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View Full Version : For Timestamps!!! i need to know some info!!!



erogic1
03-15-01, 11:37 PM
First of all, what does this mean -"Timestamps add 12 bytes to the TCP header of each packet, reducing the space available for useful data". i have timestamps on right now and now it says this, so what does it mean??

And second of all this is a good connection or what??
TCP options string = 020405ac010303030101080a000000000000000001010402

MTU = 1492
MTU seems to be optimized for PPPoE... If you are not on a PPPoE connection, consider increasing your MTU to 1500 for optimal throughput.

MSS = 1452
Maximum useful data in each packet = 1440, which is less than MSS because of Timestamps, or other TCP/IP options used.
MSS is optimized for PPPoE. If you are not on a PPPoE connection, consider increasing your MTU value.

Default Receive Window (RWIN) = 511104
RWIN Scaling (RFC1323) = 3 bits
Unscaled Receive Window = 63888
RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
255552 (MSS x 44 * scale factor of 4)
127776 (MSS x 44 * scale factor of 2)
63888 (MSS x 44)

bandwidth * delay product:
Your RcvWindow limits you to: 20444.16 kbps (2555.52 KBytes/s) @ 200ms
Your RcvWindow limits you to: 8177.664 kbps (1022.208 KBytes/s) @ 500ms

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

So is it good or what??
thz for any replies!

dannjr
03-16-01, 06:05 AM
setting Tcp13230pts to 3 enables Time stamps and scaling setting it to 1 turns on scaling only..
If you turn on timestamps and on some connections it can make a difference like on mine for some reason..
Anyway if you turn that on
MSS will be figured at -52 instead of -40 that small amount may never hurt your connection but it will use more off the MTU..

Another example
MTU 1496 with timestamps enabled.
MSS is 1444 insted of 1456

To me it really isn't enough to kill the speed but for others it may..
If it kills it allot there is something else going on that needs to be looked at

erogic1
03-16-01, 09:40 AM
how do u change the setting Tcp13230pts to 3?

[ 03-16-2001: Message edited by: death ]