共查询到20条相似文献,搜索用时 15 毫秒
1.
A new ATM adaptation layer for TCP/IP over wireless ATM networks 总被引:3,自引:0,他引:3
This paper describes the design and performance of a new ATM adaptation layer protocol (AAL‐T) for improving TCP performance
over wireless ATM networks. The wireless links are characterized by higher error rates and burstier error patterns in comparison
with the fiber links for which ATM was introduced in the beginning. Since the low performance of TCP over wireless ATM networks
is mainly due to the fact that TCP always responds to all packet losses by congestion control, the key idea in the design
is to push the error control portion of TCP to the AAL layer so that TCP is only responsible for congestion control. The AAL‐T
is based on a novel and reliable ARQ mechanism to support quality‐critical TCP traffic over wireless ATM networks. The proposed
AAL protocol has been validated using the OPNET tool with the simulated wireless ATM network. The simulation results show
that the AAL‐T provides higher throughput for TCP over wireless ATM networks compared to the existing approach of TCP with
AAL 5.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Cheng M. Rajagopalan S. Li Fung Chang Pollini G.P. Barton M. 《Communications Magazine, IEEE》1997,35(11):82-92
As broadband multimedia services and wireless services become popular, there is growing interest in the industry to support ATM over a wireless link, and wireless access to fixed ATM networks. We focus on the internetworking of PCS and ATM networks, in which the air interface remains one of the PCS standards and the backbone is an ATM network with mobility support. It is desirable to minimize the impact of the internetworking and mobility support on the existing/emerging PCS and ATM specifications. A network architecture, a protocol reference model, and signaling protocols for PCS mobility support over fixed ATM networks are described. They are compared against other implementation alternatives and the trade-offs are discussed. Some performance results of the proposed architecture are also presented 相似文献
3.
Lee Heesang Song Hae‐Goo Chung Ji‐Bok Chung Sung‐Jin 《Telecommunication Systems》2000,14(1-4):243-267
The survivability for ATM based B‐ISDN has become an important challenge for telecommunication network planners and engineers.
In this paper, we consider multiple grades of reliability concept and a multilayer survivable network architecture for survivable
ATM networks. We address two complementary ATM VP restoration schemes in this paper. First, we propose preplanned rerouting
models and algorithms based on combinatorial optimization to prepare efficient backup VP configuration. We test two formulations
and algorithms for this problem. Efficient column generation technique to solve linear programming relaxation and strong valid
inequalities incorporating the branch‐and‐bound scheme are suitable to solve the problem to optimality within small time limits.
Second, we propose a new dynamic VP path restoration scheme to restore nonprotected VPs by the preplanned rerouting. Our protocol
has shown the advantage in restoration effectiveness comparing a well‐known protocol in computational simulation. We, finally,
address the relationships between the suggested models of this paper and the expected results of our ongoing project.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
A novel network architecture based on the IEEE 802.6 metropolitan area networks (MAN) is proposed to integrate the wireless
and wired segments of a regional enterprise network (REN) within a city. This architecture functions like a distributed switch
for all types of services, reducing traffic congestion by sharing the high capacity link dynamically and facilitating signaling,
mobility management, call processing and network management through its distributed functions, transport facilities and broadcasting
capability. It also serves as a peripheral gathering network of REN traffic for transport over a wide area ATM/BISDN, enabling
integration of an enterprise's regional networks into a global EN. Two major wireless applications, i.e., wireless PABX (WPABX)
and wireless LAN (WLAN) are discussed to illustrate the advantages of this MAN‐based architecture. Although a REN is likely
to support a wide range of different services, voice and data will continue to be the predominant traffic generated by WPABXs
and WLANs, respectively, and are also representative of isochronous and asynchronous multimedia traffic carried by future
wireless networks. We compare the traffic capacity of several voice transport alternatives under integrated (voice/data) network
traffic with various data traffic loads, and study voice and data integration under three different integration schemes by
simulations. Results indicate that the MAN‐based architecture is most effective employing queue arbitrated (QA) access for
asynchronous traffic, pre‐arbitrated access for constant bit‐rate isochronous traffic, and the new reservation arbitrated
(RA) access for variable bit‐rate isochronous traffic, under a scheme that permits full sharing between QA and RA traffic.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Lee Soon Seok Lee Jeong Gyu Oh Chang Hwan Kim Young Boo Kim Young Sun 《Telecommunication Systems》2000,14(1-4):269-290
In this paper, we present the basic idea and some concepts for the architecture of the ATM switching system being developed
in ETRI of KOREA, and also describe its performance. RSE (Reference Service Entity) concept is introduced to define the characteristics
of user’s traffic. This concept is useful to represent the demand of CPE (Customer Premise Equipment) user sets and one of
point‐to‐multipoint connections. We also propose RUCA (Reference Units for Connection Attempts) concept with which we can
illustrate the call/connection level performance of the ATM switching system. This concept can be applied for measuring the
call processing capability in both point‐to‐multipoint connections and multipoint‐to‐multipoint connections when call set‐up
between users is performed by a sequence of point‐to‐point connections basis. From the basic concepts and the recommendations
of ITU‐T, the design objective of the system performance is specified. We represent the methodologies for dimensioning the
system to achieve the design objectives, and estimate the system performances. Then we show that our developing system has
suitable performance to accommodate the future B‐ISDN.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
Sivalingam Krishna M. Chen Jyh‐Cheng Agrawal Prathima Srivastava Mani B. 《Wireless Networks》2000,6(1):73-87
This paper describes the design and analysis of a low‐power medium access control (MAC) protocol for wireless/mobile ATM networks.
The protocol – denoted EC‐MAC (energy conserving medium access control) – is designed to support different traffic types with
quality‐of‐service (QoS) provisions. The network is based on the infrastructure model where a base station (BS) serves all
the mobiles currently in its cell. A reservation‐based approach is proposed, with appropriate scheduling of the requests from
the mobiles. This strategy is utilized to accomplish the dual goals of reduced energy consumption and quality of service provision
over wireless links. A priority round robin with dynamic reservation update and error compensation scheduling algorithm is
used to schedule the transmission requests of the mobiles. Discrete‐event simulation has been used to study the performance
of the protocol. A comparison of energy consumption of the EC‐MAC to a number of other protocols is provided. This comparison
indicates the EC‐MAC has, in general, better energy consumption characteristics. Performance analysis of the proposed protocol
with respect to different quality‐of‐service parameters using video, audio and data traffic models is provided.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
As infrared wireless LANs for in-building applications become more popular because of their many advantages, it is of interest to design such LANs to support the ATM protocol and therefore provide wireless access to fixed ATM networks. The architecture of such a LAN is presented in this article. Emphasis is placed on the protocol stacks of the model to provide seamless operation with the wired network, on the cellular topology, and on the MAC protocol. Under the proposed topology the system performance is revealed in terms of packet dropping probability, average access delay, channel throughput, and statistical multiplexing gain for a range of system parameters 相似文献
8.
9.
The flexibility offered by the ATM transport mechanism and its potential capabilities, together with its compatibility with
the B‐ISDN, makes ATM the prime candidate for the support of multimedia services over the wireless medium. However, technical
issues remain to be resolved in relation to the feasibility of ATM for the support of mobility over the radio interface. This
paper examines network issues in supporting handover in a wireless ATM network. In particular, analysis has been performed
for a virtual tree-based network architecture. Results have shown that by using multicast transmission and by using a distributed
numbering algorithm, the potential problems of cell-loss and cell-duplication have been eliminated.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
LMDS/LMCS is a broadband wireless local loop, millimeter‐wave alternative to emerging integrated multiservice access networks.
Significantly large amounts of bandwidth – in the order of one GHz of spectrum – are made available to residential subscribers
or supported business users respectively that employ highly directional antennas and signal polarization to establish communication
with a central hub. Besides the requirement for dynamic bandwidth allocation capabilities, these networks should be able to
guarantee negotiated quality of service (QoS) levels to a number of constant‐length (ATM) – and possibly variable length (TCP/IP)
– packet streams. In this context, we analyze the performance of contention, polling/probing and piggybacking mechanisms that
will be used by the LMDS MAC protocol for the dynamic support of both real‐time and non‐real‐time traffic streams. More specifically,
we focus on the end‐to‐end performance of a real‐time variable bit rate connection for which the LMDS link is only the access
component of a multi‐link path through an ATM network. Results are presented on maximum end‐to‐end cell delays under a Weighted
Round Robin service discipline and buffer requirements are calculated for no‐loss conditions. In parallel, we also consider
the case in which variable length IP packet traffic is supported as such by the same wireless access network. Backbone interconnection
alternatives of LMDS hubs, multiple access proposals and scheduling algorithms are addressed in this framework.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
Heo Jeong Won Byun Sung Hyuk Lee Ju Yong Sung Dan Keun Lee Soo Jong 《Telecommunication Systems》2000,14(1-4):291-309
A B‐ISDN national project in Korea has been carried out to develop a National Information Superhighway since 1992. An ATM
switching system has been developed as one of the most important parts in the project, and has been tested in the National
Information Superhighway testbed. In this paper, we develop a cell‐level/call‐level ATM switch simulator using cell‐level
and call‐level input traffic models for evaluating the ATM switching system. The cell‐level simulator models various cell‐level
switching functions such as priority control and multicast, and evaluates the cell‐level performance indices of the ATM switch
in terms of cell delay, throughput, and cell loss probability. On the other hand, the call‐level simulator uses call‐level
traffic models and evaluates the call blocking rate as a call‐level quality of service (QoS).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
Kim Duk Kyung Lee Seung Joon Choi Dae Woo Sung Dan Keun 《Telecommunication Systems》2000,14(1-4):75-93
In this paper, we propose an ATM‐based Personal Communication Service (PCS) network architecture with ring‐based access networks.
We also propose a simple ring management scheme using ATM Add‐Drop‐Multiplexers (ADM). The ring has a Virtual Star topology,
and we manage its bandwidth at two levels: Virtual Path (VP) level and Virtual Channel (VC) level. We consider four different
types of configurations according to the locations of visitor location register (VLR) and mobile switching center (MSC) functions,
and obtain signaling load and processing load. A 150 Mb/s‐dual ring can support about 5,500 homogeneous ON–OFF voice sources.
This ring capacity corresponds to covering approximately 180 cells in the case of 30 connections per cell. Even though we
are here concerned with evaluating the proposed network for voice traffic, we can extend this study to the analysis of the
proposed ATM‐based PCS network accommodating various types of multimedia traffic as a further study.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
13.
This paper presents an ATM-based transport architecture for next-generation multiservices personal communication networks (PCN). Such “multimedia capable” integrated services wireless networks are motivated by an anticipated demand for wireless extensions to future broadband networks. An ATM compatible wireless network concept capable of supporting a mix of broadband ISDN services including constant bit-rate (CBR), variable bit-rate (VBR), and packet data transport is explored from an architectural viewpoint. The proposed system uses a hierarchical ATM switching network for interconnection of PCN microcells, each of which is serviced by high-speed, shared-access radio links based on ATM-compatible cell, relay principles. Design issues related to the physical (modulation), media access control (MAC), and data-link layers of the ATM-based radio link are discussed, and preliminary technical approaches are identified in each case. An example multiservice dynamic reservation (MDR) TDMA media access protocol is then considered in further detail, and simulation results are presented for an example voice/data scenario with a proportion of time-critical (i.e., multimedia) packet data. Time-of-expiry (TOE) based queue service disciplines are also investigated as a mechanism for improving the quality-of-service (QoS) in this scenario 相似文献
14.
The concept of wireless ATM is now being actively considered as a potential framework for next-generation wireless communication networks capable of supporting integrated multimedia services with different QoS requirements. Several key subsystem design issues for wired ATM and wireless networks need to be readdressed in the scope of the wireless ATM. One of the main key subsystem issues is the development of the appropriate medium access control (MAC) protocol, which has the capability to extend the statistical multiplexing of the wired ATM network into the wireless medium. In this article the authors address the problem of a suitable MAC protocol for the specification of a wireless ATM network and outline the design objectives. In addition, the authors address some other challenging key issues that the wireless medium and wireless network architecture impose on the ATM stack protocol 相似文献
15.
One of the major design issues in wireless ATM is the support of inter‐switch handoff. An inter‐switch handoff occurs when
a mobile terminal moves to a new base station connecting to a different switch. Recently, a two‐phase handoff protocol has
been proposed to support inter‐switch handoff in wireless ATM networks. With the aim of shortening handoff delay while using
the network resources efficiently, the two‐phase handoff protocol employs path extension for each inter‐switch handoff, followed
by path optimization if necessary. To implement the two‐phase handoff protocol efficiently, we need to determine when to trigger
path optimization. In this paper, we propose and analyze three path optimization schemes, namely: periodic, exponential, and
Bernoulli, for the two‐phase handoff protocol. The design objective is to determine the time to invoke path optimization such
that the average cost per connection is minimized. We develop a discrete time analytical model and a discrete‐event simulation
model for comparing the performance of the three path optimization schemes. Results indicate that the Bernoulli path optimization
scheme outperforms the other two schemes by providing a lower average cost per connection. The proposed models can also be
adapted to analyze other path optimization schemes in general.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
Marsan M. Ajmone Chiasserini C.F. Fumagalli A. Lo Cigno R. Munafò M. 《Wireless Networks》2001,7(4):425-436
This paper presents a handover protocol for wireless ATM networks, which makes use of in-band signaling, i.e., of ATM resource management cells, to process network handovers and guarantee the in-sequence and loss-free delivery of the ATM cells containing user data. The goal of the proposed approach is to minimize the modifications of the ATM signaling standard required to overlay user mobility onto the fixed network infrastructure, and provide for a gradual upgrade of the fixed network to handle mobility. The proposed protocol handles both local handovers, in which the connection access point needs not migrate to a new ATM local exchange, and global handovers, in which the connection access point must migrate to a new local exchange. The handover scheme is devised so as to grant in-sequence delivery of cells. The performance of the network during handover is analyzed in case of connections requiring loss-free operation. The considered performance figures are the cell transmission delay introduced by the handover and the cell buffering requirements posed to the network. The behavior of the proposed protocol in presence of multiple handovers is studied via simulation, while a simple analytical method is derived for the performance evaluation of a single handover in isolation. 相似文献
17.
Wireless ATM networks: technology status and future directions 总被引:3,自引:0,他引:3
Raychaudhuri D. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1999,87(10):1790-1806
The concept of “wireless ATM” (WATM), first proposed in 1992, is now being actively considered as a potential framework for new-generation wireless communication networks capable of supporting integrated, quality-of service (QoS) based multimedia services. In this review paper, we outline the technological rationale for wireless ATM, present a system-level architecture, and discuss key design issues for both mobile ATM switching infrastructure and radio access subsystems. The WATM radio access layer issues covered in this paper include: spectrum allocation; spectrum etiquette; modem technology; and medium access/data link control (MAC/DLC) protocols. Mobile ATM aspects such as ATM signaling extensions for handoff control, location management, and mobile QoS control are discussed. A summary of current wireless/mobile ATM technology development and standardization status is given, including an outline of our WATMnet prototype. The paper concludes with a discussion of future directions for wireless ATM technology such as Internet protocol (IP) integration and mobile multimedia terminals/applications 相似文献
18.
Multicasting is a desired function in both wired and wireless networks. Currently, multicasting‐based applications have pervasive
presence and influence in our Internet. Wireless ATM aims to support different traffic types over a high speed wireless network.
In particular, traditional approaches towards multicasting in wired networks cannot be directly applied to mobile ATM networks.
This includes the mechanism proposed to handle mobility in wired networks. In this paper, we address the issues behind multicasting
in wireless ATM networks and the underlying mechanisms to support handoffs of both unicast and multicast connections. Through
simulation, we evaluated the performance of optimal core‐based tree (CBT), late‐joined CBT, optimal source‐based tree (SBT),
and late‐joined SBT during changing multicast host membership conditions. In addition, we evaluated the impact of multicast
receivers' migration on the total link cost of the resultant multicast tree. Simulation results revealed that source‐based
trees incur more total link costs under both dynamic host membership and receivers' migration scenarios. However, it generates
less control messages than the distributed CBT and SBT approaches.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
19.
Wireless ATM LAN with and without infrastructure 总被引:1,自引:0,他引:1
Yonggang Du Herrmann C. May K.P. Hulyalkar S.N. Evans D. 《Communications Magazine, IEEE》1998,36(4):90-95
We consider wireless ATM concepts for small LANs, especially for SOHO and future consumer applications. We describe a wireless ATM LAN framework architecture that supports wireless ATM communications in environments with and without fixed ATM infrastructure. For the configuration with an ATM infrastructure, a distributed ATM switched backbone is proposed, which enables a smart ATM switching element to be embedded in every wireless and fixed access point. For bandwidth efficiency and ease of operation (place-and-play), we also propose an ad hoc wireless ATM LAN concept based on the same 5 GHz wireless ATM air interface as is currently under standardization in the ETSI/BRAN and ATM Forum. Unlike CSMA-based ad hoc systems such as HIPERLAN and IEEE802.11, our ad hoc wireless ATM system makes QoS management feasible in an infrastructureless environment by using resource reservation and scheduled medium access protocol. Since cost scalability is essential throughout our system design, we consider forwarding between ad hoc subnets and interworking with the fixed network as important but optional features 相似文献
20.
Architecture and experimental results for quality of service in mobile networks using RSVP and CBQ 总被引:3,自引:0,他引:3
Efforts are underway to enhance the Internet with Quality of Service (QoS) capabilities for transporting real‐time data. The
issue of wireless networks and mobile hosts being able to support applications that require QoS has become very significant.
The ReSerVation Protocol (RSVP) provides a signaling mechanism for end‐to‐end QoS negotiation. RSVP has been designed to work
with wired networks. To make RSVP suitable for wireless networks, changes need to be made by: (i) changing the way control
messages are sent, and (ii) introducing wireless/mobile specific QoS parameters that take into account the major features
of wireless networks, namely, high losses, low bandwidth, power constraints and mobility. In this paper, an architecture with
a modified RSVP protocol that helps to provide QoS support for mobile hosts is presented. The modified RSVP protocol has been
implemented in an experimental wireless and mobile testbed to study the feasibility and performance of our approach. Class
Based Queueing (CBQ) which is used as the underlying bandwidth enforcing mechanism is also modified to fit our approach. The
experimental results show that the modified RSVP and CBQ help in satisfying resource requests for mobile hosts, after handoff
occurs. The experiments also show how different power and loss profile mechanisms can be used with our framework. The system
performance using the modified RSVP control mechanism is also studied.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献