(5) 1-2MP cams on 10/100 switch?

[rkolb86 0]

It should work, right?

 

I'll be using 1 Vivotek IP7631 (2MP) and 3-4 IP8332 (1MP) on a 10/100 switch? I'll be using the at max resolution if it helps.

 

My guess is that it should work fine, but I feel I should ask the experts here.

 

 

I doubt it matters, but I plan on using 2 NICs inside my PC, one for internet access, the other for the IP cams.

 

 

 

Switching Capacity (Gbps): 3.2 Gbps

Switching Forwarding Rate (Mpps): 2.4

 

Thanks

[fa chris 0]

Vivotek claims to have a calculator for such things, but apparently they've recently revamped their website and in the process managed to break all their links... so I have no clue where to find it. What's more disturbing is their cut sheets don't list bandwidth requirements.

 

At max quality the IP8332's use less than a MB/Sec as long as you're using MPEG4 or H.264. With motion jpeg at max quality it's almost 4 MB/s...

 

The other camera uses less bandwidth at max quality, by only recording at 10fps (compared to 30fps for the IP8332).

[rkolb86 0]

Just to be clear, your numbers are in Megabytes per second, not Megabits per second?

[fa chris 0]

Just to be clear, your numbers are in Megabytes per second, not Megabits per second?

 

Yup.

[rkolb86 0]

So on a 100Mbps switch, i can achieve 12.5MBps on the link to the NVR.

 

5 cameras using MPEG4 will give me <5MBps...enough room for up to 7 (theoretically) more cams before I saturate that link (probably 5 cams additional with overhead)?

[ssmith10pn 0]

Someone has their bits and bytes mixed up. My 5mp Avigilons only draw 11.4 Mbps (Mega Bits Per Second) @ 5 frames per second.

My 1mp H264 cameras pull 1.0 Mbps at 5 frames per second. Actually more like .8

[rkolb86 0]

Not me.

 

Your 5MP cam would use nearly 1.5 MBps then.

 

 

Say your 1MP cam was 1Mbps @ 5fps, I'd guess that it would probably use about 6 Mbps [megaBITS] at 30fps (using a constant bitrate)...or 0.75MBps [MegaBYTES]

 

I think he stated that the 1MP Vivotek with h.264 would be a little less than 1 Mbps at 1200*800, 30fps (or whatever max resolution is)

 

 

Mb to MB...divide by 8. 8 bits in a byte....unless you're a HDD manufacturer who uses a decimal multiple system in order to legally mislead consumers

 

 

Am I missing something here? Did I do something wrong?

[ssmith10pn 0]

Why are we even talking about Mega Bytes?

 

The switch and cameras are rated in Mega Bits.

 

Your 100Mb switch will be fine.

[rkolb86 0]

lol...you should tell the hardware manufacturers the opposite! Back in the day, 100Mb was huge...who gives a **** about them these days?

 

 

The switches should be rated in MBps! 12.5Mbps and 125MBps for 100mbps and gigabit respectively.

 

 

That's good to know that each 1MP cam will prob be on the order of 1 Mbps.

 

If that is the case, I could probably hook up about 85 or so 1MP cameras to a 100Mb/s switch (assuming a **** ton of overhead)

[Soundy 1]

Keep in mind that if you're using a VBR (variable bitrate) codec, your stream is probably rarely going to actually be at that maximum rate. Depending on scene complexity, contrast, sharpness, movement, and a handful of other factors, it may only be a few kilobits at times, and unless all cameras are seeing movement all at once, your TOTAL bandwidth will be far less than the maximum you're planning for.

[ssmith10pn 0]

 

Don't be concerned until you see this.

 

[Korgoth Of Barbaria 0]

Keep in mind that not only 10/100 or 10/100/1000 parameter matters.

Check port buffer size on your switch, for megapixel cams it should be 190k or more.

My cilent was using D-Link 10/100/1000 10 port switch with 8x GeoVision BX120D (1.3Mpixel H.264, 30fps) - and there was some short "freezes" on video. This switch had 64k buffer, we changed it for fast ethernet Cisco SRW208 with 2 gigabit ports - and now video is smooth.

[ssmith10pn 0]

You have to dig deep into the specs of the switch and make sure the backplane bandwidth is equal to a total of all the ports. Less expensive switches are not.

Some only have enough bandwidth to carry one port at full load.

[Korgoth Of Barbaria 0]

You have to dig deep into the specs of the switch and make sure the backplane bandwidth is equal to a total of all the ports. Less expensive switches are not.

Some only have enough bandwidth to carry one port at full load.

 

Shouldn't it be "total of all the ports" x2?

[rkolb86 0]

Keep in mind that not only 10/100 or 10/100/1000 parameter matters.

Check port buffer size on your switch, for megapixel cams it should be 190k or more.

My cilent was using D-Link 10/100/1000 10 port switch with 8x GeoVision BX120D (1.3Mpixel H.264, 30fps) - and there was some short "freezes" on video. This switch had 64k buffer, we changed it for fast ethernet Cisco SRW208 with 2 gigabit ports - and now video is smooth.

 

This sounds like the issue is a function of a slow or bad switch (either CPU, Bus, cache speed,or processing algorithm), not the buffer size. Sure a larger buffer would help, but only until the buffer becomes full again and it starts dropping packets. If you were to theoretically enlarge the buffer of that D-Link, I bet the same issue would occur. (It was probably a low-end D-link...which is almost all of them)

 

 

 

 

You have to dig deep into the specs of the switch and make sure the backplane bandwidth is equal to a total of all the ports. Less expensive switches are not.

Some only have enough bandwidth to carry one port at full load.

 

Well that's easy:

3.2Gbps = 3200Mbps/16 ports = 200Mbps bidirectional = 100 Mbps in a single direction per port

(I originally did this calculation using the pps, a 64 byte frame size with a 20 byte interframe spacing, and a 8 byte preamble originally...but I won't subject you to a page of math)

 

 

I'll only be using up to 8 ports though because only 8 are PoE....with a 130W budget across the 8 ports.

Edited December 15, 2011 by Guest

[rkolb86 0]

If anybody cares, this is the switch I'll be using.

 

http://www.newegg.com/Product/Product.aspx?Item=N82E16833181164

 

 

 

It's specs are very good for what you pay for...a little over $100 for 10/100 and 8 PoE ports @ 16.25w per port.

It was actually cheaper than buying a standard switch and 8 PoE injectors.

 

 

 

I've used ZyXEL before for a VPN firewall as well as some ethernet-ADSL bridges. They are very reliable and their customer service was pretty good.

[fa chris 0]

Why are we even talking about Mega Bytes?

 

The switch and cameras are rated in Mega Bits.

 

Your 100Mb switch will be fine.

 

And storage is rated in Mega Bytes, which is often all you ever get from camera manufactures to figure out your bandwidth.

[rkolb86 0]

Keep in mind that if you're using a VBR (variable bitrate) codec, your stream is probably rarely going to actually be at that maximum rate. Depending on scene complexity, contrast, sharpness, movement, and a handful of other factors, it may only be a few kilobits at times, and unless all cameras are seeing movement all at once, your TOTAL bandwidth will be far less than the maximum you're planning for.

 

 

This is true, but I'm the kind of person who likes to be prepared for the worst case scenario.

 

If it glitches while the next door neighbor is throwing broken glass in the driveway again, I'm screwed

[amirm 0]

Guys, if you want to become super comfortable for bits and bytes of video (and audio), here is an article to get you there: http://www.madronadigital.com/Library/Audio%20Video%20Encoding%20Formats.html. I wrote it for audio/video people and not CCTV applications but most of it should be useful in this context too.