【文章內(nèi)容簡介】 : 0 PacketMIA: 0 PacketLateArrival: 0 InternalError: 0 Busies: 0 Jitter Values: MinOfPositivesSD: 1 MaxOfPositivesSD: 1 NumOfPositivesSD: 249 SumOfPositivesSD: 249 Sum2PositivesSD: 249 MinOfNegativesSD: 1 MaxOfNegativesSD: 2 NumOfNegativesSD: 238 SumOfNegativesSD: 239 Sum2NegativesSD: 241 MinOfPositivesDS: 1 MaxOfPositivesDS: 1 NumOfPositivesDS: 97 SumOfPositivesDS: 97 Sum2PositivesDS: 97 MinOfNegativesDS: 1 MaxOfNegativesDS: 1 NumOfNegativesDS: 92 SumOfNegativesDS: 92 Sum2NegativesDS: 92 Interarrival jitterout: 0 Interarrival jitterin: 0 One Way Values: NumOfOW: 0 OWMinSD: 0 OWMaxSD: 0 OWSumSD: 0 OWSum2SD: 0 OWMinDS: 0 OWMaxDS: 0 OWSumDS: 0 OWSum2DS: 0 表7：show rtr collectionstatistics的各域的說明 字段說明NumOfRTT 成功的往返次數(shù) RTTSum 全程時間總和 RTTSum2 全程時間平方和 PacketLossSD 源到目的丟失的包 PacketLossDS 目的到源丟失的包PacketOutOfSequence 返回包序列號不正確的數(shù)量PacketMIA 出現(xiàn)丟包，但方向不能確定，這通訊是一個測試流的最后一個包丟了。 PacketLateArrival 在超時之后到達的包的數(shù)量 InternalError 由于其它內(nèi)部錯誤導(dǎo)致作業(yè)不能正常運行的次數(shù) Busies 由于上次運行未完成而導(dǎo)致本次不能運行的次數(shù)＝MinOfPositivesSDMaxOfPositivesSD 源到目的的最小和最大正抖動（單位為MS） NumOfPositivesSD 源到目的正抖動數(shù)量 SumOfPositivesSD 源到目的總的抖動值 Sum2PositivesSD 源到目的正抖動的平方和 MinOfNegativesSDMaxOfNegativesSD 目的到源的最小和最大正抖動（單位為MS） NumOfNegativesSD 目的到源正抖動數(shù)量 SumOfNegativesSD 目的到源總的抖動值 Sum2NegativesSD 目的到源正抖動的平方和 應(yīng)用于VoIP的UDP抖動作業(yè) 這一類UDP抖動作業(yè)是在當前的UDP抖動作業(yè)基礎(chǔ)上的一個增強與擴展，經(jīng)過增強與擴展之后，經(jīng)命令行或MIB配置，可以通過模擬codec來實現(xiàn)對語音質(zhì)量的測試并直接得出語音質(zhì)量評分，(4)T可以支持如下幾種codec: 216。 711 A Law 216。 u Law 216。 命令如下： (config) Rtr 1(configrtr) type jitter destipaddr ipaddress destport portno codec codectype codecinterval value codecsize value codecnumpacket value新的參數(shù)的選項如下表所示：CodectypecodecsizecodecintervalcodecnumpacketsG711ulaw17220 ms1000G711alaw17220 ms1000G729a3220 ms1000VoIP作業(yè)使用ICPIF語音質(zhì)量評價系統(tǒng)事測試MOS值，可以通過命令行和MIB存取活動的測試結(jié)果中的MOS值。這個測試可以從應(yīng)用的角度看出來網(wǎng)絡(luò)性能參數(shù)對VoIP的支持程度。雖然ICPIF/MOS參數(shù)在評價語音質(zhì)量時是非常有用的，但它并沒有包括能夠影響到語音質(zhì)量的所有參數(shù)。更詳細的信息可以參見如下的文檔：IOS (7)T提供了基于單向抖動、丟包情況、延時及MOS/ICPIF語音得分參數(shù)設(shè)置反應(yīng)閾值或發(fā)出SNMP trap的能力，詳細情況可以參見如下鏈接： (7)T下測試通過： logging on rtr 10 type jitter destipaddr destport 16384 codec g711alaw advantagefactor 2 owner admin tag jitterwithvoicescores rtr schedule 10 starttime now rtr reactionconfiguration 10 react mos thresholdtype immediate\ thresholdvalue 490 250 actiontype trapOnly rtr logging traps snmpserver host version 2c public snmpserver enable traps syslog (7)T中的trap的實質(zhì)是syslog到traps的轉(zhuǎn)換，因此需要在命令行配置logging，在以后的版本中將提供純粹的SNMP trap. 下面是相關(guān)Show的結(jié)果 Router show rtr operationalstate 10 Entry number: 10 Modification time: 12:57: UTC Sun Oct 26 2003 Number of operations attempted: 1 Number of operations skipped: 0 Current seconds left in Life: Forever Operational state of entry: Active Last time this entry was reset: Never Connection loss occurred: FALSE Timeout occurred: FALSE Over thresholds occurred: FALSE Latest RTT (milliseconds): 19 Latest operation start time: 12:57: Sun Oct 26 2003 Latest operation return code: OK ! Voice Scores: ICPIF: 20 MOS Score: 3 ! RTT Values: NumOfRTT: 10 RTTAvg: 19 RTTMin: 19 RTTMax: 20 RTTSum: 191 RTTSum2: 3649 Packet Loss Values: PacketLossSD: 0 PacketLossDS: 0 PacketOutOfSequence: 0 PacketMIA: 0 PacketLateArrival: 0 InternalError: 0 Busies: 0 Jitter Values: NumOfJitterSamples: 9 MinOfPositivesSD: 0 MaxOfPositivesSD: 0 NumOfPositivesSD: 0 SumOfPositivesSD: 0 Sum2PositivesSD: 0 MinOfNegativesSD: 0 MaxOfNegativesSD: 0 NumOfNegativesSD: 0 SumOfNegativesSD: 0 Sum2NegativesSD: 0 MinOfPositivesDS: 1 MaxOfPositivesDS: 1 NumOfPositivesDS: 1 SumOfPositivesDS: 1 Sum2PositivesDS: 1 MinOfNegativesDS: 1 MaxOfNegativesDS: 1 NumOfNegativesDS: 1 SumOfNegativesDS: 1 Sum2NegativesDS: 1 Interarrival jitterout: 0 Interarrival jitterin: 0 One Way Values: NumOfOW: 0 OWMinSD: 0 OWMaxSD: 0 OWSumSD: 0 OWSum2SD: 0 OWMinDS: 0 OWMaxDS: 0 OWSumDS: 0 OWSum2DS: 0 Router show rtr collectionstatistics 10 Entry number: 10 Start Time Index: 12:57: UTC Sun Oct 26 2003 Number of successful operations: 60 Number of operations over threshold: 0 Number of failed operations due to a Disconnect: 0 Number of failed operations due to a Timeout: 0 Number of failed operations due to a Busy: 0 Number of failed operations due to a No Connection: 0 Number of failed operations due to an Internal Error: 0 Number of failed operations due to a Sequence Error: 0 Number of failed operations due to a Verify Error: 0 Voice Scores: MinOfICPIF: 2 MaxOfICPIF: 20 MinOfMos: 3 MaxOfMos: 5 RTT Values: NumOfRTT: 600 RTTAvg: 20 RTTMin: 19 RTTMax: 22 RTTSum: 12100 RTTSum2: 244292 Packet Loss Values: PacketLossSD: 0 PacketLossDS: 0 PacketOutOfSequence: 0 PacketMIA: 0 PacketLateArrival: 0 InternalError: 0 Busies: 0 Jitter Values: NumOfJitterSamples: 540 MinOfPositivesSD: 1 MaxOfPositivesSD: 1 NumOfPositivesSD: 26 SumOfPositivesSD: 26 Sum2PositivesSD: 26 MinOfNegativesSD: 1 MaxOfNegativesSD: 1 NumOfNegativesSD: 19 SumOfNegativesSD: 19 Sum2NegativesSD: 19 MinOfPositivesDS: 1 MaxOfPositivesDS: 1 NumOfPositivesDS: 43 SumOfPositivesDS: 43 Sum2PositivesDS: 43 MinOfNegativesDS: 1 MaxOfNegativesDS: 2 NumOfNegativesDS: 43 SumOfNegativesDS: 44 Sum2NegativesDS: 46 Interarrival jitterout: 0 Interarrival jitterin: 0 One Way Values: NumOfOW: 0 OWMinSD: 0 OWMaxSD: 0 OWSumSD: 0 OWSum2SD: 0 OWMinDS: 0 OWMaxDS: 0 OWSumDS: 0 OWSum2DS: 0. ICMP Echo作業(yè)ICMP Echo作業(yè)可以測試Cisco 路由器和IP設(shè)備之間的端到端的響應(yīng)時間，響應(yīng)時間是通過計算ICMP echo請求與響應(yīng)消息的時間差也教育處的。IP SLA通過在IP包中設(shè)置DSCP位，也允許用戶測量QOS的實施情況。 響應(yīng)時間計算 如以前討論的一樣，在計算時，處理延時被最小化并在最終結(jié)果中減去。 圖6：ICMP echo作業(yè)的響應(yīng)時間計算 　ICMP 荷載通過設(shè)置”request size”用戶可以配置ICMP ECHO作業(yè)的有效荷載尺寸，路由器將在定義的數(shù)值之上加上36 Bytes，如定義的requestsize是28Bytes，則實際的ICMP包的大小是64Bytes。 　配置ICMP echo作業(yè)(config)rtr 2(configrtr)type echo protocol ipicmpecho (configrtrecho)requestdatasize 400(configrtrecho)tos 160(config)rtr sch