DBAs and responsibility in data security

hello folks, this question is more into politics rather than technical. If you had a business and you're hiring a DBA, how would you restrict a DBA from not viewing certain data? The things which can come into my mind are:
- Enforce the DBA to use a non-dba account with just access to SYSTEM tables and dictionary views
- Don't give the DBA root/oracle access in case of Unix or 'Administrator' access in case of Windows
Feedback is welcome

Doesn't Database Vault just in effect demote the DBA to super-operatorNo. In a nutshell, DBV separates access into three separate responsibilities - the actual user, the account creator and the access policy administrator. A DBA can still have SYSDBA privileges but, under DBV:
(1) The DBA cannot create their own accounts, the account creator does that
(2) The access policy administrator can put rules in place such as "no SYSDBA access during working hours" or "nobody can look at the data in this table just because they have SELECT ANY TABLE privilege".
You now have to worry about the security admin reading all your data.The idea is you have three separate roles filled by three different people. The user creator won't be able to put in place the policies which would allow them to access the data. The policy administrator won't be able to create users. Of course this is wholly procedural but there's no point in splashing out for DB Vault without putting the security practices in place too.
How can a DBA backup the database if they can't read some of the data?Precisely what part of any DBAs job requires them to have unfettered access to your mediacl records or your credit card numbers? The backup will be done by an account that has the necessary priveleges but the DBA won't be able to connect as that account.
what prevents them from accessing the datafiles directly / on a seperate system
without database vault? Access will be controlled and audited. Somehow. Read the docs.
Look, I have seen a demo of this stuff last year. It's very clever. Probably not uncrackable but I think would require extremely determined malefactors working in concert to subvert a properly implemented DBV set-up. It would certainly save a DBA who has had a bad month on the horses from succumbing to temptation.
Besides, to a large extent this is about demonstrating compliance to external auditors.
Cheers, APC

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HT1414 My wife gave me her older ipad. I have reset and removed all data. My Apple ID (Ipod touch) is not an email adress, but when I try to stu up the ipad it asks for my Apple ID, then tells me that for security reasons the Apple ID must be in email for

My wife gave me her older ipad. I have reset and removed all data. My Apple ID (Ipod touch) is not an email adress, but when I try to stu up the ipad it asks for my Apple ID, then tells me that for security reasons the Apple ID must be in email format?

Change it to an email address.
-> https://appleid.apple.com/

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The following article(s) may help you.
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How to restrict the Request and Response process in that cookies should be Secure way SAP Portal 7.0 ?

Dear Experts,
Please any one can help me i am getting one security issue.Some third party tools using and hacking the Request and Response of the Server.That time there taking one successfully Request (GET http://1.1 302 found) and Response (http://1.1 200 ok).In this request based on again there giving some invalidate credential in that time server giving request replacing for success fully Request that time there login in to portal successfully(Bypassing).In this Request level only getting the information for URL and set-cookies only.Here any process is there to restrict the set cookies.like JSESSIONMARKID and JSESSIONID SAP_LB.
We are using 7.0 Version and SP 12. Please share you are solutions because of this is very high problem here.
Thanks for Advance
Thanks and regrades,
Durga Rao.

Dear Samuli,
Thanks for the Replay,
We are using HTTPS and SSL confined but man in the middle types of attack is happening here there using one tool based one there taking the Request and Response.The below given cookie are available in that request.
According to this , set-cookie: JSESSIONMARKID , JSESSIONID and MYSAPSSO2 values are user login time it will change every time are not.
After capturing above response HTTP/1.1 302 etc , when user gives valid credentials and logs in ,
and now ill give wrong password and wrong user id and on click of log on button, i can intercept the request and response coming from the server and when i replace this valid response stil i am able to loggin in to the portal , which should not happen as JESSIONMARKID is changed , server should not allow , but it is loggin in.Standard Login page also allowing to login in this case.
My server version is EP 7.0 SP 12.
Please suggest a solution so that if we restric the hacker at this stage , no matter he can never hijack the sesiona and login with invalid username and password.
Thanks for Advance
Thanks and regrades,
Durga Rao.

Database Data Security: both from within (using MIMEbase64 encoding) and from without (using encryption).

In my MDB file databases (Jet 4.x format) I turn on both compression and encryption. This gives me data security from without, meaning, I can't open a MDB file in a Word Processing software (or otherwise) and read the data in a humanly recognized
format.   But I am also using MIMEbase64 encoding of my stored data so that the data is humanly unreadable from within - meaning that anyone performing an SQL query will not be able to humanly read the data in my database. I do the decoding
(from MIMEbase64) within my end-user software interfaces to the databases.
I found out just recently (last few months) that I can do this from Win32 Perl, so I encorporated this feature into my Perl database applications.   Only thing is that MIMEbase64 increases the size of the data stored.
Is there a better encoding strategy available today which might actually compress the data a little?

INSTRUCTIONS FOR SECURE/CUSTOM (non-formula based) TEXTFILE ENCODING (should be undecipherable w/o mappings file):
by Eric C. Hansen. You may freely use these encoding instructions, and the code I have provided, but please
acknowledge me as the author where credit is due - such as in a publication. And do not try to sell it.
However, any code I have provided you may freely use in any programs you write to be sold for your own profit,
except you may not attempt to sell this encoding scheme (or my code provided), as a generic encoding tool, for
general use, to be marketed as a turn-key custom encoding solution.
(1) Create a unique code list
Using the characters: A-Z a-z 0-9 only. That's 62 characters only.
62 (1 char codes) + 3844 (2 char codes) + 238,328 (3 char codes) = 242,234 total codes
62x1 + 62x62 + 62x62x62
REMINDS ME of my college Genetics course i.e. dominant/recessive trait inheritance tables
EXAMPLE CODES: a, k, 3c, A4, xy1, H8j
(2) Create a unique word(+punc) list from your textfile which is to be encoded. You know how to do this.
Example of 9 words(+punc) found between whitespace within a textfile input line:
"Hello", this is Mr. Bell-va-deer. My number is 999-342-8998.
1 2 3 4 5 6 7 8 9
PERL code for STEPS 3-7 is provided below. Code for STEP 1 above was previously provided.
You should have little trouble writing the textfile encode/decode logic yourself.
(3) Read your list of unique codes into an array.
(4) Read your list of unique words(+punc) into another array.
LOOP #-- 0 to number of elements in words array
(5) select a random code and a random word(+punc) from the 2 arrays.
(6) now remove that code and that word(+punc) from each array using "splice".
(7) then save them as key/val pairs to persistent Perl SDBM database files ("mappings").
END LOOP
(8) Once you have your persistent, random code/word mappings, you can convert your textfile
to an encoded textfile. Read in one line at a time from your textfile (chomp), parse the words(+punc.)
between whitespace within that line, then for each word(+punc) parsed, perform
the word-to-code mapping conversions by doing a lookup within the Perl SDBM database
file of key/val pairs, where KEY=word and VAL=code. You will then need to
concatenate these codes (space delimited) to your outputline, in the same order as found in your
inputline, finally writing the outputline (newline "\n" terminated) to your new encoded textfile.
(9) Keep your persistent Perl SDBM database file ("mappings") in SAFE KEEPING, with a naming
convention of your choice that perhaps hides any relationship to the name of
your encoded text document - which it specifically pertains to. But keep a record of that joint
relationship somewhere. Keep a copy of both the original textfile and the encoded textfile,
or perhaps you'd like to keep just the encoded textfile?, and not the original? You can always decode it.
(10) Send your encoded text document via email as an attachment, to the recipient of your choice.
(11) Upload your persistent Perl SDBM database "mappings" file to your secure login FTP download site.
NOTE: If your encoded text document is very large, you may want to reverse 10 & 11, putting the encoded file
on the FTP site, and sending the Perl SDBM database file ("mappings") as the email attachment.
(12) Call your recipient to see if they have received the encoded textfile, email attachment.
Let them know that the "mappings" file is uploaded for them to download from the FTP site.
You can have a LINGO you both use/know on the phone, to secretly convey this message, if you like,
to avoid possible interception of this sensitive information.
Recipient will then take the encoded textfile email attachment, the FTP downloaded "mappings" file,
and place them both in a directory on their PC where the Perl decoding program is located which you
had previously sent them to handle all the decoding anytime you send them an encoded textfile + "mappings".
Recipient will run the Perl decoding utility program to create the original textfile.
use Win32; #-- as you can see, I use a Windows O/S Perl distribution.
use IO::Handle;
use SDBM_File; #-- my understanding is this module comes standard with every Perl distribution
use Fcntl;
$PWD=Win32::GetCwd(); #-- get current working directory on Windows O/S platform.
srand; #-- random seeding initiated, do this just once at top.
@codesARR=(); @wordsARR=(); #-- initialize the arrays
print "working. please wait...\n\n";
unlink( "$PWD\\Project_0836_Mappings_CtoW.pag" )
if (-e "$PWD\\Project_0836_Mappings_CtoW.pag" );
unlink( "$PWD\\Project_0836_Mappings_CtoW.dir" )
if (-e "$PWD\\Project_0836_Mappings_CtoW.dir" );
unlink( "$PWD\\Project_0836_Mappings_WtoC.pag" )
if (-e "$PWD\\Project_0836_Mappings_WtoC.pag" );
unlink( "$PWD\\Project_0836_Mappings_WtoC.dir" )
if (-e "$PWD\\Project_0836_Mappings_WtoC.dir" );
unlink( "$PWD\\Project_0836_Mappings.txt" )
if (-e "$PWD\\Project_0836_Mappings.txt" );
$cnt1=0; $ret="Y";
open(CODES,"$PWD\\codes.txt") || do {$ret="N";};
if ($ret eq "N") {
print "Codes input file not opened \n";
sleep 5; die;
while (<CODES>) {
chomp $_;
$codesARR[$cnt1]=$_;
$cnt1++;
print $cnt1 . " codes loaded\n\n";
close(CODES);
$cnt2=0; $ret="Y";
open(WORDS,"$PWD\\words.txt") || do {$ret="N";};
if ($ret eq "N") {
print "Words input file not opened \n";
sleep 5; die;
while (<WORDS>) {
chomp $_;
$wordsARR[$cnt2]=$_;
$cnt2++;
print $cnt2 . " words loaded\n\n";
close(WORDS);
sleep 3; #-- a little time to check on record counts loaded to both arrays
tie( %Project_0836_Mappings_WtoC, "SDBM_File", '.\Project_0836_Mappings_WtoC', O_RDWR|O_CREAT, 0666 );
if (tied %Project_0836_Mappings_WtoC) {
print "WtoC Hash/SDBM File are now tied\n\n";
} else {
print "Could not tie WtoC Hash/SDBM File\n\n"; sleep 5; die;
tie( %Project_0836_Mappings_CtoW, "SDBM_File", '.\Project_0836_Mappings_CtoW', O_RDWR|O_CREAT, 0666 );
if (tied %Project_0836_Mappings_CtoW) {
print "CtoW Hash/SDBM File are now tied\n\n";
} else {
untie(%Project_0836_Mappings_WtoC); #-- close the successful tie made directly above
print "Could not tie CtoW Hash/SDBM File\n\n"; sleep 5; die;
open (OUT,"> $PWD\\Project_0836_Mappings.txt");
OUT->autoflush(1);
$cnt2=$#wordsARR; #-- we do this because we will be removing elements from wordsARR
for ($i=0; $i<=$cnt2; $i++) {
$index = rand @codesARR; # get a random index from the codes array
$code = $codesARR[$index]; # get the value of that array element
splice(@codesARR,$index,1); # removes only this element from the codes array.
$index = rand @wordsARR; # get a random index from the words array
$word = $wordsARR[$index]; # get the value of that array element
splice(@wordsARR,$index,1); # removes only this element from the words array.
$Project_0836_Mappings_WtoC{$word}=$code; # key/value pair where: word is key, code is value
$Project_0836_Mappings_CtoW{$code}=$word; # key/value pair where: code is key, word is value
print "Your Mappings have been created and saved to (.dir and .pag extension files)\n\n";
print OUT "Here are your Mappings you just created:\n\n";
foreach $key (keys %Project_0836_Mappings_WtoC) {
print OUT "word=" . $key . " code=" . $Project_0836_Mappings_WtoC{$key} . "\n";
print OUT "##################################################\n";
foreach $key (keys %Project_0836_Mappings_CtoW) {
print OUT "code=" . $key . " word=" . $Project_0836_Mappings_CtoW{$key} . "\n";
untie(%Project_0836_Mappings_WtoC); #-- now you have saved a persistent word/code mappings file
untie(%Project_0836_Mappings_CtoW); #-- now you have saved a persistent code/word mappings file
close(OUT);
print "Done. Goodbye!\n";
sleep 5;
exit;

Problem to calculate the coherence (using NetworkFunction-VI) with only 1 row of data for each, the stimulus and response input

Hello,
I am trying to calculate the coherence of a stimulus and response
signal using the Network Functions (avg) VI's. The problem is that I
always get a coherence of "1" at all frequencies. This problem is
already known (see KnowledgeBase document: Why is the Network Functions (avg) VI's Coherence Function Output "1"?).
My trouble is that the described solution (-> the stimulus and response input matrices need to have at least two rows to get non-unity coherence values) doesn't help me much, because I only have one array of stimulus data and one array of response values.
Thus, how can I fullfil the 'coherence-criteria' to input at least two rows of data each when I just have one row of data each?
Any hint or idea is very much appreciated. Thanks!
Horst

With this weird board layout, I'm not sure whether you were asking me, but, on the assumption that you were, here goes:
I found no need to use the cross-power spectrum and power spectrum blocks
1... I was looking for speed.
2... I already had the component spectral data there, for other purposes. From that, it's nothing but addition and multiplication.
3... The "easy" VIs, assume a time wave input, as I recall. Which means they would take the same spectrum of the same timewave several times, where I only do it once.
I have attached PNGs of my code.
The PROCESS CHANNEL vi accepts the time wave and:
1... Removes DC value.
2... Integrates (optional, used for certain sensors).
3... Windows (Hanning, etc. - optional)
4... Finds spectrum.
5... Removes spectral mirrors.
6... Scales into Eng. units.
7... From there, you COULD use COMPLEX-TO-POLAR, but I don't care about the phase data, and I need the MAG^2 data anyway, so I rolled my own COMPLEX-TO-MAG code.
The above is done on each channel. The PROCESS DATA vi calls the above with data for each channel. The 1st channel in the list is required to be the reference (stimulus) channel.
After looping over each channel, we have the Sxx, Syy, and Sxy terms. This code contains some averaging and peak-picking stuff that's not relevant.
From there, it's straightforward to ger XFER = Sxy/Sxx and COHERENCE = |Sxy|^2 / (Sxx * Syy)
Note that it uses the MAGNITUDE SQUARED of Sxy. Again, if you use the "easy" stuff, it will do a square-root operation that you just have to reverse - it is obtained faster by the sum of the squares of the real and imag parts.
Hope this helps.
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks
Attachments:
ProcessChannel.png ‏25 KB

On mozilla's OWN WEBSITE I get the message 'Your Firefox is out of date and may contain a security risk!" but I just download and installed the latest version?

I have the latest version of firefox to date (10/15/2014 v32) and I still get messages while on various websites (Youtube, Google, Gmail) telling me that Your Firefox is out of date and may contain a security risk.
I even get that message on the support pages of mozilla.org??
I've tried the about:config reset the useragent(s) fix but that doesn't work.
I've tried browsing in safe mode and still get the error.
Why is this False/Positive happening?
Thanks

hello your useragent (the information the browser sends to websites to identify its version) - apparently mistakenly - shows this:
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0.1) Gecko/20140923 '''Firefox/4.0.0; xs-A30GTmfXR3o;CkHZPf;'''
probably some sort of unwanted software has overwritten it. please refer to this article in order to reset the user-agent settings in firefox:
[[Websites say that Firefox is outdated or incompatible even though it's the latest version]]
in case this does not help, please try to reset the whole browser:
[[Reset Firefox – easily fix most problems]]

Security based on the position and responsibility of Siebel tables.

Hi Forum,
We have a requirement to show some reports based on OLTP (Siebel Base tables with S_) tables. so we have created a repository and created few reports in OBIEE.
Now we want to implement security based on these tables. Like siebel users will be accessing these reports, So how do we implement security based on the position and responsibility of Siebel tables.
I request to share any links or docs pertaining to above mentioned implementation.
Thanks

Could be interference
AirPort and Bluetooth: Potential sources of wireless interference
Try:
- Reseting the BT headset
- Reset the iOS device. Nothing will be lost
Reset iOS device: Hold down the On/Off button and the Home button at the same time for at
least ten seconds, until the Apple logo appears.
- Reset network settings: Settings>General>Reset>Reset Network Settings. You will have to rejoin all wifi networs and re-pair all BT devices

Hi i forget my security questions and my birth date so what can i do ?

hi i forget my security questions and my birth date so what can i do ?
so please help me :(

You forgot your own birthdate?

OBIEE-EBS data security integration

Hi all,
I am trying to implement the HR-Org based data security in EBS-OBIEE integration.
After creating the initialization blocks EBS Single Sign-on Integration,Get Oracle EBS Security Context,Group-EBS Responsibility I have created a new initialization block HR Organizations to populate the session variable "HR_ORG" and I am using the following the query.
Even though the session variables GROUP and USER are getting their values correctly and integration works fine, the variable HR_ORG says "has no value definition".
[nQSError: 10058] A general error has occurred. [nQSError: 23006] The session variable, NQ_SESSION.HR_ORG, has no value definition. (HY000)
SQL Issued: SELECT "Per Business Groups"."Business Group Id", VALUEOF(NQ_SESSION.HR_ORG) FROM HR
Please help me for implementing the data security after the EBS-OBIEE integration..
For populating HR_ORG variable by row wise initialization:
SELECT DISTINCT 'HR_ORG',TO_CHAR(SEC_DET.ORGANIZATION_ID)
FROM
SELECT
'HR_ORG', ASG.ORGANIZATION_ID
FROM
FND_USER_RESP_GROUPS URP
,FND_USER USR
,PER_SECURITY_PROFILES PSEC
,PER_PERSON_LIST PER
,PER_ALL_ASSIGNMENTS_F ASG
WHERE
URP.START_DATE < TRUNC(SYSDATE)
AND (CASE WHEN URP.END_DATE IS NULL THEN TRUNC(SYSDATE) ELSE TO_DATE(URP.END_DATE) END) >= TRUNC(SYSDATE)
AND USR.USER_NAME = ':USER'
AND USR.USER_ID = URP.USER_ID
AND TRUNC(SYSDATE)
BETWEEN URP.START_DATE AND NVL(URP.END_DATE, HR_GENERAL.END_OF_TIME)
AND PSEC.SECURITY_PROFILE_ID = FND_PROFILE.VALUE_SPECIFIC('PER_SECURITY_PROFILE_ID', URP.USER_ID, URP.RESPONSIBILITY_ID, URP.RESPONSIBILITY_APPLICATION_ID)
AND PER.SECURITY_PROFILE_ID = PSEC.SECURITY_PROFILE_ID
AND PER.PERSON_ID = ASG.PERSON_ID
AND TRUNC(SYSDATE) BETWEEN ASG.EFFECTIVE_START_DATE AND ASG.EFFECTIVE_END_DATE
AND URP.RESPONSIBILITY_ID = DECODE(FND_GLOBAL.RESP_ID,
-1, URP.RESPONSIBILITY_ID,
NULL, URP.RESPONSIBILITY_ID,
FND_GLOBAL.RESP_ID)
UNION
SELECT DISTINCT 'HR_ORG',
ORGANIZATION_ID
FROM PER_ALL_ASSIGNMENTS_F ASG,
FND_USER USR
WHERE ASG.PERSON_ID = USR.EMPLOYEE_ID
AND USR.USER_NAME = ':USER'
AND TRUNC(SYSDATE) BETWEEN ASG.EFFECTIVE_START_DATE AND ASG.EFFECTIVE_END_DATE
AND ASG.PRIMARY_FLAG = 'Y'
) SEC_DET
Thx!

Duplicate post see Re: obiee-ebs data security integration

Using Data Security under Functional Developer / User Manager

Has anyone succesfully carried out any Data Security policies in Oracle Apps. I would like to get details on this.
Thanks in advance.

Actually the other scripts on the http://www.petefinnigan.com/tools.htm site seem to do the trick where you can check for who has DBA and who has SELECT ANY TABLE.
The next questions is .... what other privs should I be concerned with? Just want to make sure I am checking for all possibilities of access to a particular object.

SOAP - Not Receiving Response (Using WS-Security)

Hi All,
I have a scenario where XI is invoking a web service with an external party (using receiver SOAP Adapter) and expects a response message. Unfortunately I am not receiving the response message nor any error messages.
I am using WS-Security so I sign and encrypt the data before sending, additionally when sending the data it is sent over HTTPS, which makes debugging very difficult (i.e. cant use packet sniffer)
To try and debug the situation I have got XI to send to a local server over HTTP (knowing this will fail with the response message) but since XI does the HTTP POST and I have a packet sniffer running I can get the request payload that XI sends. I then send this myself from my own machine (not from XI) to the external party's webservice using debugging tools and I receive a valid SOAP response from the external web service.
I just cant figure out why XI is not receiving the response, in the message log the last lines I have are:
03.08.2007 23:24:48 Success SOAP: apply Web Services Security...
03.08.2007 23:24:48 Success SOAP: Web Services Security applied.
When checking the message the QoS is set to BE, and as far as I know everything is set right I just cant figure out why there is no response in XI
Any help would be appreciated
Thanks

For anyone who is also experiencing this issue I logged a note to SAP and have received a response.
It appears that in the WS-Security header on the response message from the external party they are including a "SignatureConfirmation" node. XI doesn't understand the signature confirmation on a response to a synchronous request. In the XI trace logs you can see the request was received with a HTTP 200 OK but nothing happens with the message from here, the request message will remain on delivering for many hours...
SAP advised that a patch will be released which is what I am waiting on, or the alternate solution is to get the party sending the response to not return a SignatureConfirmation node back (unfortunately the party I am communicating with were unable to do this)
Hope this helps someone!
Chris

Data security for multiple data sources

Dear BO guru's,
I am struggling with a brainbraker on authorizations on Universes since quite some time.
I am not a BO guru so hopefully someone can help me with this.
I (more or less) know the concept of data security in BO: users can be restricted on data level in (mainly) two ways:
1) with roles in CMC and with restrictions in Universe Designer.
OR
2) with a DB table that contains all authorized values per user and per field (i.e. John can see data for country UK)
The first is easy to set up, but hard to maintain.
The second is difficult to set up, but very flexible.
Now here is the problem...
Supporse your BO server is connected to different source systems (i.e. an SQL server, an Oracle server...) and you want only one universe to get data from all systems at the same time and display it in one report.
If I am not mistaken, this means we need a data federator.
...My questions:
1) Is there a possibility to do this without a data federator (but still have one universe to build my report or dashboard on)?
2) Where do I keep the table with authorizations for the users? Is that a database of the BO Enterprise server, a seperate data base, or in a table of one of the source systems (SQL, Oracle...)?
As this questions keeps me busy since long time, I would be very grateful to have your help.
It seems hard to find information on this.
Thanks a lot in advance!
UniverseDummy

1) Is there a possibility to do this without a data federator (but still have one universe to build my report or dashboard on)?
Apart from the Data Federator, you can either use an ETL tool to load your data into a single Datawarehouse or wait until XI 4.0
2) Where do I keep the table with authorizations for the users? Is that a database of the BO Enterprise server, a seperate data base, or in a table of one of the source systems (SQL, Oracle...)?
If you are going to use the Data Federator then you can create the table in one of your source systems and add it as a data source in your DF project.
Regards,
Stratos

IIR Filtering and response .vi: Butterworth filter magnitude response depends on sampling rate -why?

Hi folks,
I am not expert in filter design, only someone applying them, so please can someone help me with an explanation?
I need to filter very low-frequent signals using a buttherwoth filter 2. or 3. order as bandpass 0.1 to 10 Hz .
Very relevant amplitudes are BELOW 1 Hz, often below 0.5 Hz but there will be as well relevant amplitudes above 5 Hz to be observed.
This is fixed and prescribed for the application.
However, the sampling rate of the measurement system is not prescribed. It may be between say between 30 and 2000 Hz. This will depend on whether the same data set is used for analysing higher frequencies up to 1000 Hz of the same measurement or this is not done by the user and he chooses a lower sampling rate to reduce the file sizes, especially when measuring for longer periods of several weeks.
To compare the 2nd and 3rd order's magnitude response of the filter I used the example IIR Filtering and response .vi:
I was very astonished when I the found that the magnitude response is significantly influenced by the SAMPLING RATE I tell the signal generator in this example vi.
Can you please tell me why - and especially why the 3rd order filter will be worse for the low frequency parts below 1 Hz of the signal. I was told by people experienced with filters that the 3rd oder will distort less the amplitudes which is not at all true for my relevant frequencies below 1 Hz.
In the attached png you see 4 screenshots for 2 or 3 order and sampling rate 300 or 1000 Hz to show you the varying magnitude responses without opening labview.
THANK YOU for your ANSWERS!!!
chris
Solved!
Go to Solution.
Attachments:
butterworth-filter-differences.png ‏285 KB

Hello Lynn,
thanks for the answer. You are right that there are few points "behind" the curve in the graph, see png.
However, this is the filter response which Labview (2009) provides to me directly out of the "IIR Filter for 1 Channel. vi" in the "filter information" output cluster. Where up to now I do not know how to influence it - apart from adjusting the input parameters "IIR filter specifications". OK, I assume I have to gain more knowledge of this. The curve of the magnitude resonse dies not change when I change the number of samples of the input signal of the signal generator, only wehn I change the sampling rate.
I used directly the example vi from Labview with the name indicated in my first post "IIR Filtering and Response.vi".
So I assumed that everybody has it in his/her examples shipped with LV and it is not necessary to post it.
I just adjusted the size of the diagram of magnitude response to see the curves better as you see in the attached vi.
So I did no changes to the vital parts of signal generation and filter of the example. The screenshots are like they come from the example when using the option "one waveform" where I as user assume that this which is behind is quality-controlled by NI.
I was also astonished that the filter magnitude response is different to the one I copied out of graphs 1 year ago - but I unfortunately cannot reconstruct which example I used there...
Thanks for any further comments
chris
Attachments:
IIR Filtering and Response_CH.vi ‏55 KB
butterworth2nd_order_bandpass_0p1to10Hz_mag_response.PNG ‏18 KB

My iMessage for my Macbook Air is not working. It says no delivered with a red ! next to it. I have tried serval different options on trying to get it to work to include logging out of iCloud and checking my date and time. I have done about everythin

My iMessage for my Macbook Air is not working. I have updated everything. My system is running on OS X Yosemite Version 10.10. When I go to send a message, it says no delivered with a next to it. I have tried serval different options on trying to get it to work to include logging out of iCloud and checking my date and time and updating FlashPlayer. I have done about everything I can think of. Any help would be greatly appreciate!

Why start a new and very similar thread to your other one which you have not responded to (have you read the replies?)
I suggest that no response is made to this duplicate thread.

DBAs and responsibility in data security

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