TCP properties for IP = xxxxxxxxxxx()
Browser/OS = Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6) Gecko/20040113
Notes: Read the Analyzer FAQ if the above is not your IP address.
TCP options string = 020405b401010402
MTU = 1500
MTU is fully optimized for broadband.
MSS = 1460
Maximum useful data in each packet = 1460, which equals MSS.
Default TCP Receive Window (RWIN) = 65535
RWIN Scaling (RFC1323) = 0 bits
Unscaled TCP Receive Window = 65535
Note: TCP 1323 Options need to be enabled for RWIN over 2^16 (65535). Windows 9x might also need the MS Vtcp386 fix.
For optimum performance, consider changing RWIN to a multiple of MSS.
Other values for RWIN that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)
bandwidth * delay product (Note this is not a speed test):
Your TCP Window limits you to: 2621.4 Kbps (327.675 KBytes/s) @ 200ms
Your TCP Window limits you to: 1048.56 Kbps (131.07 KBytes/s) @ 500ms
MTU Discovery (RFC1191) = ON
Time to live left = 116 hops
TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00100000 (32)
Precedence (priority) = 001 (priority)
Delay = 0 (normal delay)
Throughput = 0 (normal throughput)
------ Web100 Detailed Analysis ------
Cable modem/DSL/T1 link found.
Link set to Full Duplex mode
No network congestion discovered.
Good network cable(s) found
Normal duplex operation found.
Web100 reports the Round trip time = 105.53 msec; the Packet size = 1460 Bytes; and
No packet loss - but packets arrived out-of-order 11.58% of the time
This connection is receiver limited 88.62% of the time.
This connection is network limited 11.35% of the time.
Web100 reports TCP negotiated the optional Performance Settings to:
RFC 2018 Selective Acknowledgment: ON
RFC 896 Nagle Algorithm: ON
RFC 3168 Explicit Congestion Notification: OFF
RFC 1323 Time Stamping: OFF
RFC 1323 Window Scaling: OFF
Packet size is preserved End-to-End
Server IP addresses are preserved End-to-End
Information: Network Address Translation (NAT) box is modifying the Client's IP address
Server says [xxxxxxxxxx] but Client says [xxxxxxxx
WEB100 Kernel Variables:
Client: localhost/127.0.0.1
AckPktsIn: 1649
AckPktsOut: 0
BytesRetrans: 0
CongAvoid: 0
CongestionOverCount: 0
CongestionSignals: 0
CountRTT: 1458
CurCwnd: 65700
CurMSS: 1460
CurRTO: 330
CurRwinRcvd: 65535
CurRwinSent: 16304
CurSsthresh: 2147483647
DSACKDups: 0
DataBytesIn: 0
DataBytesOut: 5758240
DataPktsIn: 0
DataPktsOut: 3944
DupAcksIn: 191
ECNEnabled: 0
FastRetran: 0
MaxCwnd: 65700
MaxMSS: 1460
MaxRTO: 360
MaxRTT: 200
MaxRwinRcvd: 65535
MaxRwinSent: 16304
MaxSsthresh: 0
MinMSS: 1460
MinRTO: 300
MinRTT: 90
MinRwinRcvd: 65535
MinRwinSent: 16304
NagleEnabled: 1
OtherReductions: 0
PktsIn: 1649
PktsOut: 3944
PktsRetrans: 0
X_Rcvbuf: 103424
RcvWinScale: 2147483647
SACKEnabled: 3
SACKsRcvd: 0
SendStall: 0
SlowStart: 43
SampleRTT: 100
SmoothedRTT: 100
X_Sndbuf: 103424
SndWinScale: 2147483647
SndLimTimeRwin: 8904910
SndLimTimeCwnd: 1140432
SndLimTimeSender: 2588
SndLimTransRwin: 1
SndLimTransCwnd: 1
SndLimTransSender: 1
SndLimBytesRwin: 5524640
SndLimBytesCwnd: 233600
SndLimBytesSender: 0
SubsequentTimeouts: 0
SumRTT: 153870
Timeouts: 0
TimestampsEnabled: 0
WinScaleRcvd: 2147483647
WinScaleSent: 2147483647
DupAcksOut: 0
StartTimeUsec: 314675
Duration: 10050072
c2sData: 2
c2sAck: 2
s2cData: 9
s2cAck: 3
half_duplex: 0
link: 100
congestion: 0
bad_cable: 0
mismatch: 0
spd: 0.00
bw: 105.55
loss: 0.000001000
avgrtt: 105.53
waitsec: 0.00
timesec: 10.00
order: 0.1158
rwintime: 0.8862
sendtime: 0.0003
cwndtime: 0.1135
rwin: 0.5000
swin: 0.7891
cwin: 0.5013
rttsec: 0.105535
Sndbuf: 103424
aspd: 12.78382
Checking for mismatch on uplink
(speed > 50 [0>50], (xmitspeed < 5) [0.37<5]
(rwintime > .9) [0.88>.9], (loss < .01) [1.0E<.01]
Checking for excessive errors condition
(loss/sec > .15) [1.0E>.15], (cwndtime > .6) [0.11>.6],
(loss < .01) [1.0E<.01], (MaxSsthresh > 0) [0>0]
Checking for 10 Mbps link
(speed < 9.5) [0<9.5], (speed > 3.0) [0>3.0]
(xmitspeed < 9.5) [0.37<9.5] (loss < .01) [1.0E<.01], (mylink > 0) [3.0>0]
Checking for Wireless link
(sendtime = 0) [3.0E=0], (speed < 5) [0<5]
(Estimate > 50 [105.55>50], (Rwintime > 90) [0.88>.90]
(RwinTrans/CwndTrans = 1) [1/1=1], (mylink > 0) [3.0>0]
Checking for DSL/Cable Modem link
(speed < 2) [0<2], (SndLimTransSender = 0) [1=0]
(SendTime = 0) [3.0E-4=0], (mylink > 0) [3.0>0]
Checking for half-duplex condition
(rwintime > .95) [0.88>.95], (RwinTrans/sec > 30) [0.1>30],
(SenderTrans/sec > 30) [0.1>30], OR (mylink <= 10) [3.0<=10]
Checking for congestion
(cwndtime > .02) [0.11>.02], (mismatch = 0) [0=0]
(MaxSsthresh > 0) [0>0]
estimate = 105.55 based on packet size = 11Kbits, RTT = 105.53msec, and loss = 1.0E-6
The theoretical network limit is 105.55 Mbps
The NDT server has a 101.0 KByte buffer which limits the throughput to 7.47 Mbps
Your PC/Workstation has a 63.0 KByte buffer which limits the throughput to 4.73 Mbps
The network based flow control limits the throughput to 4.75 Mbps
Client Data reports link is 'T1', Client Acks report link is 'T1'
Server Data reports link is '10 Gig', Server Acks report link is 'Ethernet'
Reliability = 0 (normal reliability)
Cost = 0 (normal cost)
Check bit = 0 (correct, 8th checking bit must be zero)
DiffServ (RFC 2474) = CS1 001000 ( - class 1 (RFC 2474). Similar forwarding behavior to the ToS Precedence field.
