NDT-DEV email list created

Revision: 476
Author:   

Date:     Tue Aug  9 05:57:20 2011
Log:      Feedback based fixes.
http://code.google.com/p/ndt/source/detail?r=476

Modified:
 /wiki/NDTProtocol.wiki

=======================================
--- /wiki/NDTProtocol.wiki      Tue Aug  9 03:04:02 2011
+++ /wiki/NDTProtocol.wiki      Tue Aug  9 05:57:20 2011
@@ -176,7 +176,7 @@
 The NDTP-Tests currently defines the following types of tests:

 || *Symbolic name* || *Integer value* || *Description* ||
-|| TEST_MID || 1 (1L << 0) || Middlebox test - a short (5 seconds)  
throughput s2c test with a limited CWND to check for a duplex mismatch  
condition. Moreover, it also checks the MSS value and does NAT detection ||
+|| TEST_MID || 1 (1L << 0) || Middlebox test - a short (5 seconds)  
throughput test from the Server to the Client with a limited CWND to check  
for a duplex mismatch condition. Moreover, it also checks the MSS value and  
does NAT detection ||
 || TEST_C2S || 2 (1L << 1) || 10 seconds C2S throughput test ||
 || TEST_S2C || 4 (1L << 2) || 10 seconds S2C throughput test ||
 || TEST_SFW || 8 (1L << 3) || Simple firewall test ||
@@ -187,11 +187,11 @@
 || *Symbolic name* || *Integer value* || *Description* ||
 || TEST_STATUS || 16 (1L << 4) || A special flag to notify the Server that  
this Client will respond to status requests ||

-All new Clients MUST support TEST_STATUS mechanism.
+All Clients MUST support TEST_STATUS mechanism.

 === Middlebox test ===

-The Middlebox test is a short throughput s2c test with a limited CWND to  
check for a duplex mismatch condition. Moreover, this test uses a  
pre-defined MSS value to check if any intermediate node will modify its  
connection settings.
+The Middlebox test is a short throughput test from the Server to the  
Client with a limited CWND to check for a duplex mismatch condition.  
Moreover, this test uses a pre-defined MSS value to check if any  
intermediate node will modify its connection settings.

 ==== MID protocol ====

@@ -207,18 +207,32 @@

 When the Client successfully connects, the NDT Server MUST start 5 seconds  
throughput test on the newly created connection.

-The NDT Server in the MID Throughput test MUST send packets through the  
newly opened connection as fast as possible (i.e. without any delays) for 5  
seconds. These packets must have the following size:
+The NDT Server in the MID Throughput test MUST send packets through the  
newly opened connection as fast as possible (i.e. without any delays) for 5  
seconds. These packets must be written using the buffer of the following  
size:
+{{{
+(The current maximum segment size (MSS))
+}}}
+
+If for some reasons it is not possible to use such a big buffer, the  
Server MUST use a 8192 Byte one. The content of the buffer SHOULD be as  
random as possible (to avoid any automatic compression mechanisms) and MUST  
include only printable characters. The maximum value of the congestion  
window during the MID Throughput test MUST be set to the following value:
 {{{
 2 * (The current maximum segment size (MSS))
 }}}

-If for some reasons it is not possible to send such packets, the Server  
MUST send a 8192 Byte packets. The content of these packets SHOULD be as  
random as possible and MUST include only printable characters.
-
-When the test is over, the Server MUST send its results encoded as strings  
in a TEST_MSG message to the Client:
+When the test is over, the Server MUST send its results encoded as strings  
in a TEST_MSG message to the Client. These results MUST contain the  
following variables:
+
+|| CurMSS || The current maximum segment size (MSS), in octets.||
+|| !WinScaleSent || The value of the transmitted window scale option if  
one was sent; otherwise, a value of -1. ||
+|| !WinScaleRcvd || The value of the received window scale option if one  
was received; otherwise, a value of -1. ||
+
+The above variables can be obtained by using a [http://www.web100.org/  
web100] project. All available web100 data variables are described in  
[NDTProtocol#Appendix_A._web100_variables Appendix A].
+
+The whole TEST_MSG message sent to the Client looks as following:

  
http://www.soldevelo.com/images/ndt/12.%20TEST_MSG%20message%20to%20Client.png

-Next, the Client MUST send to the Server its calculated throughput value  
encoded as string (float format) in a TEST_MSG message.
+Next, the Client MUST send to the Server its calculated throughput value  
encoded as string (float format) in a TEST_MSG message. The throughput  
value MUST be calculated using the following formula:
+{{{
+THROUGHPUT_VALUE = 8 * TRANSMITTED_BYTES / 1000 / TEST_TIME
+}}}

 At the end the Server MUST close the MID test session by sending an empty  
TEST_FINALIZE message.

@@ -287,9 +301,14 @@

 The Client MUST start 10 seconds throughput test and the Server MUST read  
transmitted data.

-The NDT Client in the C2S Throughput test MUST send a 8192 Byte packets  
through the newly opened connection as fast as possible (i.e. without any  
delays) for 10 seconds. The content of these packets SHOULD be as random as  
possible and MUST include only printable characters.
-
-When the Client stops streaming the test data (or the test routine at the  
Server times out), the Server MUST send to the Client its calculated  
throughput value encoded as string (float format) in the TEST_MSG message:
+The NDT Client in the C2S Throughput test MUST use a 8192 Byte buffer to  
send the packets through the newly opened connection as fast as possible  
(i.e. without any delays) for 10 seconds. The content of the buffer SHOULD  
be as random as possible (to avoid any automatic compression mechanisms)  
and MUST include only printable characters.
+
+When the Client stops streaming the test data (or the test routine at the  
Server times out after 11 seconds from the last TEST_START message), the  
Server MUST send to the Client its calculated throughput value encoded as  
string (float format) in the TEST_MSG message. The throughput value MUST be  
calculated using the following formula:
+{{{
+THROUGHPUT_VALUE = 8 * TRANSMITTED_BYTES / 1000 / TEST_TIME
+}}}
+
+The Server's TEST_MSG message looks as following:

  
http://www.soldevelo.com/images/ndt/20.%20Client%20its%20calculated%20throughput%20value%20encoded%20as%20string%20%28float%20format%29%20in%20the%20TEST_MSG%20message.png

@@ -309,7 +328,7 @@

 All messages exchanged between the Client and the Server during the S2C  
protocol are sent using the same connection and message format as the  
NDTP-Control protocol. Only the throughput packets are sent on the new  
connection and do not follow the NDTP-Control protocol message format.

-As a first step the Server MUST bind the new port and send a TEST_PREPARE  
message containing this port number to the Client:
+As a first step the Server MUST bind the new port. Next, it MUST send a  
TEST_PREPARE message containing this port number to the Client using the  
NDTP-Control connection:

  
http://www.soldevelo.com/images/ndt/22.%20TEST_PREPARE%20message%20containing%20this%20port%20number%20to%20the%20Client.png

@@ -321,26 +340,56 @@

 The Server MUST start 10 seconds throughput test and the Client MUST read  
the transmitted data.

-The NDT Server in the S2C Throughput test MUST send a 8192 Byte packets  
through the newly opened connection as fast as possible (i.e. without any  
delays) for 10 seconds. The content of these packets SHOULD be as random as  
possible and MUST include only printable characters.
-
-When the Server stops streaming the test data, it MUST send to the Client  
its calculated throughput value (encoded as string in float format), amount  
of unsent data in the socket send queue (encoded as string in integer  
format) and overall number of sent bytes (encoded as string in float  
format) in the TEST_MSG message:
+The NDT Server in the S2C Throughput test MUST use a 8192 Byte buffer to  
send the packets through the newly opened connection as fast as possible  
(i.e. without any delays) for 10 seconds. The content of the buffer SHOULD  
be as random as possible (to avoid any automatic compression mechanisms)  
and MUST include only printable characters.
+
+When the Server stops streaming the test data, it MUST send to the Client  
its calculated throughput value (encoded as string in float format), amount  
of unsent data in the socket send queue (encoded as string in integer  
format) and overall number of sent bytes (encoded as string in float  
format) in the TEST_MSG message. The throughput value MUST be calculated  
using the following formula:
+{{{
+THROUGHPUT_VALUE = 8 * SENT_BYTES / 1000 / TEST_TIME
+}}}
+
+The Server's TEST_MSG message looks as following:

  
http://www.soldevelo.com/images/ndt/23.%20overall%20number%20of%20sent%20bytes%20%28encoded%20as%20string%20in%20float%20format%29%20in%20the%20TEST_MSG%20message.png

 All these values MUST be separated by spaces.

-Next, the Client MUST send to the Server its calculated throughput value  
encoded as string (float format) in the TEST_MSG message:
+Next, the Client MUST send to the Server its calculated throughput value  
encoded as string (float format) in the TEST_MSG message. The throughput  
value MUST be calculated using the following formula:
+{{{
+THROUGHPUT_VALUE = 8 * TRANSMITTED_BYTES / 1000 / TEST_TIME
+}}}
+
+The Client's TEST_MSG message looks as following:

  
http://www.soldevelo.com/images/ndt/24.%20MUST%20send%20to%20the%20Server%20its%20calculated%20throughput%20value%20encoded%20as%20string%20%28float%20format%29%20in%20the%20TEST_MSG%20message.png

-In the same time the Server SHOULD send its web100 data variables gathered  
during S2C throughput test to the Client. Each variable name/value pair  
should be encoded as strings in a separate TEST_MSG message using the  
following format:
+In the same time the Server SHOULD send its  
[NDTProtocol#Appendix_A._web100_variables web100 data variables] gathered  
during S2C throughput test to the Client. Each variable name/value pair  
should be encoded as strings in a separate TEST_MSG message using the  
following format:
 {{{
 web100_var_NAME: web100_var_VALUE\n
 }}}

 where '\n' is a single new line character.

-All available web100 data variables are described in  
[NDTProtocol#Appendix_A._web100_variables Appendix A].
+All available web100 data variables are described in  
[NDTProtocol#Appendix_A._web100_variables Appendix A]. The Server MUST send  
at least the following variables:
+ # AckPktsIn
+ # CountRTT
+ # CongestionSignals
+ # CurRTO
+ # CurMSS
+ # DataBytesOut
+ # DupAcksIn
+ # MaxCwnd
+ # MaxRwinRcvd
+ # PktsOut
+ # PktsRetrans
+ # RcvWinScale
+ # Sndbuf
+ # SndLimTimeCwnd
+ # SndLimTimeRwin
+ # SndLimTimeSender
+ # SndWinScale
+ # SumRTT
+ # Timeouts
+

 At the end the Server MUST close the S2C test session by sending an empty  
TEST_FINALIZE message.