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We want to shout it out...
5th Januari 2013
We are here! LetMeCheck.it is your buddy on the web to help test and check common IP functions.
It used to work provided you not upset it by mentioning IPv6. And when it worked it was incredibly useful.
Does anyone know if there’s an alternative similar tool?
TCP options = 020405b4010303060101080a359068bd0000000004020000
MTU = 1500
MTU is fully optimized for broadband.
MSS = 1460
Maximum useful data in each packet = 1448, which is less than MSS because of Timestamps, or other TCP/IP options used.
Default TCP Receive Window (RWIN) = 131712
RWIN Scaling (RFC1323) = 6 bits (scale factor: 2^6=64)
Unscaled TCP Receive Window = 2058
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: 527 Mbps (~53 Megabytes/s) @ 200ms latency
Your current TCP Window limits you to: 211 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 = 53 hops
TTL value is ok.
Timestamps (RFC1323) = ON
Note: Timestamps add 12 bytes to the TCP header of each packet, reducing the space available for useful data.
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00000000 (0)
The site letmecheck.it is still alive but I get this warning message from Firefox..
Just found another site that reports MTU. Albeit also one that is actually maintained.
https://browserleaks.com/ip
I wonder how that DNS leak test works, as it found all the DNS servers for WAN links I have established but I'm not using any of them as I have full resolution on the router.
Test Results Found 7 Servers, 1 ISP, 1 Location
Your DNS Servers
IP Address : ISP : Location :
172.70.88.95 Cloudflare, Inc. United Kingdom, London
172.70.88.147 Cloudflare, Inc. United Kingdom, London
172.70.161.7 Cloudflare, Inc. United Kingdom, London
172.70.161.35 Cloudflare, Inc. United Kingdom, London
2400:cb00:373:1024::ac46:a107 Cloudflare, Inc. United Kingdom, London
2400:cb00:373:1024::ac46:a123 Cloudflare, Inc. United Kingdom, London
2400:cb00:377:1024::ac46:585f Cloudflare, Inc. United Kingdom, London
Test Results Found 7 Servers, 1 ISP, 2 LocationsWhich is pretty strange as I left A&A ages ago and am now with Zen!
Your DNS Servers
IP Address : ISP : Location :
90.155.53.33 Andrews & Arnold Ltd United Kingdom, London
90.155.53.34 Andrews & Arnold Ltd United Kingdom, London
90.155.62.53 Andrews & Arnold Ltd United Kingdom, Bracknell
90.155.62.54 Andrews & Arnold Ltd United Kingdom, Bracknell
2001:8b0:0:53::33 Andrews & Arnold Ltd United Kingdom, Bracknell
2001:8b0:0:62::53 Andrews & Arnold Ltd United Kingdom, Bracknell
2001:8b0:0:62::54 Andrews & Arnold Ltd United Kingdom, Bracknell
DNS Servers . . . . . . . . . . . : 2a02:8011:xxxx:xxxx::1And from the fritz box:
2606:4700:4700::1111
192.168.178.1
1.1.1.1
DNS servers used 212.23.3.100
212.23.6.100 (currently used for standard queries)
2a02:8010:1::212:23:3:100
I am assuming 192.168.178.1 and the masked out ipv6 are your fritz box.