Difference between revisions of "MTU/MSS - How to test using PING"
From Tech-Wiki
(Created page with "Category:Wireshark MTU = max transmission unit of a Layer 2 Frame<br /> MSS = max segment size of a Layer 4 protocol<br /> <br /> For TCP/IP:<br /> MSS = MTU-40 (TCP and IP h...") |
|||
| Line 5: | Line 5: | ||
For TCP/IP:<br /> | For TCP/IP:<br /> | ||
MSS = MTU-40 (TCP and IP headers are 40 bytes)<br /> | MSS = MTU-40 (TCP and IP headers are 40 bytes)<br /> | ||
| − | ping -f -l X (set do not fragment and set icmp payload to X) | + | |
| − | + | Testing MTU using Winodws ping command<br /> | |
| + | ping -f -l X hostname (set do not fragment and set icmp payload to X) | ||
| + | |||
| + | Simple loop for Windows ping testing | ||
| + | FOR /L %A IN (1200,1,1473) DO ping -f -n 3 -l %A hostname >> C:\mtu-test.txt | ||
| + | |||
If X = 1388 gets a reponse then<br /> | If X = 1388 gets a reponse then<br /> | ||
| − | MTU = X + 28 (for | + | MTU = X + 28 (20 for IP header and 8 for the ICMP header)<br /> |
MTU = 1416<br /> | MTU = 1416<br /> | ||
| − | |||
MSS = 1416 - 40 = 1376 | MSS = 1416 - 40 = 1376 | ||
Revision as of 02:39, 14 June 2011
MTU = max transmission unit of a Layer 2 Frame
MSS = max segment size of a Layer 4 protocol
For TCP/IP:
MSS = MTU-40 (TCP and IP headers are 40 bytes)
Testing MTU using Winodws ping command
ping -f -l X hostname (set do not fragment and set icmp payload to X)
Simple loop for Windows ping testing
FOR /L %A IN (1200,1,1473) DO ping -f -n 3 -l %A hostname >> C:\mtu-test.txt
If X = 1388 gets a reponse then
MTU = X + 28 (20 for IP header and 8 for the ICMP header)
MTU = 1416
MSS = 1416 - 40 = 1376