POE Switch Uplink?

[catseyenu]

I'm new to POE and am unclear on how they work.
I have a Hikvision 8CH DS-7608NI-SE/4P (4 POE ports).
If I keep it I'll need another POE device for anything over 4 cameras.

1. Do all POE switch ports function as potential uplinks to my network?
Looking at the TRENDnet TPE-S44 Unmanaged Switch for example.
http://www.newegg.com/Product/Produ...56229&cm_re=poe_switch-_-33-156-229-_-Product

4 x 10/100Mbps Auto-MDIX POE Ports (1~4)
4 x 10/100Mbps Auto-MDIX Fast Ethernet Ports (5 ~8)
Unmanaged
4 Port PoE Switch

Can anyone explain the difference between the 2 different types of ports?

Would a unit like this serve as well?
http://www.ebay.com/itm/151236976714

2. Running the Hikvision 3MP cams, will the POE switch need or benefit substantially from a gigabit POE switch or are the 10/100 switches okay?

3. I will most likely only need 1 or 2 cams attached through the POE switch.
Any recommendations on a reliable unit with bang for buck in mind?

Thanks!

 

[fenderman]

1) Yes any port will act as uplink.
2) only 4 ports supply power POE. The other 4 are non powered standard Ethernet ports.
You dont want that ebay item, it is a passive poe injector not a poe switch.
3)With 4 cams you should be ok with 10/100. The cams themselves are only 10/100. When you load too many cams you clog bandwidth so generally with more than 4 or so (3mp) you would need at least a gigabit uplink (some 10/100 switches have gig uplink). Having the actual switch be gigabit is of no benefit.
The trendnet you linked to is a good choice. Another is this unit by zyxel, which is preferred by some like @networkcameracritic because it does not use a power brick which makes for a nice clean install and it is very reliable.
http://www.amazon.com/ZyXEL-ES1100-...d=1403438238&sr=8-2&keywords=zyxel+poe+switch

 

[catseyenu]

Thank you, much appreciated fenderman!
FWIW, looks like the Rosewill RFS-108P is the same as the ZxXel w/ a $50 price point shipped from Newegg.

 

[pcmcg]

I use an injector like your ebay link. Of course you need a switch to go with it, but it does that job and lets you pick any switch branch and model, not just POE versions.

 

[catseyenu]

I use an injector like your ebay link. Of course you need a switch to go with it, but it does that job and lets you pick any switch branch and model, not just POE versions.

Thanks, something like that would do the trick if it came with a power supply.

Any idea what voltage power supply I'd need... they list 3 different voltages?
Edit: FWIW the Hikvision 2032's claim to use 7.5 watts w/ IR on.

Connect the power supply you need (48v for phones, most cameras, 24v for Ubiquiti or Mikrotik, 18v for Tranzeo or OpenMesh, 12v for other devices)...

http://www.ebay.com/itm/171141611868

 

[fenderman]

I use an injector like your ebay link. Of course you need a switch to go with it, but it does that job and lets you pick any switch branch and model, not just POE versions.

One of the issues with passive injectors is that the usable distance is much less, about 130 feet vs 330 with true poe. Another is that since the voltage supplied varies based in the distance and gauge of wire, you run the risk of all sorts of unexplained issues. It also takes up more room as you need two units and a bunch of patch cables between them. Depending on where they are being mounted that is a consideration. For a two camera setup like OP is doing, a regular poe switch is the way to go.

 

[networkcameracritic]

It's a cheaper way to go but what a mess of wires you'll have and I have a big mess with just 8 port switches, can't imagine not only doubling the wires, but it taking 2 outlets on my UPS.

 

[Shockwave199]

For eight 2mp cameras, which is less stressful on a network, poe switch to nvr or nvr with poe built in?

 

[catseyenu]

One of the issues with passive injectors is that the usable distance is much less, about 130 feet vs 330 with true poe. Another is that since the voltage supplied varies based in the distance and gauge of wire, you run the risk of all sorts of unexplained issues.

My longest stretch is under 50' & I'm using solid copper Cat6.

It also takes up more room as you need two units and a bunch of patch cables between them. Depending on where they are being mounted that is a consideration. For a two camera setup like OP is doing, a regular poe switch is the way to go.

2 units..., they only show one? (see attached pic)

View attachment 719

There is a GB switch with 4 empty ports already in place that I can use.

It's a cheaper way to go but what a mess of wires you'll have and I have a big mess with just 8 port switches, can't imagine not only doubling the wires, but it taking 2 outlets on my UPS.

It will have 1 wire coming from the camera that would be there anyway +1 patch going into the existing switch so it will only need one outlet on the UPS.

I'd love to grab a new 8 port POE giga switch but at over $150 I'm having trouble justifying the purchase when I can add 8 POE ports for under $50 to what I already have.
Am I missing something?

View attachment 720

 

[icerabbit]

Any reason for the white patch box?
Seems like one extra thing to secure, a few extra short cables, ...

What model & how much is that POE injector strip?
It might be handy, and allows one to repurpose an existing switch.

I just went with a $40 4POE 8port switch. Less cables & interruptions to fidget with.

 

[catseyenu]

What model & how much is that POE injector strip?
It might be handy, and allows one to repurpose an existing switch.

I'm looking at WS-POE-8- 48 Volt 30 watt from here:

http://wifiqos.com/index.php

$45.70 shipped

The 4 port POE switch with 4 - 10/100 ports seem like a waste of 4 - 10/100 ports to me whereas the extra POE ports could be useful in the future.

 

[icerabbit]

True 8port with 4POE may be not be ideal and maybe wasteful, depending on the number of cameras needed and the length of the runs, but it seemed cheaper than a dedicated 8POE or some 4POE or a bunch of individual injectors. You still get 4 POE and one is uplink. So what if 3 are dormant

In my scenario with long runs, the camera kit is going to be split in half, into two zones each with an 8port 4POE from a reputable brand, serving probably 3 cameras and likely a wifi access point too. I'm getting tired of wifi cutting out and my mobile data being used up while in the garage or outside.

 

[Spaceboy]

For eight 2mp cameras, which is less stressful on a network, poe switch to nvr or nvr with poe built in?

If you were doing 16 3mp cameras @ 20+FPS... would you go with a dahua with a built in POE switch (7816p series or utilize 8 ports of a 5800 series) or just go with a non poe series nvr and an expensive cisco 300 switch( http://www.amazon.com/Cisco-SG300-2...d_sim_e_3?ie=UTF8&refRID=17ER21HE58XVD1K6TW5P )? or Zyxel switches? I have verizon fios at 35Mbps, so I wanted to take advantage of that ... I know it would be less expensive to get a 16ch poe nvr unit, but I don't know if it's the best way to go or if there's a less expensive way to not bottleneck the system anywhere....

I was going to go with around 4 of those hikvision cubes and then the rest dahua 3.8mm's if there won't be compatibility issues.

 

[pcmcg]

I'm looking at WS-POE-8- 48 Volt 30 watt from here:

http://wifiqos.com/index.php

$45.70 shipped

The 4 port POE switch with 4 - 10/100 ports seem like a waste of 4 - 10/100 ports to me whereas the extra POE ports could be useful in the future.

Yup, that is the one I have, but I got the 120W power supply. I have not heard of any distance issues, but I don't plan on having any runs more than 100ft either way.

 

[pcmcg]

Also, can anyone can explain why the active POEs will get more distance? Does the "active" injector actually output >48V to compensate for the voltage loss?

 

[wifiqos]

Also, can anyone can explain why the active POEs will get more distance? Does the "active" injector actually output >48V to compensate for the voltage loss?

We have a web page to answer the question about distance with PoE. http://wifiqos.com/poe-calc.html there you can input the voltage, and it will calculate the loss in the ethernet wire over distance.

Using that tool, one can see that it is the Loss in the cable that determines the max distance - not active vs passive. The loss in the wire is effectively the current squared times the distance at about 2.8 ohms per 100 ft. The loss at 48 volts is 16 times less than at 12 volts.

If you use a camera that has no PoE - like a 12 volt camera with passive injectors and splitters - the max distance is about 90 ft at 8 watts beyond that the loss is extreme and the supply voltage is unstable. 5 volt camera have a very short passive extension range - about 10 ft.

If your camera spec says "12v, PoE" then it uses 12v from a wall-wart and 48v from the ethernet cable. If it says "12v, 802.3af" - 802.3af is 48v by default - so the math is the same. The only popular PoE devices that do not use 48v PoE are Ubiquity and Mikrotik. So use a 48 volt power supply with the passive injector. Multiply the power each camera needs (usually 6 to 8 watts) times the number of cameras - then use a power supply with that rating. So 6 cameras at 7 watts is 42 total - plus line loss of about 10% - so use a 48 volt power supply with at least 50 watts.

There are some obscure 18v, 24v PoE devices - but their specs don't state 802.3af - if in doubt - ask your favorite electrical engineer! Customer service for most cameras do not understand PoE ! Because of this, I am building a database of devices and PoE compatibility and power consumption.

802.3af differs from passive PoE at 48v in only one respect. an 802.3af switch will only provide power if the client device is 802.3af also. So you can have an 8 port PoE switch - and plug in a laptop and there will be no power. A passive injector, like the 8 port shown above - or 12 or 16 port - have power on all the time - so you want to connect this to PoE devices only.

The basic concept of a midspan injector - active or passive - is to add PoE to your favorite, existing, non-PoE switch or router. They are a great way to add PoE ports when you run out of power. And you can provision the power supply to the wattage total you need. A midspan injector does not modify the TCP packets in any way - so vlans, QOS and other things pass unchanged. For 4 PoE ports, an 8 port PoE switch with 4 PoE and 4 non-PoE are popular. As the number of PoE ports increases, the costs increase rapidly, making an 8 or 12 or 16 port passive PoE injector more cost effective.

For those 5 volt and 12 volt non PoE cameras (like Foscam etc) - there are PoE to 5 volt and 12 volt DC-DC converters that provide regulated 5 or 12 volts directly at the camera - allowing distances way past 300 ft, eliminating the effects of line loss.

We have never seen a camera that needs gigabit switch ports or CAT-6 or CAT-7. Note that most PoE switches and passive injectors are 10/100. If you want future proof, then gigabit passive injectors also exist, they are more expensive because power and data must share the same pins. In 10/100 passive - data is on pins 12 and 36, power is on 45+ and 78- .

Some cameras have heaters for cold weather - these heaters can take a lot of power, more than 802.3af allows. For this reason, PoE+ exists - it uses 56 volt injectors and all 4 pairs - reducing the loss by 2.5x .

Yes - I do design and manufacture passive PoE injectors, and provide tech support at http://wifi-texas.com since 2003

Best Regards
Murray

 

[catseyenu]

Murray, thanks for stopping by and helping with the POE education.

We have never seen a camera that needs gigabit switch ports or CAT-6 or CAT-7...

To be specific you are speaking about power and bandwidth, right?
Quality of video signal is, I believe, a whole 'nother ball of wax.

 

[wifiqos]

I am sure cameras exist at faster than 100mb/s data rates - say in raw mode and 30 frames per second - that is just 150k RGB pixels in raw mode to hit 3.3 mbit per image. But with compression in modern cameras so good, the bandwidth used for most applications is far below the raw data rate. So between the camera and the switch - we need far less than 100mb/s - so CAT-5e is just fine. Just be careful with Copper Clad Aluminum wire - that can be a disaster. The switch uplink is a different story.

 

[icerabbit]

Big thanks to Murray for the primer!

:star::star::star::star::star:

We have never seen a camera that needs gigabit switch ports or CAT-6 or CAT-7. Note that most PoE switches and passive injectors are 10/100. If you want future proof, then gigabit

That's the route I am taking.

I have been positively surprised in first trials about the bandwidth needs per 3mp camera set to 1080p in h264 at average settings. I knew the cameras only link 100mbps, so, I know standard cat 5 / 5e + 100 switch are fine.

But, then comes the future, and who knows what it brings?

New - go cat 6. In a retrofit situation with longer lines, less separation / more interference, go with cat 6. It costs a bit more per box of wire, but not that much. The labor / effort is the same, and the higher cost. End to end solid cat 6 is peace of mind and something I figure won't have to be upgraded in my lifetime when it comes to cameras.

Switch. Limited installs with great compression aren't going to outgrow 100mbps, but beyond that with n-nn cameras, using higher quality settings, more megapixel cameras on the horizon, maybe more than one live viewing screen, maybe dual recording, etc. I figured to just go with a full on gigabit poe switch. The cost for a value model isn't that high; compared to a 100mps switch with gigabit uplinks. Either works, but one can make the investment once for the next decade. A full on gpbs one certainly has the headroom to handle x gbps easily, a dozen cameras without running out of power, and has gigabit links for the storage pc / nas, network router and wifi ap points. No need to uplink through something else. In fact, one can plug a few pc hard lines in too and not need a regular old switch. Whichever combination works directly.

If or when 10gbe comes to computers, routers and access points near us - if it comes with a low enough price points to satisfy higher bandwidth media needs, faster flash based central storage within the home etc - then I figure good cat 6 should be able to handle it, provided the runs aren't too long, etc.

 

[wifiqos]

One of the issues with passive injectors is that the usable distance is much less, about 130 feet vs 330 with true poe. .....

One thing to consider, is the electrical engineering difference between passive and 802.3af or "true PoE". It is about the voltage, not passive vs "true". A Hikvision or such camera can operate at either 12v from a wall wart, or 48v from the ethernet cable. If you try to extend using the 12 volt input, then the range is limited to about 60 ft before the voltage drop causes it to stop working. You can simulate the loss here http://wifiqos.com/poe-calc.html . At 48 volts, the current is 1/4 as much, therefore the loss in the wire is 1/16 as much ( I^2 * R ) and for this reason, passive or 802.3af at 48 volts operates to 328 ft (which is the limit for Ethernet signals). So passive at 24 volts or higher is NOT limited, either for voltage or data. People with extra switch ports ( like on a router, or non-PoE ports on an NVR) use a PoE injector like http://find-a-poe.com/product/WS-POE-8-48v60w/ because they already have enough switch ports and just need to add power to them.

A 48 volt passive or 802.3af switch supplies 48 volts either way, the difference is that 802.3af will only apply power if the client device is 802.3af, so you can plug non-PoE devices into any port on a 802.3af switch without problems. Since the voltage is the same, the distance is the same. Some passive PoE switches can be used as PoE repeaters - to extend the signal beyond 328 ft - since the switch is powered from the Ethernet, rebuilds the data, and supplies power and data for the next 328 ft length.

Another consideration for using 48v instead of 12v, is that the CAT-5e and CAT-6 sold at Home Depot and elsewhere, isn't copper. It is a Cu/Al alloy with higher resistance, this further limits the distance ( in the case of a foscam 5v - no more than 10 ft). At 48 volts, that loss is insignificant. A PoE Tester can show the actual delivered voltage, if someone wants to find out of their wire is Cu or Cu/Al.

All this is explained in this video https://www.youtube.com/embed/mPvDJvFu3rs