毕业论文(设计)基于NGN 远程监控系统的指令设计.doc
基于NGN远程监控系统的指令设计孟治国(1. 广东轻工职业技术学院电子通信系, 广东广州 510300)【摘要】基于下一代网络的远程多级监控系统迎合了网络融合的趋势,文章基于SIP等协议、视频网关编解码技术,为各种SIP路由器及用户代理端产品设计了指令系统,实现了流媒体传输、视频采集和指令下发等操作,系统在进行数据传输及控制时建立了双向双通道,保证了不同资源的分流,更有效地利用了设备服务和网络通信。【关键词】下一代网络NGN;远程监控;指令设计; 0 引言一直以来,视频监控在许多场合承担着重要的安防任务,随着数字化、网络化和智能化技术的发展,多级监控系统逐渐受到用户的关注。远程多级监控结合了计算机控制、声视频技术、流媒体传输、地理定位、自动识别等技术,通过公共通讯网络实现了对下一级或远端监控点控制,扩展了图像上传、下发信息、监控云台、双向对讲等功能。随着数据量传输的增加,网络存储向后迁移和后台信息提供更多新功能,造成服务器负担过重,如何利用接口系统和路由设备,优化指令来分流数据,保证任务更合理分派值得探索。1 主要技术基于下一代网络(NGN)的远程多级监控方案迎合了网络融合的趋势,由统一的网管系统控制多路的数字前端监控设备,为NGN提供具有实时性要求的业务呼叫控制和连接控制功能。软交换技术可谓是NGN的核心技术之一,它直接决定了下一代网络功能的强弱,软交换使用的呼叫、会话控制协议主要有实时传输协议(RTP)、实时控制协议(RTCP)、H323协议族、SlPSOP协议和BICC协议等几种。会话初始化协议(Session Initiation Protocol,SIP)在软交换技术中占有重要地位,由IETF的MMUSIC(Multi- party Multimedia Session Control)工作组提出,SIP是一个应用层控制协议,它能建立、修改和终止多媒体会话,具有采用文本编码、使用请求/响应模式、建立会话和描述会话分离、采用端到端的协议、互操作性好等特点1,SIP将成为NGN中的核心控制协议,对NGN的大规模商用具有十分重要的意义。下一代网络的SIP(NGN SIP)还在不断发展中,NGN SIP对IETF SIP加以了限定和扩充,其协议体系在很大程度上引用IETF的标准或草案作为基础,而后加以整合,根据NGN的特点和要求,NGN SIP的标准化还有很多方面的工作。本设计基于SIP、RTPRTCP协议、网络摄像机、视频网关的编解码技术,形成了SIP路由器及各种UA(用户代理端)产品,应用于远程多级监控资源通信平台,实现了即时传输程序的单元集成2。协议互通测试采用符合国际技术标准的X-Lite 网络视频软电话、sip通信器、Wireshark等开源标准工具,目的是逐渐替代复杂的H.323音视频会话控制协议,从远程监控数据领域,扩展到了多个通信应用领域。基于Oracle的数据及通信服务器架构技术,开发SIP服务器、SIP路由器,开发语言用JAVA,开发工具用太阳微系统公司的NetBean 6.8。采用开源PJSIP(http:/www.pjsip.org)及JRTP(http:/www.jrtp.org)技术,开发带SDP媒体特性的SIP User Agent (简称UA),其开发语言用C+,开发工具用Microsoft.Net Studio 2005。2系统架构远程多级监控系统主要由各级监控中心和终端组成树状结构,各级监控中心是服务器指令中心、资源交互平台和下一级的路由中继,终端是系统末级单元,充任拾取数据和管理用户设备作用,多级结构依靠传输网络组成有机的监控系统。监控系统架构如图1所示,服务端设备包括视频交换网关、SIP路由器、系统管理服务器、视频矩阵、WEB服务器、网络存储服务器、数据库服务器、显示设备等。服务端接口硬件出于兼容、扩展和指令程序的要求,设计出UA通信接口、SIP通信接口、控制接口等各类接口,将来有新设备或下级系统接入,只需要添加必要的接口和指令,很容易融合到大系统。在服务器系统和系统接口之间,按照安全、分工和指令分类,抽象出事务实现层、业务逻辑层、SIP Servlet等,其中SIP Servlet是本系统设计的特点,在树状结构中起统筹作用。独立出数据层是实现控制、数据信息分流的必要选择,便于数据、资源自成体系,更好地实现资源库管理。事务实现层数据访问层SIP状态数据接口XML组件接口硬件模块服务器系统平台配置SIP服务配置业务逻辑层SIP ServletUA通信接口控制接口SIP通信接口SIP路由指令网络存储服务WEB服务器无线下级SIP转发器,用户终端,网络监控设施终端配置控制数据图1系统架构媒体管理平台实施对网上的基于SIP的流媒体设备进行呼叫连接、控制云台等,需要集成通信接口程序,以便向SIP Servlet发出查询或连接指令,解释处理传回的响应指令。终端中的流媒体源设备包括摄像头、视频网关等,本地源设备、转发器、管理平台等UA要进入SIP路由器体系,源设备需要集成接口程序,以解释指令,SIP服务器可能向其发起交互连接,发送、收集、控制云台命令,必须在路由器的配置文件中进行正确的配置3。流媒体转发器将源设备的媒体中介转发到目标处,流媒体转发器由SIP服务器的指令控制,从源设备处获取流媒体,然后按SIP服务器传来的指令发送到目标。基于当前数据流,特别是多媒体数据流的海量信息,而控制等指令要求快捷传送,各级监控中心和下一级监控中心、终端之间建立虚拟双向双传输通道,所谓虚拟是指完全由软件编程实现,不改变物理连接。控制等信令走控制通道,用来监控管理、使用设备和目标设备之间建立会话并传输控制命令,信令协议具体参见本规范相关部分的规定。数据流通道用来传输视频图像、音频数据,经过压缩编码的音视频流保留原传输协议,对下有兼容。3通信指令设计系统能互访的核心技术有TCP/IP协议,Servlet编程,URI等,与一般Sockets网络编程一致,实现Servlet的前提需要一个地址,特别设计的SIP URI形如jy,其中表示SIP路由的物理位置,可以是域名,也可以是IP地址4。而jy表示该URI的逻辑位置,用于SIP路由的解析,可以根据该URI构造一个树型结构,与前面系统的树状结构一一对应。为对应各级监控中心和终端,SIP URI也可以分为两类。终端是末级功能单元,该单元可以小到某一个智能摄像头,也可以包括接口、控制器、转发器等设备为一个单元,都对应一个SIP URI,通过URI可以完成接收数据、发起呼叫、按需传输以及定址等工作。各级监控中心对应逻辑位置,是SIP URI域名的子集,包含一个区域的所有设备、接口和程序,也可以管理所有客户端。获取URI列表的目的,主要用于上级中心获取下级中心的监控资源,资源包括组、视频点、报警点等,采用逐级请求的方式获取。用SIP MESSAGE方法获取URI列表,消息体的内容为:请求:LIST SIP_URI KSLP/1.0 /其中的SIP_URI为SIP地址,NULL表示该用户所获授权的根地址。应答:URI NAME TYPE STATUS /TYPE为可管理的单元类型,default=DL。系统控制信息传输,采用SIP协议作会话控制,控制命令的传输流程如图2所示,对于逻辑上直接上下的URI,可以不经过SIP服务器的转接。监控资源,路由设备,甲终端设备SIP服务器监控资源,路由设备,乙终端设备发起会话请求SIP应答控制信息传输反馈信息传输拆除会话请求连接传输传输请求拆除图2 控制命令的传输参数查询设置用MESSAGE方法实现,在消息体中参数设置信令。在消息体中自行扩展,加入云台(或其他设备)控制指令,Content-Type为Application/,以云台控制指令定义为例左转控制如下:INFO sip:jy ;SIP/2.0rnContent-Type:Application/JKPTZrnrn;L,Lrn例如:Content-Type: Application/JKECP(ECP:Equipment Contrl Protocol设备控制协议)表示消息体包含的控制信令为YYYY厂商设备配置信令,消息体的内容根据XXXX.cfgXXXX.framework.V0.1和XXXX.cfgXXXX.protocol.V0.2协议来生成。下面是利用MESSAGE方法,查询设备参数,获取通道号的例子:MESSAGE sip channel0192.168.9.169:5090 SIP/2.0From:<sip:root192.168.9.254>tag=7bd91d8-0-13d8-7ad4-31951365-7ad4To:<sip:channel0192.168.9.169:5090>tag=7bd8fl0-0-13e2-7ad4-36f3193-7ad4Call-ID:7bdae18-0-13d8-7ad3-5f5f015d-7ad3192.168.9.109CSeq:2 MESSAGEVia:SIP/2.0/UDP 192.168.9.169:5080; branch=z9hG4bK-7ad6-1dfd4cal-2424f6a9Max-Forwards:70Contact:<sip:root192.169.9.254>Content-Type:Application/JKECPContent-Length:25GET Channel_NO JKECP/0.1SIP/2.0 200 OK再比如,获取远方设备列表的指令流:管理平台UA>SIP服务器à远方的SIP路由器à远端的SIP URI,辅以通信端口号实施终端扩展,对于临时增加监控设备等要求有用。CMD=LISTrn /CMD:命令类型SIPURI=jyrn /SIPURI:远方端的SIP URI,要查询的对象ME=jyrn /ME:本地管理平台的SIP URI,控制中心4结束语设计遵循了标准的联网视频监控系统,符合构成方式、功能、视频传输的需求分析,实现了流媒体传输协议、视频采集和视频传输设备的技术要求,达到了联网视频数据库、视频数据检索规范、联网视频监控系统和视频数据的安全性标准。随着下一代网络的到来,通信行业将会迎来一次新的变革,文章通过对NGN的主要交换协议一SIP进行分析及应用,为以后更多基于NGN的产品研发及应用作了一个尝试。参考文献:1. 陈羽等.NGN中SIP监测系统的研究与实现J.电信工程技术与标准化、2008、8:84-872. 荣玮等.基于网络电视的视频通话方案设计J.电视技术、2010、34(8):60-613. 廖永红,孟治国.双网多媒体可视电话系统安全架构设计J.通信技术、2009、12:50-524. 范广等.NGN集中监测系统SIP解码模块的设计与实现J.半导体技术、2009、34(9):899-902The Instructions Design of the Remote Monitoring System Based on the NGN Meng Zhiguo(1. Department of Electronic & Communication Engineering, GuangDong Industry Technical College, GuangZhou 510300, China)Abstract:The remote multi-stage monitoring system based on the NGN plays up to the amalgamation of the network. Based on SIP protocol and Video gateway decoding technology, this paper designs instruction system which realizes streaming media transmission, video collection and instructions issue for SIP router and all kinds of UA product. In the process of data transmission and control, the system establishes the two-way double transmission channel, which ensures more effectively the different equipment services and network communication by separating instructions resources.Key words:NGN;Remote Monitoring; Instructions Design;基金项目:网络融合下远程数据智能传输的研究及在移动医疗监护中的应用,项目编号:KJ201011(广东轻工职业技术学院自然科学技术基金)作者简介: 孟治国(1970-),男,山西代县人,高级工程师,发表论文十余篇,主要研究方向:电子信息技术。通信地址:广东省广州市新港西路152号实训大楼A403 邮编:510300 E-mail:Mzg168 ,电话:13719483860Editor's note: Judson Jones is a meteorologist, journalist and photographer. He has freelanced with CNN for four years, covering severe weather from tornadoes to typhoons. Follow him on Twitter: jnjonesjr (CNN) - I will always wonder what it was like to huddle around a shortwave radio and through the crackling static from space hear the faint beeps of the world's first satellite - Sputnik. I also missed watching Neil Armstrong step foot on the moon and the first space shuttle take off for the stars. Those events were way before my time.As a kid, I was fascinated with what goes on in the sky, and when NASA pulled the plug on the shuttle program I was heartbroken. Yet the privatized space race has renewed my childhood dreams to reach for the stars.As a meteorologist, I've still seen many important weather and space events, but right now, if you were sitting next to me, you'd hear my foot tapping rapidly under my desk. I'm anxious for the next one: a space capsule hanging from a crane in the New Mexico desert.It's like the set for a George Lucas movie floating to the edge of space.You and I will have the chance to watch a man take a leap into an unimaginable free fall from the edge of space - live.The (lack of) air up there Watch man jump from 96,000 feet Tuesday, I sat at work glued to the live stream of the Red Bull Stratos Mission. I watched the balloons positioned at different altitudes in the sky to test the winds, knowing that if they would just line up in a vertical straight line "we" would be go for launch.I feel this mission was created for me because I am also a journalist and a photographer, but above all I live for taking a leap of faith - the feeling of pushing the envelope into uncharted territory.The guy who is going to do this, Felix Baumgartner, must have that same feeling, at a level I will never reach. However, it did not stop me from feeling his pain when a gust of swirling wind kicked up and twisted the partially filled balloon that would take him to the upper end of our atmosphere. As soon as the 40-acre balloon, with skin no thicker than a dry cleaning bag, scraped the ground I knew it was over.How claustrophobia almost grounded supersonic skydiverWith each twist, you could see the wrinkles of disappointment on the face of the current record holder and "capcom" (capsule communications), Col. Joe Kittinger. He hung his head low in mission control as he told Baumgartner the disappointing news: Mission aborted.The supersonic descent could happen as early as Sunday.The weather plays an important role in this mission. Starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. It will climb higher than the tip of Mount Everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause), he can expect a lot of turbulence.The balloon will slowly drift to the edge of space at 120,000 feet (22.7 miles/36.53 kilometers). Here, "Fearless Felix" will unclip. He will roll back the door.Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform.Below, the Earth becomes the concrete bottom of a swimming pool that he wants to land on, but not too hard. Still, he'll be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. It will be like he is diving into the shallow end.Skydiver preps for the big jumpWhen he jumps, he is expected to reach the speed of sound - 690 mph (1,110 kph) - in less than 40 seconds. Like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him completely.If he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. His team hopes it's not needed. Instead, he plans to deploy his 270-square-foot (25-square-meter) main chute at an altitude of around 5,000 feet (1,524 meters).In order to deploy this chute successfully, he will have to slow to 172 mph (277 kph). He will have a reserve parachute that will open automatically if he loses consciousness at mach speeds.Even if everything goes as planned, it won't. Baumgartner still will free fall at a speed that would cause you and me to pass out, and no parachute is guaranteed to work higher than 25,000 feet (7,620 meters).It might not be the moon, but Kittinger free fell from 102,800 feet in 1960 - at the dawn of an infamous space race that captured the hearts of many. Baumgartner will attempt to break that record, a feat that boggles the mind. This is one of those monumental moments I will always remember, because there is no way I'd miss this.