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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 = 020405b40103030801010402
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) = 131328
RWIN Scaling (RFC1323) = 8 bits (scale factor: 2^8=256)
Unscaled TCP Receive Window = 513

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:
64240  (up to 2 Mbit lines, depending on latency. MSS * 44)
128480 (1-5 Mbit lines, depending on latency. MSS * 44 * 2)
256960 (2-20 Mbit lines, depending on latency. MSS * 44 * 2^2)
513920 (20-100 Mbit lines, depending on latency. MSS * 44 * 2^3)
1027840 (80+ Mbit lines up to Gigabit connections, depending on latency. MSS * 44 * 2^4)

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

Your current TCP Window limits you to: 525 Mbps (~53 Megabytes/s) @ 200ms latency
Your current TCP Window limits you to: 210 Mbps (~21 Megabytes/s) @ 500ms latency
Note: You can expect up to ~90% of this throughput considering line overhead.
MTU Discovery (RFC1191) = ON
Time to live left = 113 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.

91,803,677 connections tested since 2001.03.10
Analyzer version: 1.36 - last updated 2021.10.23

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