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SG TCP/IP Analyzer

IP Address: (
Client OS: Search Bot
User Agent: CCBot/2.0 (
Please Read the Analyzer FAQ if the above is not your IP address.

TCP options string = 0204058c0103030201010402
MTU = 1460
MTU is not fully optimized for broadband. Consider increasing your MTU to 1500 for better throughput. If you are using a router, it could be limiting your MTU regardless of Registry settings.
MSS = 1420
Maximum useful data in each packet = 1420, which equals MSS.
Default TCP Receive Window (RWIN) = 66740
RWIN Scaling (RFC1323) = 2 bits (scale factor: 2^2=4)
Unscaled TCP Receive Window = 16685

RWIN is not fully optimized. The unscaled RWIN value is lower than it should be. Also, RWIN being close to and above 65536 does not justify the header overhead of enabling TCP 1323 Options. You might want to use one of the recommended RWIN values below.

RWIN is a multiple of MSS
Other RWIN values that might work well with your current MTU/MSS:
65320  (up to 2 Mbit lines, depending on latency. MSS * 46)
130640 (1-5 Mbit lines, depending on latency. MSS * 46 * 2)
261280 (2-15 Mbit lines, depending on latency. MSS * 46 * 2^2)
522560 (10-30 Mbit lines, depending on latency. MSS * 46 * 2^3)
1045120 (30-100 Mbit lines depending on latency. MSS * 46 * 2^4)

bandwidth * delay product (Note this is not a speed test):

Your current TCP Window limits you to: 2670 kbps (334 KBytes/s) @ 200ms latency
Your current TCP Window limits you to: 1068 kbps (133 KBytes/s) @ 500ms latency
MTU Discovery (RFC1191) = ON
Time to live left = 112 hops
TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00000000 (0)

Share Your Results

Below is a compact version of the results without specific recommendations, useful for sharing your current settings. Feel free to post in our forums with any questions you may have.

Note: Click in text area to highlight. Use CTRL+C to copy results, CTRL+V to paste them.


Optimize Your Connection

The TCP/IP Analyzer results provide packet header information from the TCP 3-way handshake between your computer and our server. The information above can be used to fine-tune TCP/IP settings and optimize your internet connection.
Detailed information on optimizing your network-related settings is available in our Broadband articles and TCP/IP Tweaks Articles.
We have also developed the free TCP Optimizer program to help apply the optimal settings automatically: SG TCP/IP Optimizer

Feel free to ask specific questions about your results in our forums.

81,756,048 connections tested since 2001.03.10
Analyzer version: 1.34 - last updated 2019.06.18

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