具体资料:
ptimized Link State Routing Protocol
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The Optimized Link State Routing Protocol (OLSR)[1] is an IP routing protocol which is optimized for mobile ad-hoc networks but can also be used on other wireless ad-hoc networks. OLSR is a proactive link-state routing protocol which uses Hello and Topology Control (TC) messages to discover and then disseminate link state information throughout the mobile ad-hoc network. Individual nodes use this topology information to compute next hop destinations for all nodes in the network using shortest hop forwarding paths.
Contents
[hide]
* 1 Features specific to OLSR
* 2 Benefits
* 3 Criticisms
* 4 Messages
o 4.1 Hello
o 4.2 TC (Topology Control)
* 5 Other approaches
* 6 OLSR version 2
* 7 Implementations
* 8 External links
* 9 References
[edit] Features specific to OLSR
Link-state routing protocols such as OSPF and IS-IS elect a designated router on every link in order to perform flooding of topology information. In wireless ad-hoc networks, there is different notion of a link, packets can and do go out the same interfacehence, a different approach is needed in order to optimize the flooding process. Using Hello messages the OLSR protocol at each node discovers 2-hop neighbor information and performs a distributed election of a set of multipoint distribution relays (MPRs). Nodes select MPRs such that there exists a path to each of its 2-hop neighbors via a node selected as an MPR. These MPR nodes then source and forward TC messages which contain the MPR selectors. This functioning of MPRs makes OLSR unique from other link state routing protocols in a few different ways: The forwarding path for TC messages is not shared among all nodes but varies depending on the source, only a subset of nodes source link state information, not all links of a node are advertised but only those which represent MPR selections.
Since link-state routing requires the topology database to be synchronized across the network, OSPF and IS-IS perform topology flooding using a reliable algorithm. Such an algorithm is very difficult to design for ad-hoc wireless networks, so OLSR doesn't bother with reliabilityit simply floods topology data often enough to make sure that the database does not remain unsynchronized for extended periods of time.
[edit] Benefits
Being a proactive protocol, routes to all destinations within the network are known and maintained before use. Having the routes available within the standard routing table can be useful for some systems and network applications as there is no route discovery delay associated with finding a new route.
The routing overhead generated, while generally greater than that of a reactive protocol, does not increase with the number of routes being used.
Default and network routes can be injected into the system by HNA messages allowing for connection to the internet or other networks within the OLSR MANET cloud. Network routes are something which reactive protocols do not currently execute well.
Timeout values and validity information is contained within the messages conveying information allowing for differing timer values to be used at differing nodes.
[edit] Criticisms
The original definition of OLSR does not include any provisions for sensing of link qualityit simply assumes that a link is up if a number of hello packets have been received recently. This assumes that links are bi-modal (either working or failed), which is not necessarily the case on wireless networks, where links often exhibit intermediate rates of packet loss. Implementations such as the open source OLSRd (commonly used on Linux-based mesh routers) have been extended (as of v. 0.4.8) with link quality sensing. This is sometimes called "fish-eye" or Radio-Aware OLSR or RA-OLSR and is one of the two protocols included in the 802.11s draft standard. It was influenced by the HSLS protocol.
Being a proactive protocol, OLSR uses power and network resources in order to propagate data about possibly unused routes. While this is not a problem for wired access points and laptops, it makes OLSR unsuitable for sensor networks which try to sleep most of the time. For small scale wired access points with low CPU power, the open source OLSRd project showed that large scale mesh networks can run with OLSRd on thousands of nodes with very little CPU power on 200MHz embedded devices.
Being a link-state protocol, OLSR requires a reasonably large amount of bandwidth and CPU power to compute optimal paths in the network. In the typical networks where OLSR is used (which rarely exceed a few hundreds of nodes), this does not appear to be a problem.
By only using MPRs to flood topology information, OLSR removes some of the redundancy of the flooding process, which may be a problem in networks with large packet loss rates[citation needed] - however the MPR mechanism is self-pruning (which means that in case of packet losses, some nodes which would not have retransmitted a packet, may do so).
[edit] Messages
OLSR makes use of "Hello" messages to find its one hop neighbors and its two hop neighbors through their responses. The sender can then select its multipoint relays (MPR) based on the one hop node which offer the best routes to the two hop nodes. Each node has also an MPR selector set which enumerates nodes that have selected it as an MPR node. OLSR uses Topology Control (TC) messages along with MPR forwarding to disseminate neighbor information throughout the network. Host Network Address (HNA) messages are used by OLSR to disseminate network route advertisements in the same way TC messages advertise host routes.
[edit] Hello
Image:olsr-hello-packet.png
[edit] TC (Topology Control)
Image:Olsr-tc-packet.png
[edit] Other approaches
The problem of routing in ad-hoc wireless networks is actively being researched, and OLSR is but one of several proposed solutions. To many, it is not clear whether a whole new protocol is needed, or whether OSPF could be extended with support for wireless interfaces[2][3].
In bandwidth- and power-starved environments, it is interesting to keep the network silent when there is no traffic to be routed. Reactive routing protocols do not maintain routes, but build them on demand. As link-state protocols require database synchronisation, such protocols typically use the distance vector approach, as in AODV and DSDV, or more ad-hoc approaches that do not necessarily build optimal paths, such as Dynamic Source Routing.
For more information see the list of ad-hoc routing protocols.
[edit] OLSR version 2
OLSRv2 is currently being developed within the IETF. It maintains many of the key features of the original including MPR selection and dissemination. Key differences are the flexibility and modular design using shared components: packet format packetbb, and neighborhood discovery protocol NHDP. These components are being designed to be common among next generation IETF MANET protocols. Differences in the handling of multiple address and interface enabled nodes is also present between OLSR and OLSRv2.
[edit] Implementations
* OLSR.ORG - Downloadable code for OLSR on GNU/Linux, Windows, Mac OS X, FreeBSD and NetBSD systems. Features a great deal of documentation, including an informative survey of related work.
* NRL-OLSR - Open source code of NRL-OLSR. Works on Windows, MacOS, Linux, and various embedded PDA systems such as Arm/Zaurus and PocketPC as well as simulation environments ns2 and OPNET., http://cs.itd.nrl.navy.mil/focus/
* SOURCEFORGE.NET-OLSR - Created by MOVIQUITY and based on studies within the project Workpad, it offers a code in C# to deploy a MANET (Ad-Hoc, Meshnet) with protocol OLSR. Developed for WM 6, Win XP and can be adapted to other platforms using NET Framework and Compact http://sourceforge.net/projects/wmolsr/
[edit] External links
* IETF Home Page The Internet Engineering Task Force standards body
* olsr.funkfeuer.at currently advancing the olsr.org implementation to improve scalability
* Optimized Link State Routing which includes this Flash Demo.
* Freifunk Firmware (English language page) - a firmware based on OpenWRT that uses OLSR, designed to build mesh networks out of wireless access points, e.g. LinksysWRT54G's
* Pyramid Linux - an embedded distro for embedded x86 boards with OLSR, web interface, etc. Primarily used in Community Networks.
* NRL's Networks and Communication Systems Branch - includes project information and open source networking tools and software developed by the U.S. Naval Research Lab.
[edit] References
1. ^ RFC 3626 http://www.ietf.org/rfc/rfc3626.txt
2. ^ Extensions to OSPF to Support Mobile Ad Hoc Networking, Madhavi Chandra, Abhay Roy, 21-Sep-08, draft-ietf-ospf-manet-or-01.txt
20到1023号端口
31024到49151号端口
449152到65535号端口
用50000-65535，从这个范围内随便选
常用端口描述
20 /tcp FTP数据
21 /tcp FTP控制 文件传输协议
22 /tcp SSH 安全登录、文件传送(SCP)和端口重定向
23 /tcp Telnet 不安全的文本传送
25 /tcp SMTP 简单邮件传输协议(Simple Mail Transfer Protocol)(E-mail)
53 /tcp 域名服务器
69 /udp TFTP 日常文件传输协议(Trivial File Transfer Protocol)
8080 /tcp WWW (HTTP超文本传送协议)
110 /tcp POP3 邮局协议(Post Office Protocol)(E-mail)
161 /udp SNMP 简单网络管理协议(Simple Network Management Protocol)
443 /tcp HTTPS 经过加密的HTTP(used for securely transferring web pages)
端口描述状态
0/TCP,UDP保留端口；不使用（若发送过程不准备接受回复消息，则可以作为源端口）官方
1/TCP,UDP TCPMUX （传输控制协议端口服务多路开关选择器）官方
5/TCP,UDP RJE （远程作业登录）官方
7/TCP,UDP ECHO （回显）协议官方
9/TCP,UDP DISCARD （丢弃）协议官方
11/TCP,UDP SYSTAT 协议官方
13/TCP,UDP DAYTIME协议 官方
15/TCP,UDP NETSTAT 协议官方
17/TCP,UDP QOTD （Quote of the Day，每日引用）协议官方
18/TCP,UDP消息发送协议官方
19/TCP,UDP CHARGEN （字符发生器）协议官方
20/TCP,UDP 文件传输协议 - 默认数据端口官方
21/TCP,UDP 文件传输协议 - 控制端口官方
22/TCP,UDP SSH (Secure Shell) - 远程登录协议，用于安全登录 文件传输 （ SCP ， SFTP ）及端口重新定向官方
23/TCP,UDP Telnet 终端仿真协议 - 未加密文本通信官方
25/TCP,UDP SMTP（简单邮件传输协议） - 用于邮件服务器间的 电子邮件 传递官方
26/TCP,UDP RSFTP - 一个简单的类似FTP的协议非官方
35/TCP,UDP QMS Magicolor 2 printer 非官方
37/TCP,UDP TIME时间协议 官方
39/TCP,UDP Resource Location Protocol（资源定位协议） 官方
41/TCP,UDP图形官方
42/TCP,UDPHost Name Server（主机名服务）官方
42/TCP,UDP WINS （WINS主机名服务）非官方
43/TCP WHOIS 协议官方
49/TCP,UDP TACACS 登录主机协议官方
53/TCP,UDP DNS （域名服务系统）官方
56/TCP,UDP远程访问协议官方
57/TCPMTP，邮件传输协议
67/UDP BOOTP （BootStrap协议）服务；同时用于 动态主机设置协议 官方
68/UDP BOOTP 客户端；同时用于 动态主机设定协议 官方
69/UDP TFTP （小型文件传输协议）官方
70/TCP Gopher信息检索协议 官方
79/TCP Finger 协议官方
80/TCP HTTP （超文本传输协议）- 用于传输网页官方
81/TCP HTTP 预备（超文本传输协议）官方
81/TCP Torpark - Onion routing ORport非官方
82/UDP Torpark - 控制端口非官方
88/TCP Kerberos - 认证代理官方
101/TCP主机名
102/TCPISO-TSAP 协议
107/TCP远程 Telnet 协议
109/TCPPOP（Post Office Protocol），“邮局协议”，第2版
110/TCP POP3 （“邮局协议”，第3版）- 用于接收 电子邮件 官方
111/TCP,UDPSun协议官方
113/TCP ident - 旧的服务器身份识别系统，仍然被 IRC 服务器用来认证它的用户官方
115/TCPSFTP, 简单文件传输协议
117/TCPUUCP-PATH
118/TCP,UDP SQL 服务官方
119/TCP 网络新闻传输协议 - 用来收取新闻组的消息官方
123/UDP NTP (Network Time Protocol) - 用于时间同步官方
135/TCP,UDPEPMAP (End Point Mapper) / Microsoft RPC Locator Service官方
137/TCP,UDP NetBIOS NetBIOS Name Service官方
138/TCP,UDP NetBIOS NetBIOS Datagram Service官方
139/TCP,UDP NetBIOS NetBIOS Session Service官方
143/TCP,UDP IMAP4 (Internet Message Access Protocol 4) - used for retrieving E-mail s官方
152/TCP,UDPBFTP, Background File Transfer Program
153/TCP,UDPSGMP, Simple Gateway Monitoring Protocol
156/TCP,UDPSQL服务官方
158/TCP,UDPDMSP, Distributed Mail Service Protocol
161/TCP,UDP SNMP (Simple Network Management Protocol)官方
162/TCP,UDPSNMPTRAP官方
170/TCPPrint-srv
179/TCP BGP (Border Gateway Protocol)官方
194/TCP IRC （互联网中继聊天）官方
201/TCP,UDPAppleTalk Routing Maintenance
209/TCP,UDPQuick Mail传输协议
213/TCP,UDP IPX 官方
218/TCP,UDPMPP，信息发布协议
220/TCP,UDP IMAP ，交互邮件访问协议第3版
259/TCP,UDPESRO, Efficient Short Remote Operations
264/TCP,UDP BGMP ，Border Gateway Multicast Protocol
308/TCPNovastor Online Backup官方
311/TCPApple Server-Admin-Tool, Workgroup-Manager-Tool
318/TCP,UDPTSP， 时间戳协议 （ 英语 ： Time Stamp Protocol ）
323/TCP,UDPIMMP, Internet Message Mapping Protocol
383/TCP,UDPHP OpenView HTTPs Operations Agent
366/TCP,UDPSMTP, Simple Mail Transfer Protocol. ODMR, On-Demand Mail Relay
369/TCP,UDPRpc2portmap官方
371/TCP,UDPClearCase albd官方
384/TCP,UDP一个远程网络服务器系统
387/TCP,UDPAURP, AppleTalk Update-based Routing Protocol
389/TCP,UDP 轻型目录访问协议 官方
401/TCP,UDP UPS Uninterruptible Power Supply官方
411/TCP Direct Connect Hub port非官方
412/TCP Direct Connect Client-To-Client port非官方
427/TCP,UDP SLP (Service Location Protocol)官方
443/TCP HTTPS - HTTP over TLS/ SSL （加密传输）官方
444/TCP,UDP SNPP ，Simple Network Paging Protocol
445/TCPMicrosoft-DS ( Active Directory ，Windows shares, Sasser worm ，Agobot, Zobotworm)官方
445/UDPMicrosoft-DS SMB file sharing官方
464/TCP,UDPKerberos Change/Set password官方
465/TCPCisco protocol官方
465/TCP SMTP over SSL 非官方
475/TCPtcpnethaspsrv ( Hasp services, TCP/IP version)官方
497/TCP dantz backup service官方
500/TCP,UDP ISAKMP ，IKE-Internet Key Exchange官方
502/TCP,UDP Modbus ，Protocol
512/TCPexec, Remote Process Execution
512/UDPcomsat, together with biff ：notifies users of new c.q. yet unread e-mail
513/TCP登陆
513/UDPWho
514/TCP rsh protocol - used to execute non-interactive commandline commands on a remote system and see the screen return
514/UDP syslog protocol - used for system logging官方
515/TCP Line Printer Daemon protocol - used in LPD printer servers
517/UDPTalk
518/UDPNTalk
520/TCPefs
520/UDPRouting - RIP 官方
513/UDPRouter
524/TCP,UDP NCP (NetWare Core Protocol) is used for a variety things such as access to primary NetWare server resources, Time Synchronization, etc.官方
525/UDPTimed，Timeserver
530/TCP,UDP 远程过程调用 官方
531/TCP,UDPAOL Instant Messenger, IRC非官方
532/TCPnetnews
533/UDPnetwall, For Emergency Broadcasts
540/TCP UUCP (Unix-to-Unix Copy Protocol)官方
542/TCP,UDP commerce (Commerce Applications)官方
543/TCPklogin, Kerberos login
544/TCPkshell, Kerberos Remote shell
546/TCP,UDPDHCPv6 客户端
547/TCP,UDPDHCPv6 服务器
548/TCPAFP ( Apple Filing Protocol )
550/UDPnew-rwho, new-who
554/TCP,UDP RTSP (Real Time Streaming Protocol)官方
556/TCPRemotefs, rfs, rfs_server
560/UDPrmonitor, Remote Monitor
561/UDPmonitor
563/TCP,UDP NNTP protocol over TLS/SSL (NNTPS)官方
587/TCPemail message submission（ SMTP ） ( RFC 2476 )官方
591/TCP FileMaker 6.0 （及之后版本）网络共享（HTTP的替代，见80端口）官方
593/TCP,UDPHTTP RPC Ep Map（RPC over HTTP, often used by DCOM services and Microsoft Exchange Server ）官方
604/TCPTUNNEL
631/TCP,UDP 互联网打印协议
636/TCP,UDP LDAP over SSL （加密传输，也被称为LDAPS）官方
639/TCP,UDPMSDP, Multicast Source Discovery Protocol
646/TCPLDP, Label Distribution Protocol
647/TCPDHCP Failover Protocol
648/TCPRRP, Registry Registrar Protocol
652/TCPDTCP, Dynamic Tunnel Configuration Protocol
654/UDPAODV, Ad hoc On-Demand Distance Vector
665/TCPsun-dr, Remote Dynamic Reconfiguration非官方
666/UDP 毁灭战士 ，电脑平台上的一系列 第一人称射击游戏 。
674/TCPACAP, Application Configuration Access Protocol
691/TCPMS Exchange Routing官方
692/TCPHyperwave-ISP
694/UDPLinux-HA High availability Heartbeat port非官方
695/TCPIEEE-MMS-SSL
698/UDPOLSR, Optimized Link State Routing
699/TCPAccess Network
700/TCPEPP, Extensible Provisioning Protocol
701/TCPLMP, Link Management Protocol.
702/TCPIRIS over BEEP
706/TCPSILC, Secure Internet Live Conferencing
711/TCPTDP, Tag Distribution Protocol
712/TCPTBRPF, Topology Broadcast based on Reverse-Path Forwarding
720/TCPSMQP, Simple Message Queue Protocol
749/TCP, UDPkerberos-adm, Kerberos administration
750/UDPKerberos version IV
782/TCP Conserver serial-console management server
829/TCPCMP (Certificate Management Protocol)
860/TCP iSCSI
873/TCP rsync File synchronisation protocol官方
901/TCP Samba Web Administration Tool (SWAT)非官方
902 VMware 服务器控制台 [2] 非官方
904 VMware 服务器替代（如果902端口已被占用）非官方
911/TCP Network Console on Acid (NCA) - local tty redirection over OpenSSH
981/TCP SofaWare Technologies Remote HTTPS management for firewall devices running embedded Checkpoint Firewall-1 software非官方
989/TCP,UDP FTP Protocol (data) over TLS/SSL官方
990/TCP,UDPFTP Protocol (control) over TLS/SSL官方
991/TCP,UDPNAS (Netnews Admin System)
992/TCP,UDPTelnet protocol over TLS/SSL官方
993/TCP IMAP4 over SSL (encrypted transmission)官方
995/TCP POP3 over SSL (encrypted transmission)官方
空间移动网（SMN）
推进当前空间网和近地网的发展
集群通信网络是无人机编队飞行的核心子系统
2.2 通信网络平台设计
10架有人机、110架无人机（本文以3架四旋翼无人机为通信载体）
2.2.1 无人机系统设计
2.2.2 无线通信
- 路由协议模拟分析（TDMA >CSMA）
- MAC协议模拟分析（OLSR >AODV）
反应式路由协议
基于Linux *** 作系统进行开发，利用Qt编译环境设计上位机图形化 *** 控界面
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