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April 7

Can I use crappy networking equipment with 4K IP camera?

I have a supposedly 4K IP camera connected to my network and when I view the image on my PC and open Windows Resource Monitor, I see a receive rate between ~820-880 KB/s. Does that mean that any old crappy network cabling/equipment will do just fine? Like a 10/100 network switch and Cat 5 cable? I need to waterproof an RJ45 connection so I have to either a) cut the end off a cable and solder it back or b) cut the end off a cable and attach a new RJ45 plug. If I'm right that a crappy connection is okay, then the "impedance bump" of a soldered ethernet cable will be okay, right?

Incidentally, is this rate of data what you'd expect for 4K video (compressed with H.264) at 15 FPS?

Screenshot of Resource Monitor

Thanks 78.149.180.132 (talk) 02:16, 7 April 2019 (UTC)[reply]

As a rule of thumb I assume a 10 fold difference between B/s and bps which allows for framing etc. So superficially your 850 kB/s works out at 8.5 Mbs which agrees with the network graph on your screen shot. However there are a number of other factors to consider. If anywhere along the chain you have a poor cable or connection then you may get noise or dropped bits. Not a problem for TCP, it just requests a resend. However a resend more than doubles the bandwidth consumed (send - NACK - resend), so a noisy cable can reduce your bandwidth dramatically. For this reason, if no other, your option (b) is probably better. The "impedance bump" is where you can get reflections which lead to the aforementioned dropped bits and noise.

A 10/100 switch may be adequate if it is just connecting two cable segments together, but some of the cheaper ones cannot handle full speed on all ports. The internal switching just is not up to it. Again, a rule of thumb, assume that a 10/100 domestic switch can handle 100 Mbs total, any more and it may start buffering or dropping packets, which will require a TCP resend with consequent loss of bandwidth.

I've assumed TCP, but if your application/camera use UDP you do not get the resends, the data is just lost and the picture degrades. Martin of Sheffield (talk) 10:11, 7 April 2019 (UTC)[reply]

Duplex LC connector with SFP module

Please help I want to know what will I get or should get if place an order of 1 unit 1000Base LX SM mini gigabit transceiver such as D-Link DEM 310GT.It seems from the datasheet that a duplex LC connector should accompany the the main SFP module according to the product description and technical features listing of D-Link DEM 310GT as mentioned in The datasheet link is "http://www.dlink.co.in/pdfs/products/DEM-310GT/DEM-310GT_ds.pdf".Am I wrong?Wrogh456 (talk) 15:17, 7 April 2019 (UTC)[reply]

You will get what you see in the bottom left of the picture at the top. It will be a sfp module with a rubber plug. It will have the duplex socket. There will be no fibre optic lead with it. Graeme Bartlett (talk) 21:24, 8 April 2019 (UTC)[reply]

Agreed I understand that the item generally comes as you described in this particular case strictly going by the data sheet "http://www.dlink.co.in/pdfs/products/DEM-310GT/DEM-310GT_ds.pdf" in two places first in the header line and then feature and component listing along with other features or components like melt enclosure for lower EMI and in the product description headline it is witten as follows "D-Link Gigabyte Interface converters are are tranceivers that connect..The fiber optic transceivers have standard duplex LC connectors for connection compatibility".Strictly with refrence to this particular make and model is it wrong to expect that D-Link will ship standard duplex LC connector with the SFP module as per the datasheet even if there no SFP patch cable just the loose connector.Is my argument technically flawed.I am agreeing cent percent with your generic version for example in D-Link USA /Australia datasheet it is mentioned that the SFP module has LC type interface option of so no duplex LC connector should expected to be shipped with SFP package in USA/Australia/UK etc as applicable matching with the stipulated technical specs assured in the respective datasheet whereas since in D-Link India datasheet it is described this way hence my question is it technically wrong to expect "standard duplex LC connector" according to D-Link India datasheet product description.Same main product in different countries are known to be shipped with different accompanying free accessories depending of marketing decision by companies.My question is in relation to this particular model and make in India market is it technically wrong to expect the thing called standard duplex LC connector with DEM 310GT — Preceding unsigned comment added by Wrogh456 (talk • contribs) 07:10, 10 April 2019 (UTC)[reply]

The connector is the hole in the SFP module. You will not be getting any extra patch lead. As I said you will have to have more information to get a patch lead. It is not "technically" wrong, but different vendors sell different products. If you want a whole working system then you can pay an integrator much more money to put the whole system together, ie a "solution". Graeme Bartlett (talk) 12:17, 10 April 2019 (UTC)[reply]

Rear camera does not work after changing motherboard

I had the android phone (Huawei Y5 II) repaired by customer care. After replacing the mother board I came to home and to my surprise, I found that camera is in selfie mode. I tried to switch the rear camera by pressing the "switching" icon. But it does not work. I checked the other options with no results. Did technician forget to assemble properly ? What might be possible cause? Thanks.--103.231.162.134 (talk) 16:05, 7 April 2019 (UTC)[reply]

You should ask the technician or the customer care, I think. Ruslik_Zero 18:15, 7 April 2019 (UTC)[reply]

April 9

How to retrieve phone contacts from google drive or gmail. ?

Hello there, I had the motherboard of android phone (Huawei Y 5II) replaced by customer care technician. Before replacing, technician helped me to moved all files to google drive. I have recovered all files except contacts. I have tried to retrieve them from gmail and google drive with no results. The only thing I retrieved a excel file named, "contacts.csv". But when I opened the file there are no contacts except random words like, Name, Initials, name suffix and some other words. How can I get back contacts? Would you be open minded to help me out ? Thanks in advance. --103.231.162.134 (talk) 18:17, 9 April 2019 (UTC)[reply]

Did you import the csv into Excel? A csv file is just comma separated variables, so it should load into any text editor or word processor. If you cannot read it in a text editor then it is probably corrupt unless it was saved in some special format designed to load back into the phone. Your technician might know. Dbfirs 19:13, 9 April 2019 (UTC)[reply]

Yes, it's a csv excel file. When I open it, it only shows headlines such as, name, title, family name etc. But no number at all. How can I get back my numbers ?--103.231.162.134 (talk) 12:30, 14 April 2019 (UTC)[reply]

April 11

Closing CMD prompt while a process is running

Hello, I was just running a DISM.exe scan on Windows 8, which is done via command prompt. The percentage progress etc is shown in the cmd window. I accidentally closed the cmd window. Does that stop the process, or if not, how do I check the process’s progress? Thanks Amisom (talk) 20:48, 11 April 2019 (UTC)[reply]

Yes, when you run a program within a command prompt, note how the command prompt's title bar changes to show the name of the exe running within it. This is the same as running a dos-like exe separately and having it flash up a command prompt box then disappear as it finishes. With command prompt though, that same exe is running within the cmd.exe interpreter, but still has a path to the rest of the system. So if you close cmd.exe with a program running inside it, that program gets closed too. RegistryKey^(RegEdit) 04:44, 12 April 2019 (UTC)z[reply]

I am not sure that DISM.exe is a dos-like program. It is win64 application (in 64-bit system) and it does not run within cmd. Ruslik_Zero 20:34, 12 April 2019 (UTC)[reply]

You should be able to see whether DISM is still running using Task Manager. Mitch Ames (talk) 08:25, 14 April 2019 (UTC)[reply]

April 14