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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 = 020405860103030201010402
MTU = 1454
MTU sometimes used in PPPoA applications. If not, 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 = 1414
Maximum useful data in each packet = 1414, which equals MSS.
Default TCP Receive Window (RWIN) = 66456
RWIN Scaling (RFC1323) = 2 bits (scale factor: 2^2=4)
Unscaled TCP Receive Window = 16614

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 not multiple of MSS. If your OS supports setting RWIN directly, consider changing it to a multiple of MSS for optimum performance.
Other RWIN values that might work well with your current MTU/MSS:
65044  (up to 2 Mbit lines, depending on latency. MSS * 46)
130088 (1-5 Mbit lines, depending on latency. MSS * 46 * 2)
260176 (2-15 Mbit lines, depending on latency. MSS * 46 * 2^2)
520352 (10-30 Mbit lines, depending on latency. MSS * 46 * 2^3)
1040704 (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: 2658 kbps (332 KBytes/s) @ 200ms latency
Your current TCP Window limits you to: 1063 kbps (133 KBytes/s) @ 500ms latency
MTU Discovery (RFC1191) = ON
Time to live left = 107 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.

80,099,037 connections tested since 2001.03.10
Analyzer version: 1.32 - last updated 2018.04.20

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