• / 33
  • 下载费用:10 金币  

美国国家标准技术局

关 键 词:
美国国家标准 美国国家标准技术 美国国家标准技术局
资源描述:
NIST NIST WiMAXWiMAX Module Module 徐士欽 Introduction Introduction l美國國家標準技術局(National Institute of Standards and Technology, NIST) l經過NS-2官方網站一連串的相關測試成為 內建模組 lIEEE 802.16e延伸,支援掃描與換手 l我可以用這個模組做些什麼? OverviewOverview Available features Summary of features NOT implemented -WirelessMAN-OFDM physical layer with configurable modulation -Time Division duplexing (TDD) -Management messages to execute network entry (without authentication) -Default scheduler providing round robin uplink allocation to registered Mobile Stations (MSs) according to bandwidth requested -IEEE 802.16e extensions to support scanning and handovers -Fragmentation and reassembly of frames -WirelessMAN-OFDMA -Frequency Division duplexing (FDD) -ARQ (Automatic Repeat Request) -Service Flow and Quality of Service (QoS) scheduling -Periodic ranging and power adjustments Packing -Error Correction Try First ! lThe example “test-be.tcl” in /ns-allinone-2.29/ns-2.29/tcl/wimax 要做什麼? l到底要怎麼用? l跟普通的有什麼不一樣? l來看看TCL吧! 還記得什麼還記得什麼???? l設定WiMAX基本參數 RTG、TTG、、等 l設定PHY為OFDM! l設定涵蓋範圍 l設定Mobile node config (OPT系列),尤其是 MAC! l初始化BS位置,設定node l初始化SS位置,設定與BS相依 l設定DIUC 幾個小問題幾個小問題 l怎麼都沒看到mobile node? lCreate God ? ¡Storing connectivity information of the topology. ¡http://0rz.tw/df3cX lset opt(adhocRouting) DSDV ¡可以不設嗎? ¡有哪些選擇? ¡DSDV、DSR、AODV和TORA 本週小練習本週小練習 l請改寫test-be.tcl使得無法在NAM上顯示所 有定義的mobile node的問題得以解決。 l請至少能顯示10個nodes l相對的,完成此作業的前提是要安裝成功 NIST的module 再深入一點再深入一點 lMAC層模組架構 ¡Mac802_16(Class)繼承NS-2原有的Mac類別,負 責處理封包的傳送與接收 。 lFrame structure ¡Time Division Duplex, TDD ¡Uplink & Downlink lIEEE 802.16e ¡Scanning ¡Handoff MAC module structure 幾個重要的元件幾個重要的元件 lServiceFlowHandler is responsible for handling flow requests/responses. It also stores the list of flows for the node. lThe class PeerNodePeerNode contains information about the peer, such as its connections and status. l l ConnectionManagerConnectionManager contains the list of incoming and outgoing connections. 更多的重要元件 lThe WimaxSchedulerWimaxScheduler abstract class is used to create an interface with the MAC. (SS & BS) l l StatWatchStatWatch and ThroughputWatchThroughputWatch objects for packet and traffic information. The values are used to trigger events MAC802_16 MAC802_16 內容貌似很重要內容貌似很重要! ! 封包資訊都藏在哪裡封包資訊都藏在哪裡? ? l/ns-allinone-2.29/ns- 2.29/wimax/mac802_16.cc HeaderHeader裡的重要資訊裡的重要資訊 lA virtual physical header of type phy_info_t. This structure is used to carry physical information lA generic MAC header of type gen_mac_header_tgen_mac_header_t containing the generic MAC information. SchedulerScheduler lThe class structure allows for specifying different data services namely UGS, rtPS, nrTPS, and Best Effort. The services are specified in the ServiceFlow class. lBS scheduler & SS scheduler. Packet Processing Flow classifier 緊緊相依 相互影響 lMAP:描述頻寬分配後的結果,SS需在指 定的時間傳送或接收資料 l對進入的封包做Service flow 的QoS設置 lBS Scheduler的運作機制 lSS Scheduler的運作機制 QoS & Service Flow lThe framework defines structures to support the implementation of schedulers that make use of the different classes of service. lEach Connection can be associated with a ServiceFlow and corresponding QoS parameters. Service Flow如何被實現 ns-allinone-2.29/ns-2.29/wimax 空歡喜 lQoS尚未被實作,空殼定義 l只有BE被實作 lNO Admission control ! ¡It accepts all the flow request from the MSs. l真遺憾,那我們還能做些什麼?? ¡TCL commands TCL Command lReplace the default service flow handler. lThe parameters are as follows: lDL – Downlink, use UL for Uplink l10000 – Data Rate (byte/s) lBE - Scheduling Type BE/rtPS/nrtPS/ertPS l700 – Datasize (byte) l2 – Period (For UGS traffic) l1 - To indicate if ARQ is enabled or not l0.01 - ARQ Retransmission timer value (s) l8 - ARQ Window size l1 - counter to indicate when ARQ ACKs have to be sent lConfigure the list of flows that must be setup after network entry. mac set-servicehandler FlowHandler [$wl_node_($i) set mac_(0)] setflow DL 10000 BE 700 2 1 0.01 8 1 Schedulers (cont.) l In IEEE 802.16, the BS controls the bandwidth allocation. l The model includes an abstract class, WimaxScheduler, created to easily use different packet schedulers. lThis class already contains two implementations, an SSscheduler for SSs and a BSscheduler for BSs. 彈性的架構設計 ns-allinone-2.29/ns-2.29/wimax/scheduling 我想自己做scheduler! linit (): initialize the scheduler. lprocess (Packet *): ¡This method is used to process packets received by the scheduler (such as synchronization messages). lstart_ulsubframe (): ¡code to be executed at the beginning of a new uplink subframe. lstart_dlsubframe (): ¡ code to be executed at the beginning of a new downlink subframe. BS Scheduler TCL commandBS Scheduler TCL command lset scheduler [new WimaxScheduler/BS] ¡Creates a packet scheduler for BS. l$scheduler set-contention-size $size ¡Set the number of contention slots to be allocated for initial ranging and bandwidth requests in each frame. lWimaxScheduler/BS set dlratio_ 0.3 ¡Indicates 30% of the frame is for downlink and 70% is for uplink. SS Scheduler TCL commandSS Scheduler TCL command lset scheduler [new WimaxScheduler/SS] ¡Creates a packet scheduler for SS. DIUC / UIUC Profile nameProfile nameModulationModulation DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_BPSK_1_2 DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_QPSK_1_2 DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_QPSK_3_4 DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_16QAM_1_2 DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_16QAM_3_4 DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_64QAM_2_3 DIUC_PROFILE_1, UIUC_PROFILE_1OFDM_64QAM_3_4 怎麼設定調變怎麼設定調變 l[$SSWithWiMax set mac_(0)] set-diuc 7 ¡The user can select the burst profile to use [1-7] by TCL. lNote: By default, the profile (modulation) is the same for BOTH downlink and uplink for communication between an SS and a BS. 設定設定schedulerscheduler與節點的連結與節點的連結 l# Add scheduler l[$nodeWithWiMax set mac_(0)] set-scheduler $scheduler D/UIUC會不會被調整? lCurrently there is no algorithm implemented to make use of the ranging capabilities. It is used to add additional latency to the network entry. Periodic ranging and CDMA request are also not implemented. 謝謝 l還有問題嗎?
展开阅读全文
  麦档网所有资源均是用户自行上传分享,仅供网友学习交流,未经上传用户书面授权,请勿作他用。
0条评论

还可以输入200字符

暂无评论,赶快抢占沙发吧。

关于本文
本文标题:美国国家标准技术局
链接地址:https://www.maidoc.com/p-15670062.html
关于我们 - 网站声明 - 网站地图 - 资源地图 - 友情链接 - 网站客服 - 联系我们

[email protected] 2018-2020 maidoc.com版权所有  文库上传用户QQ群:3303921 

麦档网为“文档C2C模式”,即用户上传的文档所得金币直接给(下载)用户,本站只是中间服务平台,本站所有文档下载所得的金币归上传人(含作者)所有。
备案号:蜀ICP备17040478号-3  
川公网安备:51019002001290号 


收起
展开