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1.
孙长永  余敬东 《通信技术》2010,43(5):138-139,142
流传输控制协议(SCTP协议)是一种新的Internet传输层协议,Internet工作组设计SCTP的最初目的是在IP网络上传输PSTN信令消息,而且还能够充当通用传输协议。与传统的传输协议相比,SCTP协议允许在一个单一的连接中传输多个数据子流,这种功能可以大大改善高损耗的环境中多媒体流延迟问题,同时SCTP协议支持多宿功能,能够为网络提供冗余备份功能。对SCTP故障恢复机制进行了改进,充分利用SCTP多宿特性为移动Ad hoc网络提供可靠性保障,使其能够适应移动Ad hoc网络的特点,仿真结果表明:该功能极大地减少了故障恢复时间,提高了其在移动Ad hoc网络中的性能。  相似文献   

2.
Wireless Personal Communications - TCP (Transmission Control Protocol) is a protocol of layer four (Transport Layer), and IP (Internet Protocol) is in the Network Layer (Layer 3) of the OSI Model....  相似文献   

3.
Internet firewalls are typically configured to allow web friendly traffic transported by means of the Transmission Control Protocol (TCP) and, simultaneously as security measure, reject any other type of transport. This is a problem for real time communications that heavily rely on transport types like User Datagram Protocol or those associated to the Internet Security Protocol. A mechanism to overcome this limitation is through stream tunneling where media frames that would be typically rejected by firewalls are encapsulated on top of TCP transport. In this paper, a novel mathematical model that links application layer packet loss to bursty network packet loss in the context of fading channels characteristic of wireless communications is presented for both, datagram and stream encapsulation. This model is compared with experimental scenarios of tunneling applied to state of the art speech codecs such that quality scores are obtained and correlated against theoretical results.  相似文献   

4.
流控制传输协议研究   总被引:3,自引:0,他引:3  
文章介绍了流控制传输协议(SCTP)的主要特点:支持多穴主机,支持消息的无序递交,提供端到端的可靠性,提供面向消息的传输,提供相对TCP增强的流量控制和拥塞控制,提供更好的安全性和可扩展性;分析了SCTP的主要应用,强调作为一种通用的传输层协议SCTP是今后发展的方向;综合考察了当前SCTP的研究进展,并给出了相关结论,认为SCTP是一种功能强大的传输层协议.  相似文献   

5.
Wireless Personal Communications - Transmission Control Protocol (TCP) provides connection oriented and reliable transport layer services. Mobile Adhoc Networks (MANETs) are autonomous and...  相似文献   

6.
Katz  D. Ford  P.S. 《IEEE network》1993,7(3):38-47
The Connectionless Network Protocol (CLNP), which is supported by the associated OSI routing protocols, is proposed as a replacement for the Internet Protocol (IP). The basis of the proposal is to run the Internet transport protocols, the Transmission Control Protocol (TCP), and the User Datagram Protocol (UDP) on top of CLNP in an approach known as TCP and UDP with bigger addresses (TUBA). The fundamentals of CLNP and the OSI connectionless routing architecture, the operation of the IP suite with CLNP replacing IP, the support of Internet applications operating on top of TUBA, and a transition plan to a TUBA Internet are discussed  相似文献   

7.
Mobile telecommunication new services are based on data networks specially Internet. These services include http, telnet, ftp, Simple Mail Transfer Protocol, etc. Besides, we recognize a mobile network as a multiuser network. Transmission Control Protocol (TCP)/Internet Protocol which is sensitive to link congestion in wireline data links is also used in wireless networks. In order to improve the system performance, the TCP layer uses flow control and congestion control. Besides, radio link control (RLC) and medium access control sublayers have been introduced to compensate the deficiency of TCP layer in wireless environment. RLC has an important role in quality of service enhancement of the Universal Mobile Telecommunications System (UMTS). In this paper, we review the protocol stack of UMTS Terrestrial Radio Access Network which is based on Third-Generation Partnership Project. Then, we evaluate its layer 2 error control mechanisms and verify TCP over automatic repeat request error control mechanism and finally quality of service improvement results from it in fading channels.  相似文献   

8.
A solution to the lack of interoperability between the U.S. Department of Defense (DoD) data communications standards and the NATO standards based on the International Organization for Standardization concept for open systems interconnection is presented. The solution is based on conversion between a common subset of the US DoD Transmission Control Protocol and the ISO Class 4 Transport Protocol at the Transport layer, which is the first layer offering any end-to-end service.  相似文献   

9.
mSCTP for soft handover in transport layer   总被引:1,自引:0,他引:1  
In this letter, we discuss mobile Stream Control Transmission Protocol (SCTP) for soft handover in the transport layer. From the experimentations on triggering rules for Add-IP and Primary-Change during the handover, it is shown that the aggressive Add-IP and conservative Primary-Change rules provide better throughput.  相似文献   

10.
This article reviews the steps necessary to configure and implement a complex router internetwork. This article will specifically concentrate on Cisco routers, and since they support Transmission Control Protocol/Internet Protocol (TCP/IP) natively, it will concentrate on a backbone network employing that protocol.  相似文献   

11.
An analysis of TCP processing overhead   总被引:12,自引:0,他引:12  
The transport layer of the protocol suite, especially in connectionless protocols, has considerable functionality and is typically executed in software by the host processor at the end points of the network. It is thus considered a likely source of processing overhead. However, a preliminary examination has suggested to the authors that other aspects of networking may be a more serious source of overhead. To test this proposition, a detailed study was made of the Transmission Control Protocol (TCP), the transport protocol from the Internet protocol suite. In this set of protocols, the functions of detecting and recovering lost or corrupted packets, flow control, and multiplexing are performed at the transport level. The results of that study are presented. It is concluded that TCP is in fact not the source of the overhead often observed in packet processing, and that it could support very high speeds if properly implemented  相似文献   

12.
详细描述了流控制传输协议SCTP。SCTP设计用于在IP网络上传输PSTN信令,但它可以有更广阔的用途。  相似文献   

13.
The IEEE 802.21 Media Independent Handover (MIH) working group is developing a set of mechanisms to facilitate migration of mobile users between access networks that use different link-layer technologies. Among these are mobility managers that create and process signaling messages to facilitate handovers. The MIH signaling architecture being developed in the Internet Engineering Task Force (IETF) allows any transport layer protocol to carry MIH messages. The IETF has considered using the unreliable but lightweight transport available with the User Datagram Protocol (UDP) as well as the reliable stream-oriented transport with congestion control offered by the Transmission Control Protocol (TCP). In this paper we develop mathematical models that result in expressions for the characteristic function of the time required to complete exchanges of an arbitrary number of MIH signaling messages between a mobile node (MN) and a remote mobility manager (MM). Our models also provide expressions for the average amount of overhead associated with MIH message exchanges due to retransmissions either by the MIH signaling entities or by the transport-layer protocol. In addition, we provide simulation results that confirm the results from the mathematical model and illustrate the effect of varying transport parameters such as the TCP maximum retransmission timeout.  相似文献   

14.
ABR和UBR业务模型的TCP接入分析   总被引:1,自引:0,他引:1  
ABR和UBR业务是ATM中新定义的业务类型,主要面向数据传输服务。TCP是目前最为流行的数据输协议,采用基于窗口的拥塞控制机制。本文主要讨论了TCP接入ABR和UBR业务时所呈观的一些特点及ATM交换机缓存的大小对TCP性能的影响。  相似文献   

15.
针对无线上行链路的TCP跨层改进机制   总被引:1,自引:0,他引:1  
在下一代蜂窝通信系统(例如,4G)里,传输控制协议(TCP)做为主要的端到端传输协议将随着互联网业务的开展而得到相当广泛的应用。本文根据上行无线链路对TCP的影响,提出了一种针对上行链路的TCP改进机制。该机制利用无线链路控制层(RLC)的反馈信息,实现了对TCP层定时器的自适应控制,从而大大降低了上行无线链路对TCP性能的影响。仿真结果表明,同传统的TCP机制相比,本文提出的TCP改进机制能够使得TCP在可靠性低,突发错误时间长以及切换时延高的无线移动环境更为有效地工作。  相似文献   

16.
A comprehensive context management approach is necessary in the era of ubiquitous technologies, and efficient context data collection is one of the most fundamental and important processes for realizing comprehensive context management. Traditional context data collection approaches are based on Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) over Internet Protocol (IP), which has several disadvantages, such as lack of efficient mobility support, security and data transfer efficiency. Content‐Centric Networking (CCN), on the other hand, provides advantages in terms of mobility, security and bandwidth efficiency in comparison with IP. In this paper, we introduce our user‐centric comprehensive context management framework, and propose a secure and efficient context data collection and provision approach based on the framework using CCN as a network and transport layer. This context collection approach provides a flexible security mechanism by introducing three levels of security type. It also provides bandwidth efficiency by taking advantage of CCN's content caching; performance evaluation results show that our approach can reduce bandwidth consumption up to 99% for pull and up to 46% for push in comparison to a UDP/IP‐based system. Our approach also provides advantages in supporting mobility and leveraging multiple interfaces. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

17.
In high bandwidth, low latency data center networks, when multiple data senders simultaneously communicate with a single receiver, namely in many‐to‐one communication pattern, the burst data overload the receiver's switch buffers, which leads to Transmission Control Protocol (TCP) throughput collapse. This is the so‐called TCP Incast problem. It has become a new hot research topic in recent years. Also, many proposals have been put forward from the aspects of multiple layers including link layer, transport layer, and application layer, etc., to mitigate TCP Incast. In this paper, an in‐depth survey on these proposals is given, and the principles, merits, and drawbacks of the main proposals for solving the TCP Incast issue are analyzed and summarized. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

18.
SCTP (Stream Control Transmission Protocol) is a protocol of the TCP/IP stack, initially conceived for transport of telephony signaling messages. This article shows a series of performance tests executed on the Linux Kernel SCTP implementation (LK-SCTP).  相似文献   

19.
This article outlines some basic performance characteristics of the Transmission Control Protocol/Internet Protocol (TCP/IP) over Frame Relay/Asynchronous Transfer Mode (FR/ATM) Service Interworking. The conclusions are based on empirical TCP/IP performance test results collected on a FR/ATM Service Interworking testbed, architected with commercially available IP, FR, and ATM equipment. © 1998 John Wiley & Sons, Ltd.  相似文献   

20.
《Spectrum, IEEE》1990,27(1):35-37
The growing use of local area networks during 1989 is examined. The fiber distributed data interface (FDDI), a 100 Mb/s dual-ring, optical fiber LAN that is nearing approval by the American National Standards Institute, is discussed. Other developments reviewed are the increasing support for the Internet Transmission Control Protocol/Internet Protocol, setbacks in promoting the OSI (open systems interconnection) approach due mainly to the scarcity of products and weak sales, work on ways to bridge the two sets of protocols, and the emergence of high-speed networking as a viable technology  相似文献   

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