Revision History of Question #578 from FAQ tweaks
Differences (Rev #1 vs Current):
DRTCP works with Win95/98/98se/ME/2K/XP. | DRTCP works with Win95/98/98se/ME/2K/XP (not
> Vista).
This is not meant to be a Tylenol inspiring? | This is not meant to be a Tylenol-inspiring?
technical documentation? but merely a basic g technical documentation? but merely a basic g
uide to understanding how you can best use th uide to understanding how you can best use th
is great tool (surprise at end). is great tool (surprise at end).
DRTCP is <B>not</b> a patch? but a shortcut ( DRTCP is <B>not</b> a patch? but a shortcut (
GUI interface) into your registry. It does no GUI interface) into your registry. It does no
t enter <I>anything</i> by itself. You can do t enter <I>anything</i> by itself. You can do
wn-load DRTCP <a href=/front/drtcp.html><b>he | wnload DRTCP <a href=/front/drtcp.html><b>her
re</b></a></p><CENTER><IMG SRC=/front/drtcp.g | e.</b></a></p><CENTER><IMG SRC=/front/drtcp.g
if></center><P><B>TCP Receive Window</b>: Thi if></center><P><B>TCP Receive Window</b>: Thi
s is where you set RWIN (RcvWindow). RWIN is s is where you set RWIN (RcvWindow). RWIN is
the single most important tweak. Raising Rwin | the single most important tweak. Raising RWIN
from default (8760 for Win95/98/98SE/NT and from default (8760 for Win95/98/98SE/NT and
17520 for WinME/2K/XP)? can greatly improve d | 17520 for WinME/2K/XP) can greatly improve do
ownload speeds. Why? Here is my kindergarten | wnload speeds. Why? Here is my kindergarten a
analogy: Default RWIN for broadband? is like | nalogy: Default RWIN for broadband is like ha
having a tiny straw in a thick milk shake? on | ving a tiny straw in a thick milk shake? only
ly so much can get through the straw (line)? | so much so fast can get through the straw (l
so fast. By putting a larger straw (higher RW | ine). By putting a larger straw (higher RWIN)
IN) in that same thick shake? you allow more | in that same thick shake? you allow more sha
shake (data) to come through faster? to a poi | ke (data) to come through faster? to a point
nt that is. After which? there is no more imp | that is. After there is no more improvement?
rovement? and shake (data) can start spilling | shake (data) can start spilling all over (pac
all over (packet loss). So the key is? to fi | ket loss). So the key is to find an RWIN that
nd an RWIN that fits your line just right. Th | fits your line just right. This is <I>blank<
is is <I>blank</i> before changing from defau | /i> before changing from default.</p><P>The f
lt.</p><P>The formula for finding your "ideal | ormula for finding your "ideal" RWIN is to ta
" RWIN? is to take your latency (average ping | ke your latency (average ping time in ms x 1.
time in ms x 1.5)? multiply that by your adv | 5)? multiply that by your advertised (downloa
ertised (download) speed? and divide that by | d) speed and divide that by 8.
8. <
<B>Note</b>: If setting RWIN below 8192? try <B>Note</b>: If setting RWIN below 8192? try
using <I>even</i> multiples of MSS. using <I>even</i> multiples of MSS.
<B>Windows Scaling</b>: 65535 is the highest <B>Windows Scaling</b>: 65535 is the highest
RWIN you can use without Windows Scaling bein RWIN you can use without Windows Scaling bein
g turned on. So simply put? Scaling is needed | g turned on. Simply put? Scaling is needed to
to enter any number higher than 65535. Howev | enter any number higher than 65535. However?
er? you must also have the updated vtcp.386 p | you must also have the updated vtcp.386 patc
atch (WinME/2K/XP does not need a patch). Rel | h (WinME/2K/XP does not need a patch). Relax?
ax though? most users do not need to go highe | though; most users do not need to go higher
r than 65535. Windows Scaling <B>"Defaults"</ | than 65535. Windows Scaling <B>"Defaults"</b>
b> to off (same as No). | to off (same as No).
|
<B>Time Stamping</b>: The need for this seems | <B>Time Stamping</b>: The need for Time Stamp
to be in question? at least with RWIN under | ing seems to be in question? at least with RW
65535. If you have a line where latency varie | IN under 65535. If you have a line where late
s a lot? or a "long fat pipe" (for example? p | ncy varies a lot? or a "long fat pipe" (for e
ure satellite connection)? then Time stamping | xample? pure satellite connection)? then Time
should be beneficial? so experiment with it. | Stamping should be beneficial? so experiment
Time Stamping <B>"Defaults"</b> to off (same | with it. Time Stamping <B>"Defaults"</b> to
as No). | off (same as No).
|
| <B>Selective Acks</b>: Selective Acks improve
<B>Selective Acks</b>: This improves throughp | throughput (speed) on lines that tend to los
ut (speed) on lines that tend to lose packets | e packets by retransmitting <I>only</i> packe
? by re-transmitting <I>only</i> packets that | ts that were lost? if any. <B>"Defaults"</b>
were lost? if any. <B>"Defaults"</b> to on ( | to on (same as Yes) in Win98/98SE/ME/2K/XP an
same as Yes) in Win98/98SE/ME/2K/XP and is N/ | d is N/A in Win95/NT.
A in Win95/NT. |
| <B>Path MTU Discovery</b>: This feature autom
<B>Path MTU Discovery</b>: This automatically | atically sets your MTU (maximum transmission
sets your MTU (maximum transmission unit) to | unit) to what type of line you have (dial-up
what type of line you have (dial-up (576)? b | (576)? broadband 1492-1500). This is the size
roadband 1492-1500). This is the size of pack | of packets you can receive. The highest MTU
ets that you can receive. The highest MTU tha | that one can have is 1500. For users with PPP
t one can have is 1500. For users with PPPoE | oE connection software? it's 1492 and lower.
connection software? 1492 and lower. Without | Without PPPoE? it should default to 1500. <B>
PPPoE? it should default to 1500. <B>"Default | "Defaults"</b> to on (same as Yes) in Win98/9
s"</b> to on (same as Yes) in Win98/98SE/ME/2 | 8SE/ME/2K/XP/NT and is N/A in Win95.
K/XP/NT? and is N/A in Win95. |
| <B>Black Hole Detection</b>: Black Hole Detec
<B>Black Hole Detection</b>: This discovers r | tion discovers routers on the WEB that cause
outers on the WEB that cause MTU Discovery to | MTU Discovery to work sub-optimally. <B>"Defa
work sub-optimally. <B>"Defaults"</b> to off | ults"</b> to off (same as No) in Win95/98/98S
(same as No) in Win95/98/98SE/ME/2K/XP. | E/ME/2K/XP.
|
<B>Max. Duplicate ACKs</b>: This allows for f | <B>Max. Duplicate ACKs</b>: This function all
aster re-transmission of packets (information | ows for faster retransmission of packets (inf
)? when packet loss is encountered. <B>"Defau | ormation) when packet loss is encountered. <B
lts"</b> to blank? where blank stands for 3 i | >"Defaults"</b> to blank? where blank stands
n Win98/98SE/ME? 2 in WinNT/2K/XP? and is N/A | for 3 in Win98/98SE/ME? 2 in WinNT/2K/XP and
in Win95. | is N/A in Win95.
|
<B>TTL</b>: Time To Live is the amount of hop | <B>TTL</b>: Time To Live (TTL) is the amount
s (servers) that a transmission of packets wi | of hops (servers) that a transmission of pack
ll take before all packets are lost. If you w | ets will take before all packets are lost. If
ere receiving packets from 20 hops away? and | you were receiving packets from 20 hops away
TTL was set to 19 or less? all packets would | ? and TTL was set to 19 or less? all packets
be lost before they reach you. Not a speed tw | would be lost before they reach you. Not a sp
eak. <B>"Defaults"</b> to blank? where blank | eed tweak. <B>"Defaults"</b> to blank? where
stands for 32 in Win95? 128 in Win98/98SE/ME/ | blank stands for 32 in Win95 and 128 in Win98
2K/XP. | /98SE/ME/2K/XP.
<B>Adapter settings</b>: This is where you se <B>Adapter settings</b>: This is where you se
t your MTU. Use the drop-down menu to find yo t your MTU. Use the drop-down menu to find yo
ur NIC (Ethernet card). <I>If you do not know ur NIC (Ethernet card). <I>If you do not know
which adapter you should set? please ask</i> which adapter you should set? please ask</i>
. Do not set them all the same. (Note: If you . Do not set them all the same. (Note: If you
r MTU is 1500 by <I>default</i>? it will be b r MTU is 1500 by <I>default</i>? it will be b
lank in DRTCP. Also: Only physical NIC's supp | lank in DRTCP.) Also? only physical NICs supp
orted for XP? no dial-up adapters. orted for XP? no dial-up adapters.
<B>Note:</b> DRTCP <I>defaults</i> to showing <B>Note:</b> DRTCP <I>defaults</i> to showing
the dial-up adapter. This has <I>nothing</i> the dial-up adapter. This has <I>nothing</i>
to do with the other settings. It does <I>no to do with the other settings. It does <I>no
t matter</i> which adapter is visible when se t matter</i> which adapter is visible when se
tting anything except MTU. Also: Upon reboot | tting anything except MTU. Also? upon reboot?
the dialup adapter will be showing? <I>regard | the dial-up adapter will be showing <I>regar
less</i> of which adapters MTU was set. | dless</i> of which adapter's MTU was set.
<B>ICS Settings</b>: Internet MTU is set when <B>ICS Settings</b>: Internet MTU is set when
Internet Connection Sharing (a Microsoft pro Internet Connection Sharing (a Microsoft pro
gram) is enabled and being used on your PC. T gram) is enabled and being used on your PC. T
his is where 2 or more PCs share the same Int his is where 2 or more PCs share the same Int
ernet connection? though only one can b? surf ernet connection? though only one can b? surf
b? at a time. ICS MTU should match that of t b? at a time. ICS MTU should match that of t
he PC. This is grayed out if ICS is not being he PC. This is grayed out if ICS is not being
used (not ready for Win2K/XP). used (not ready for Win2K/XP).
<B>Also</b>: By right clicking on the logo an <B>Also</b>: By right clicking on the logo an
d choosing "About"? you will find information | d choosing "About?" you will find information
about the version of Windows you use. about the version of Windows you use.
Great? so what should you set all of these to Great? so what should you set all of these to
? Most users can leave all of them at <B>Defa ? Most users can leave all of them at <B>Defa
ult</b> (surprise!) except for RWIN? as this ult</b> (surprise!) except for RWIN? as this
has been determined to be best? most of the t | has been determined to be best most of the ti
ime? thus being <I>"Default"</i>. After makin | me? thus being <I>"Default."</i> After making
g any changes? click Save? then Exit? then <B | any changes? click Save? then Exit and then
>reboot</b> (restart) your PC. Use the <B>Tab | <B>reboot</b> (restart) your PC. Use the <B>T
</b> button on your keyboard to move about DR | ab</b> button on your keyboard to move about
TCP. <B>If you do not reboot? the settings wi | DRTCP. <B>If you do not reboot? the settings
ll not "take"</b>. | will not "take."</b>
DRTCP recommended by <A HREF=http://www.cisco DRTCP recommended by <A HREF=http://www.cisco
.com/warp/public/794/router_mtu.html#changing | .com/en/US/tech/tk175/tk15/technologies_tech_
><B>Cisco</b></a> | note09186a0080093bc7.shtml><B>Cisco</b></a>.
~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~
<I>Uninstall</i>: Since DRTCP is a GUI interf <I>Uninstall</i>: Since DRTCP is a GUI interf
ace (never mind)? it is not installed. Theref ace (never mind)? it is not installed. Theref
ore there is no <I>uninstall</i>. Right click | ore? there is no <I>uninstall</i>. Right clic
on DRTCP and choose Delete? if you wish to. | k on DRTCP and choose Delete? if you wish to.
<
To simply set your registry back to it's defa <
ult settings? set everything to "Default" or <
blank (cleared of value)? click Save? and reb <
oot. Done. <
<
> To simply set your registry back to its defau
> lt settings? set everything to "Default" or b
> lank (cleared of value)? click Save and reboo
> t. Done.
End.
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