Question E900 router with ip cameras no bandwidth ?

[Pachi_Mc]

Hi, i have a router e900 300mbps and 2 IP cameras using rtsp with 2mbps (and limited with QoS too), my wifi speed is 100mbps of download and 25mbps of upload, the problem is that i don't have bandwidth and i am not sure why, i run a speed test and i am getting 10mbps and 2mbps (i am next to the rotuer and only the cameras connected), could this be a faulty router ?

 

[kanewolf]

yes i know, so it would be working half speed + 1 antenna of 4 right ?
cameras are old dcs 936l

Nothing about a new router will fix the interference you said exists back in post #5. Your performance may still be poor because of the competing WIFI signals.

 

[Pachi_Mc]

Nothing about a new router will fix the interference you said exists back in post #5. Your performance may still be poor because of the competing WIFI signals.

yes I am not referring performance downgrade to the interference, i am trying to understand how the mbps are split between types of antenna and devices

 

[kanewolf]

yes I am not referring performance downgrade to the interference, i am trying to understand how the mbps are split between types of antenna and devices

They are split in time. Not by antenna (other than 2.4 and 5Ghz). So three fully active 2.4Ghz devices split the bandwidth by 6 at best. A slow device can make the available bandwidth lower than the spec and then that lowered bandwidth is split by 6.
In your original case, 2 cameras and one phone trying to view RTSP streams from the cameras. RTSP is done with UDP so there is minimal acknowledgements.
(Time sequence)
Cam1 transmits 1500 bytes of data and headers to the router (Cam2 and phone have to wait)
Router transmits 1500 bytes to your phone (Cam1 and Cam2 have to wait)
Cam2 transmits 1500 bytes to router (Cam1 and phone have to wait)
Router transmits 1500 bytes to phone (Cam1 and Cam2 have to wait)
Phone transmits NTP request to router (Cam1 and Cam2 have to wait)
Cam1 transmits 1500 bytes to router (Cam2 and phone have to wait)
Router transmits 1500 bytes to phone (Cam1 and Cam2 have to wait)
Router transmits NTP data to phone (Cam1 and Cam2 have to wait)
...
...
...

 

[Pachi_Mc]

They are split in time. Not by antenna (other than 2.4 and 5Ghz). So three fully active 2.4Ghz devices split the bandwidth by 6 at best. A slow device can make the available bandwidth lower than the spec and then that lowered bandwidth is split by 6.
In your original case, 2 cameras and one phone trying to view RTSP streams from the cameras. RTSP is done with UDP so there is minimal acknowledgements.
(Time sequence)
Cam1 transmits 1500 bytes of data and headers to the router (Cam2 and phone have to wait)
Router transmits 1500 bytes to your phone (Cam1 and Cam2 have to wait)
Cam2 transmits 1500 bytes to router (Cam1 and phone have to wait)
Router transmits 1500 bytes to phone (Cam1 and Cam2 have to wait)
Phone transmits NTP request to router (Cam1 and Cam2 have to wait)
Cam1 transmits 1500 bytes to router (Cam2 and phone have to wait)
Router transmits 1500 bytes to phone (Cam1 and Cam2 have to wait)
Router transmits NTP data to phone (Cam1 and Cam2 have to wait)
...
...
...

so a slow device would take more time to transmit and that would slow down all the next turns devices?
for example
Cam1 transmits 1500 bytes of data and headers to the router (Cam2 and phone have to wait - on 1 second)
Router transmits 1500 bytes to your phone (Cam1 and Cam2 have to wait - on 0.5 second)
phone have to wait and is slow down because cam1 is slow and it have to wait it ?

 

[kanewolf]

so a slow device would take more time to transmit and that would slow down all the next turns devices?
for example
Cam1 transmits 1500 bytes of data and headers to the router (Cam2 and phone have to wait - on 1 second)
Router transmits 1500 bytes to your phone (Cam1 and Cam2 have to wait - on 0.5 second)
phone have to wait more because cam1 is slow ?
and simultaneous speed is because it have at least 2 antennas, and the client have at least 1 receiver and 1 transmitter right?

More accurately, that it takes much more time to transmit the 1500 bytes. So the wait time is longer.

 

[Pachi_Mc]

More accurately, that it takes much more time to transmit the 1500 bytes. So the wait time is longer.

Thanks, so for clarity, the first problem is that the router have 2 antennas (150 mbps -each- 2 streams) but camera only 1 (1 stream available), so 300/2 (slowing all other devices) and because wifi is half duplex is 150/2, plus the overhead + interference reducing it, i am right? and also i should check if my camera have at least 150 Mbps, because if is slower could slow down even more the speed?

 

[bill001g]

When you look at the specs for your camera is says it only support 1x1 and 20mhz radio bands. That means the maximum it will use is 72.2 before you consider half duplex and overhead. The most you should expect is about 30mbps.
Since the cameras are fairly low resolution and they support h.264 data compression it should only need about 2mbps per camera. Make sure you use the H.264 compression option on your cameras.

You should still have no issues running 2 cameras. I will assume the device you have that the cameras send the data to is attached to your router via ethernet. You don't want the data sent a second time over the wifi when you have so little wifi bandwidth.

 

[Pachi_Mc]

When you look at the specs for your camera is says it only support 1x1 and 20mhz radio bands. That means the maximum it will use is 72.2 before you consider half duplex and overhead. The most you should expect is about 30mbps.
Since the cameras are fairly low resolution and they support h.264 data compression it should only need about 2mbps per camera. Make sure you use the H.264 compression option on your cameras.

You should still have no issues running 2 cameras. I will assume the device you have that the cameras send the data to is attached to your router via ethernet. You don't want the data sent a second time over the wifi when you have so little wifi bandwidth.

but cameras are over wifi no wired ethernet

 

[bill001g]

Maybe I was not clear. The cameras are sending the video output to some device. That device you want to have connected via ethernet.

 

[Pachi_Mc]

update: with the new router my wifi works fine on phone (only on 5ghz of course), and 2 cameras 1 mbsp each, first both camera worked but with some empty space on recorded viodeo of 10s approx (i think router switching client device), after a while only 1 worked but in the recorded video no empty space, the problem is the router is not giving bandwidth sometimes to second camera (the router is giving all traffic to only 1 camera),also is possible to record the video without empty spaces on both? or not possible because single user 2.4?

 

[bill001g]

The cameras should not really interfere with each other. There should be more than enough bandwidth for both to take turns and still have a lot left over.

But lets say there is some crazy limitation on the cameras since you now have you old router as extra use that as a second radio source. You would let one camera use the 2.4g radio on the new router and the second camera use the 2.4g radio on the old router. You would set the radios to different channels so they do not interfere.

So if we assume the old router does not have AP mode what you do is turn off the DHCP server in the old router. Change the lan IP to something that does not conflict with the other router or your other device. If the router used to use say 192.168.x.1 you could change the IP to 192.168.x.250. Then set the SSID to something different than the main router so you can force the connections where you want them. After that you plug a cable between the 2 lan ports of the routers. In effect you have added a new 2.4g radio to your main router.

Still it should easily work with both cameras on the same 2.4 radio.

 

[Pachi_Mc]

The cameras should not really interfere with each other. There should be more than enough bandwidth for both to take turns and still have a lot left over.

But lets say there is some crazy limitation on the cameras since you now have you old router as extra use that as a second radio source. You would let one camera use the 2.4g radio on the new router and the second camera use the 2.4g radio on the old router. You would set the radios to different channels so they do not interfere.

So if we assume the old router does not have AP mode what you do is turn off the DHCP server in the old router. Change the lan IP to something that does not conflict with the other router or your other device. If the router used to use say 192.168.x.1 you could change the IP to 192.168.x.250. Then set the SSID to something different than the main router so you can force the connections where you want them. After that you plug a cable between the 2 lan ports of the routers. In effect you have added a new 2.4g radio to your main router.

Still it should easily work with both cameras on the same 2.4 radio.

was thinking the same, using the old as AP for only 1 camera, the problem is i don't rlly want to use 2 routers, it should be enough for 1 mbps bandwidth each camera, not sure why is not, going to try tor reduce to 700kbps or something

 

[bill001g]

Cameras are almost as bad as wifi trying to figure out why they work or do not. They have so many options and tell so little about what they are exactly doing.

I would doubt it is pure wifi bandwidth issue unless for example the cameras where not compressing the data they where sending. So far I have not seen cameras you can say turn off h264.

It could be something related to how they are accessing the disk storage. That too is shared but like the wifi it would not be a simple bandwidth issue it would be more some file structure limitation.