双节点网络中数据报RTT交替波动问题分析求助

我构建了一个双节点网络，编写了名为sensor的代理，让节点A向节点B连续发送数据报5分钟，每两个数据报间隔10秒。模拟完成后，我通过生成的trace.json文件提取数据，绘制每个数据报的RTT（往返时延）图表。图表显示，每个交替的数据报存在明显的时延差异，且交替数据报的时延更低。我无法理解在简单双节点网络中为何会出现这种情况，特此求助。

数据分析代码 #

import json as js
import matplotlib.pyplot as plt

f = open('trace1.json',"r")
data = f.read()
obj = js.loads(data)
list1 = obj['events']
flag = False
bias = 0

for j in range(len(list1)):
    eventobj = list1[j]
    list2 = eventobj['events']
    Dict = {}
    timeList = []
    T = 0
    R = 0
    for i in range(len(list2)):
        if(flag == False):
            bias = list2[0].get('time')
        st = list2[i].get("stimulus")
        if(st['sender'] == 'phy' and st['recipient'] == 'phy'):
            if st['messageID'] in Dict:
                if "response" in list2[i]:                       
                    res = list2[i].get("response")
                    if(res['clazz'] != 'org.arl.unet.phy.BadFrameNtf' and res['clazz'] == 'org.arl.unet.phy.RxFrameNtf'):
                        time1 = Dict[st['messageID']]
                        
                        time2 = list2[i].get("time")
                        diff = abs(time1 - time2)
                        timeList.append([(time1 - bias)/1000,diff/1000])
                        R = R+1
            else:
                if "response" in list2[i]:
                    res = list2[i].get("response")
                    if (res['clazz'] == 'org.arl.unet.phy.TxFrameNtf' and st['clazz'] == 'org.arl.unet.sim.HalfDuplexModem$TX'):
                        Dict[st['messageID']]=(list2[i].get("time"))
                        T = T+1
print(timeList)

x = []
y = []

for i in timeList:
    x.append(i[0])
    y.append(i[1])

plt.plot(x,y)
plt.xlim(0,400)
plt.ylim(0.8,1.2)
plt.xlabel('Timeline in seconds')
plt.ylabel('delay in seconds')

plt.show()

RTT时延图表 #

内容的提问来源于stack exchange，提问作者PrajwalB