Network Bandwidth Crawling - please suggest a fix.

[magohn 0]

Hello all,

 

I have setup a CCTV network consisting of the following.

 

i-Catcher Console Software

Standalone PC for the CCTV

Linksys WRT54gL Router (DDWRT)

Linksys WRT54gL Client - Bridge (DDWRT)

2 Y-Cam Wifi Cameras (capable of 30FPS)

DLink 900 Wifi Camera

Axis 215 PTZ - E

 

All cameras are in 640x480 mode.

 

The system is setup with the 2 Y-Cams and the DLink connecting wirelessly to the router. The 215 and the PC running the i-Catcher software (that monitors all cameras), both connect wirelessly to the router/network via the "Client-Bridge" linksys.

 

All cameras are mounted outdoors except for the DLink that monitors the garage.

 

 

The issue is that camera FPS improve greatly at night time whereas thru the day the Y-Cams have low (0.5) FPS and sometimes drop connection all together. At night they get the full 10FPS.

 

I believe the issue is that the Axis is draining the bandwidth in color mode (daytime) and when it switches to night mode the other cameras have a chance to grab extra bandwidth. The Axis ALWAYS maintains a strong FPS no matter what time of day.

 

Am I missing something in regards to setup - I have the Y-cams dialed back to only 10FPS and the Axis set to 10FPS. The Dlink never gets above 2FPS.

 

I seems I should easily get 10FPS on all cameras no matter what time of day. From the same setup I can stream movies to the xBox in full-screen for a 52" TV.

 

Please suggest any ideas for improvement.

 

Thanks! Magohn

[Soundy 1]

I think you're on the right track, that the Axis is at least part of the problem.

 

The root of issue, though, is available bandwidth. At 802.11g, you've got *theoretical maximum* half-duplex 54Mbps available... to ALL wireless devices. Realistically, you're only going to see about half that for a continuous stream, so now you're down to 27Mbps, SHARED.

 

Your fix, quite simply, is to hardwire as much of the system as possible. You can dial back framerates to further reduce the "interference" but that's only a workaround.

[magohn 0]

I think you're on the right track, that the Axis is at least part of the problem.

 

The root of issue, though, is available bandwidth. At 802.11g, you've got *theoretical maximum* half-duplex 54Mbps available... to ALL wireless devices. Realistically, you're only going to see about half that for a continuous stream, so now you're down to 27Mbps, SHARED.

 

Your fix, quite simply, is to hardwire as much of the system as possible. You can dial back framerates to further reduce the "interference" but that's only a workaround.

 

Thanks Soundy. To test, I ran a 100ft CAT5 cable from the Axis 215 directly into the router and the whole system came back to life. Expected FPS returned and the network in general returned to being snappy.

 

I have decided to mount a Netgear switch in the garage and route CAT5 cable to any camera that I can. Luckily all my cameras will work in WiFi or cable mode.

 

Thanks again, magohn

[hardwired 0]

You might take a look at Ubiquiti's "N" rate stuff, for short hops, people are getting close to wirespeed on it.

[Soundy 1]

11n will improve things, definitely... even 11g gear sees a boost from it, but you still only get maximum speed and range between 11n devices. If wired network is an option (even a difficult one), wired is ALWAYS preferred for CCTV.

[hardwired 0]

11n will improve things, definitely... even 11g gear sees a boost from it, but you still only get maximum speed and range between 11n devices. If wired network is an option (even a difficult one), wired is ALWAYS preferred for CCTV.

 

I definitely agree, wireless is also my last choice, I use coax-ethernet adapters, Veracity ethernet extenders, DSL-type extenders, even free-space optics before wireless... But sometimes, it really is the only option.

 

My point was, if you're going to use wireless, use GOOD wireless... I use a lot of Ubiquiti stuff, either their complete units, or their mini-PCI, XR series cards in Mikrotik routerboards (there's a fun learning curve) to get reliable results.

 

I also do a spectrum analysis, and also propagation path modeling in Radio Mobile for longer hops. Takes a little more effort, but it's worth it.

[ak357 0]

11n will improve things, definitely... even 11g gear sees a boost from it, but you still only get maximum speed and range between 11n devices. If wired network is an option (even a difficult one), wired is ALWAYS preferred for CCTV.

 

I definitely agree, wireless is also my last choice, I use coax-ethernet adapters, Veracity ethernet extenders, DSL-type extenders, even free-space optics before wireless... But sometimes, it really is the only option.

 

My point was, if you're going to use wireless, use GOOD wireless... I use a lot of Ubiquiti stuff, either their complete units, or their mini-PCI, XR series cards in Mikrotik routerboards (there's a fun learning curve) to get reliable results.

 

I also do a spectrum analysis, and also propagation path modeling in Radio Mobile for longer hops. Takes a little more effort, but it's worth it.

 

What do u use as wi-fi analyser ?

 

Wi-Spy ?

UBIQUITI AIRVIEW2 ?

any other ?

Thx

[hardwired 0]

11n will improve things, definitely... even 11g gear sees a boost from it, but you still only get maximum speed and range between 11n devices. If wired network is an option (even a difficult one), wired is ALWAYS preferred for CCTV.

 

I definitely agree, wireless is also my last choice, I use coax-ethernet adapters, Veracity ethernet extenders, DSL-type extenders, even free-space optics before wireless... But sometimes, it really is the only option.

 

My point was, if you're going to use wireless, use GOOD wireless... I use a lot of Ubiquiti stuff, either their complete units, or their mini-PCI, XR series cards in Mikrotik routerboards (there's a fun learning curve) to get reliable results.

 

I also do a spectrum analysis, and also propagation path modeling in Radio Mobile for longer hops. Takes a little more effort, but it's worth it.

 

What do u use as wi-fi analyser ?

 

Wi-Spy ?

UBIQUITI AIRVIEW2 ?

any other ?

Thx

 

I use the Airview 2, and 9 (do quite a bit of 900MHz stuff), also Mikrotik routerboards can run a spectrum analysis, when used with their R52N mini-PCI card and newest RouterOS. Thinking about getting the Spectran HF-6060 V4.