的解决方案不能很好地同时解决移动性支持和可扩展性差的问题,并且难于部署。文章提出一种新的基于位置和标识分离的网络架构,并给出与该架构相适应的移动性管理解决方案。该方案不仅能很好地解决网络的可扩展性问题,在移动性支持方面还具有如下的特点:不需要修改终端协议栈,易于部署;标识符含有一定的路由信息,能提供较好的与传统终端互通的能力;将映射系统分布于边缘网络内,增强了系统的鲁棒性并降低了切换时延。     

MRSVP: A Resource Reservation Protocol for an Integrated Services Network with Mobile Hosts

This paper describes a reservation protocol to provide real-time services to mobile users in an Integrated Services Packet Network. Mobility of hosts has significant impact on the quality of service provided to a real-time application. The currently proposed network system architecture and mechanisms to provide real-time services to fixed hosts are inadequate to accommodate the mobile hosts which can frequently change their point of attachments to the fixed network. Mobile hosts may experience wide variations of quality of service due to mobility. To reduce the impacts of mobility on QoS guarantees, a mobile host needs to make advance resource reservations at multiple locations it may possibly visit during the lifetime of the connection. The currently proposed reservation protocol in the Internet, RSVP, is not adequate to make such reservations for mobile hosts. In this paper, we describe a new reservation protocol, MRSVP, for supporting integrated services in a network with mobile hosts.     

Secure hosts auto-configuration in mobile ad hoc networks

All existing routing protocols of Mobile Ad Hoc networks (MANET) assume that IP addresses of hosts are already configured before they join the network. In traditional schemes, this task is delegated to the dynamic host configuration protocol (DHCP [R. Droms, Dynamic host configuration protocol, RFC 2131, March 1997]), which allots an IP address to each requesting node. However, this process can not be applied in the context of MANET because of the lack of infrastructure and the great mobility that characterize them. A manual management of the addresses can be considered as long as the number of nodes remains reasonable. On the other hand, it is not possible any more since the network reaches a certain size. Some works proposed solutions to allow an automatic configuration of the nodes, i.e. without human intervention. Unfortunately these processes, often inspired of the traditional wired networks, are not always well adapted to MANET and appear relatively greedy concerning for example the delay, the address space or the bandwidth. Moreover, they apply only to ideal networks in which all nodes can trust each other. In this manner, they do absolutely not consider the security aspects and are thus not adapted to a real use in potentially hostile environment. In this paper, we propose a node auto-configuration scheme which uses the buddy system technique to allocate the addresses, as well as an algorithm allowing to authenticate the participants inside the network.     

Dynamic hierarchical mobility management strategy for mobile IP networks

One of the major challenges for the wireless network design is the efficient mobility management, which can be addressed globally (macromobility) and locally (micromobility). Mobile Internet protocol (IP) is a commonly accepted standard to address global mobility of mobile hosts (MHs). It requires the MHs to register with the home agents (HAs) whenever their care-of addresses change. However, such registrations may cause excessive signaling traffic and long service delay. To solve this problem, the hierarchical mobile IP (HMIP) protocol was proposed to employ the hierarchy of foreign agents (FAs) and the gateway FAs (GFAs) to localize registration operations. However, the system performance is critically affected by the selection of GFAs and their reliability. In this paper, we introduce a novel dynamic hierarchical mobility management strategy for mobile IP networks, in which different hierarchies are dynamically set up for different users and the signaling burden is evenly distributed among the network. To justify the effectiveness of our proposed scheme, we develop an analytical model to evaluate the signaling cost. Our performance analysis shows that the proposed dynamic hierarchical mobility management strategy can significantly reduce the system signaling cost under various scenarios and the system robustness is greatly enhanced. Our analysis also shows that the new scheme can outperform the Internet Engineering Task Force mobile IP hierarchical registration scheme in terms of the overall signaling cost. The more important contribution is the novel analytical approach in evaluating the performance of mobile IP networks.     

间接接入—— 一种新的移动客户机的接入模型

为了使移动客户机能高效地接入互联网络，对含有移动主机的网络提出了一种辐射式、间接接入的新方法。根据这种新方法，需对ＯＳＩ模型的每一层，甚至包括应用层的协议作较大的修正。同时根据移动通信的特点，还提出了在移动客户端及其接入点进行分离处理的建议，以使其区别于网络的其它部分。