Wikipedia:Reference desk/Archives/Computing/2012 October 5

= October 5 =

rtscp
i port scanned my pc, and port 554 is open. the port scanner says it's real time stream control protocol. netstat says the port is used by wmpnetwk.exe. i was wondering what it's for and how to close it. (i have windows7.) thanks, 70.114.254.43 (talk) 01:03, 5 October 2012 (UTC)
 * No offence but this is the kind of question that can really easily be answered by google. It took me about 30 seconds to google it and check it out, one of the results is even a youtube video called "How to Remove/Disable wmpnetwk.exe from your Windows 7 PC" . Vespine (talk) 03:51, 5 October 2012 (UTC)

sorry, i just get used to asking here, cause i can't normally find the info anywhere else. thanks for the tip. 70.114.254.43 (talk) 08:13, 5 October 2012 (UTC)
 * This link [] explains media sharing through WMP, which is what the process is for. These instructions show how to disable it: [] 209.131.76.183 (talk) 11:34, 5 October 2012 (UTC)

SSL/TLS sessions and http requests
I am trying to understand how an SSL session corresponds to HTTP requests. I understand fro the Transport Layer Security article that there is an initial negotiation and a "Resumed TLS" negotiation. If I perform an http request to a server, then obviously this must start with a full negotiation. The rest I am not clear on


 * If the response sends html and several images in one TCP session via HTTP keep-alive would these be sent without any negotiation?
 * If the response sends the images as separate http sessions would there be any renegotiation? If so full or resumed?
 * If later I click a link on the https page which requests another page and images on the server, will this use a renegotiation? If so is it a full handshake or a renegotiation?

I think that there probably is a renegotiation between the separate page requests to prevent "message repeat" attacks, but a definitive answer would be good. -- Q Chris (talk) 10:52, 5 October 2012 (UTC)


 * SSL/TLS doesn't understand HTTP at all. It just provides a byte stream like TCP's that can be used by HTTP or any other protocol. After the first connection to a particular IP address, if both ends have cached the shared secret that they negotiated the first time, a later connection can reuse that secret. That's "resumed TLS". Renegotiation is something else: it means agreeing on a new shared secret for an already-open connection. This can happen at any time and HTTP isn't aware of it at all. The answers to your questions are 1. yes; 2. yes, a new connection (not renegotiation), probably resumed; 3. yes (new connection) or no, and resumed or not, depending on whether the keep-alive connection has timed out and whether the cached TLS session information has been discarded by the client or server. -- BenRG (talk) 15:23, 5 October 2012 (UTC)


 * Thanks. I understand that SSL doesn't understand http, but I was wondering whether the browsers and/or servers would understand SSL and issue a "resume handshake" between each element downloaded in a persistent connection using keep-alive. Thinking about it there is no need because replay data could not be inserted during a session anyway. -- Q Chris (talk) 16:41, 5 October 2012 (UTC)

Stripping Javascript from PDF files
I have several hundred PDF files each of which have some Javascript in them. It's not a malware issue; it's the result of using Google Doc's "print" function to cache PDFs whose original files have ben deleted (clicking "Print" causes the original PDF to open again, off of Google's servers, but with a little "please print on opening" Javascript). It's annoying to me and the prospect of going over each one manually in Acrobat to delete the Javascript is, well, boring-sounding.

Is there any tool out there (either Mac or PC would be fine) that can go over the PDFs, just delete the Javascript automatically, and re-save the PDF? pdftk doesn't seem to do this. I have Adobe Acrobat but there doesn't seem to be a way to remove Javascript in a batch way (you can execute Javascript in batches, but not remove or edit it). I could probably use ImageMagick and/or pdftk to extract every page from the PDF and then re-compile them into a new PDF, but that seems like a really clumsy way to remove a single line of code, and one prone to producing huge files.

Any thoughts? --Mr.98 (talk) 16:03, 5 October 2012 (UTC)


 * Ah! I found a way to do it with pdftk. It's not as hard or clumsy as I thought:
 * pdftk myPDF.pdf burst output myPDF--%02d.pdf
 * pdftk myPDF--*.pdf cat output myPDF.pdf
 * del myPDF--??.pdf
 * Basically this just strips the PDF to individual pages, then recombines them again in order. Works reasonably fast even for big PDFs, doesn't add anything to the file size overhead (in fact, produces slightly smaller files, probably because of the removal of the JS and other meta junk). Easy to batch. The last line produces an annoyingly cryptic DOS error ("the parameter is incorrect") but works nonetheless. (The latter error may be related to the fact that I'm doing it on a shared folder in VirtualBox.) Thanks for being my rubber duck... --Mr.98 (talk) 16:19, 5 October 2012 (UTC)

When are pirate copies of films available?
When the movie is released in the form of DVD or when it's still in the theaters (they get digital copies nowadays, I suppose). OsmanRF34 (talk) 20:04, 5 October 2012 (UTC)


 * Sometimes before they're even in cinemas, having been extracted from screeners. -- Finlay McWalterჷTalk 20:06, 5 October 2012 (UTC)


 * pirated movie release types ¦ Reisio (talk) 02:14, 6 October 2012 (UTC)

Need a USB cable for old portable harddrive
http://i.imgur.com/19uRe.jpg

I lost the original, however I'm unsure what I need to get. Hopefully it's something cheap that's available from Monoprice? It's a Seagate GoFlex FreeAgent 500GB. Eisenikov (talk) 22:12, 5 October 2012 (UTC)
 * I can't see the image (on a ridiculously slow 3G connection), so please ignore this if it is not relevant, but if I recall correctly the GoFlex range has a SATA connector that had various different output types. Assuming that the image linked does show a SATA header, Seagate sold their own one-piece connectors with a chip inbuilt for this model (although it should work with any SATA drive). Otherwise there are lots of boards out there with mini or standard-B type connectors. — cdwn 23:43, 5 October 2012 (UTC)
 * The picture seems to show a Micro-B USB 3.0 connector to me. If I'm right you could just likely use a standard micro-B cord but be limited by the USB2.0 speed (which despite the theoretical limits is generally quite slow with mass storage devices, something like 20-30MB/s) or get a USB 3.0 and go at close to the raw HD transfer speed. Of course if you don't have a USB 3 port on the computer you plan to connect it do you might as well just use a standard microtype B USB cord if you have one (e.g. from a phone, digital camera, GPS), if you do need to buy one it may still be worth investing in a 3.0 since the price is unlikely to be much different and you may use it in the future (unless you want to the microB for something else although to be honest given the price and the increasingly common use it's probably worth having at least one spare of each handy). However I could be wrong, it seems a bit strange to have USB 3.0 on an old HDD. I do believe cdwn is correct that the GoFlex does have changable output types so it's possible someone put a USB 3.0 adapter on it for some reason. Note however my impression is the interface adapter connection is proprietary and not a standard SATA connection (or eSATA) although it's possible this is just with the 3.5" line. (The physical HDD likely has a standard 2.5" SATA connection but this isn't what is exposed to the changable adapters.) Nil Einne (talk) 07:02, 6 October 2012 (UTC)
 * If this page is correct, you won't be able to use anything except an actual GoFlex cable, because those cables have special circuitry built into them. They are not simply USB connectors. Looie496 (talk) 00:29, 7 October 2012 (UTC)
 * Actually if you read the comments, I believe you're mistaken. While the GoFlex does put the circuitry in the interface adapter the OP appears to have an interface adapter connected. The interface adapter is sometimes called a 'cable' because for whatever bizzare reason, Seagate chose to hardwire the cables for a number of adapters but as per the comments, they (thankfully IMO) did not do so for USB. Per the OP's picture, it looks a lot like they do have an interface adapter connected, in particular a USB 3.0 one which as I mentioned above is exposing a microUSB B socket (like from ).
 * However per that source and others like, , it seems that I was partially mistaken above, the GoFlex (as does the GoFlex Desk ) does in fact simply expose a normal (internal) SATA and power socket which is what the interface adapter connects to so in a cinch you could simply connect it to an internal connection (on a desktop, it's unlikely to be worth it on a laptop) as suggested by cdwn (of course you will still need an internal SATA cable and a free or freeable SATA port and power), or for that matter any vendors SATA to whatever adapter (provided they aren't physically blocked).
 * This does further suggest they have some sort of adapter connected as what's showing in the photo is not SATA+power sockets.
 * Nil Einne (talk) 03:37, 8 October 2012 (UTC)

Yes, there's indeed an adapter connected to the thing that leads to a long rectangle slot. However, I only want a simple cable to recover the files. I ordered this from eBay: it was free with eBay bucks so no big deal if it doesn't work (which I doubt). Eisenikov (talk) 14:42, 9 October 2012 (UTC)

http://www.ebay.ca/itm/USB-3-0-male-Micro-USB-Super-Slim-Flat-Cable-external-Hard-Disk-50cm-/130739907107?pt=US_USB_Cables_Hubs_Adapters&hash=item1e70b4aa23#ht_1977wt_1163


 * Yes that should work. Nil Einne (talk) 04:36, 10 October 2012 (UTC)

As an aside chaps, it's normally quite easy to remove portable hard drives from their cases and either directly connect them to internal drive cables in your PC or more easily use a USB to drive cable designed to connect to an drive's IDE or SATA ports (together with a mains adaptor with power cables for IDE / SATA drive power connections) Just a thought! Quintessential British Gentleman (talk) 20:04, 12 October 2012 (UTC)