SG Broadband Community

? is in the Subject.


TCP options string = 020405b0010303010101080a000000000000000001010402

MTU = 1496
MTU is fully optimized for broadband.

MSS = 1456
Maximum useful data in each packet = 1444, which is less than MSS because of Timestamps, or other TCP/IP options used.

Default Receive Window (RWIN) = 128128
RWIN Scaling (RFC1323) = 1 bits
Unscaled Receive Window = 64064
RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
512512 (MSS x 44 * scale factor of 8)
256256 (MSS x 44 * scale factor of 4)
64064 (MSS x 44)

bandwidth * delay product:
Your RcvWindow limits you to: 5125.12 kbps (640.64 KBytes/s) @ 200ms
Your RcvWindow limits you to: 2050.048 kbps (256.256 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 51 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

Set to 1 for scaling 3 for scaling and timestamps most ISP's aren't using timestamp
The entry to change is Tcp1323Opts....
Some connections run a little faster with it enabled....

Consider me a Newbie DJ


Where would I change the Tcp1323Opts in the Registry and also how would I know if my ISP supports Timestamps? Thanx

Forget it, I found it and it was already enabled at 1

[ 03-17-2001: Message edited by: Prey521 ]

One more question.


What is "Selctive Acks" and should it be enabled or disabled and to what number should Max Duplicate Acks be set?

Please go to this http://www.dslreports.com/front/drtcp.htmlRL
Download DR. TCP to your desktop
Where it saids adapter settings, select your adapter
Where it says Windows sclaing- yes
Where it says Selective Acks-yes
Path MTU Discovery - yes
Black Hole Detection - No
TTL-64 or 32 (up to you) No affect on speed.

Where it says Time Stamping, yes
click apply
Reboot for changes to take affect

Do not change any numbers in this box unless you know what you are doing.
A blank box only means that the default setting is being used