Subscriber Discussion

DVI Encoder And Decoder Over Ethernet

U
Undisclosed
May 29, 2015

I am looking for some recommendations to solve the following issue:

I want to be able to take a DVI output out of a graphics card on a computer and ship the video to a monitor on the same corporate LAN but physically several miles away. I do not want to use a web client or even a computer on the remote end. I have a user group that will simply ask the guards to pull up cameras looking at views that they are interested in on their VMS client workstation - they will then see the same view on their remote monitor. That way there is no training or knowledge of what cameras to view needed. I am looking for a device that can encode on one end and then another that can decode on the other end.

U
Undisclosed #2
May 29, 2015

You're unlikely to find this device directly. I've never once seen anything like it.

DVI has a max bandwidth of 1.65Gbps. So it's going to exceed any standard Ethernet link, and almost certainly any sort of WAN traversal.

That means you need to do a lossy compression of the source signal in order to transmit it to the remote end. Keep in mind that for many kinds of remote viewing things (Webex, VNC, RDP, etc.) this lossy compression works out OK, but it's very video-detail unfriendly (for hopefully obvious reasons).

Or, to put it another way, you're going to need a sort-of computer on either end. Might as well look at it from that perspective.

I think there are some things you could do with Teamviewer-ish solutions that would give you almost the "hands-off" scenario on the remote side that you are looking for.

U
Undisclosed #3
May 29, 2015

How about this

1.DVI to HDMI

2.HDMI to HDMI Over Gigabit IP Network Range Extender

then you have HDMI output to Monitor ( or DVI )

U
Undisclosed #2
May 29, 2015

There are several units that claim to do "Ethernet" range extension, but everyone I've seen has poor reviews and/or essentially assumes it has a dedicated network, meaning they will use ALL available bandwidth.

None of them handle a scenario of routed packets (which I'm making an assumption here that a modern corporate LAN spanning long distances and multiple buildings is indeed routed and not a giant switched single-broadcast-domain LAN).

TC
Trisha (Chris' wife) Dearing
May 29, 2015
IPVMU Certified

Take a look at these guys, they are quite popular with the home automation crowd.

If you like standards, there's HDBase-T.

U
Undisclosed #2
May 29, 2015

From what I can tell, both of those boxes use *twisted pair*, not *Ethernet* (though one of them can provide an Ethernet link along with the HDMI extension).

Neither would work on a "corporate LAN" as OP specified. The first option has a cable length of 1 mile max, which is great except that the remote site is "several miles away" (and almost certainly does not have a dedicated twisted pair cable plant between them).

TC
Trisha (Chris' wife) Dearing
May 29, 2015
IPVMU Certified

From what I can tell, both of those boxes use *twisted pair*, not *Ethernet* (though one of them can provide an Ethernet link along with the HDMI extension).

Neither would work on a "corporate LAN" as OP specified.

Disagree. Although I have seen units like you describe, these ones from JAP are IP over Gigabit *Ethernet*. They can run over various third party Layer 2 or Layer 3 switches from Cisco and Dell.

They can co-exist with 'regular' ethernet traffic in the same topology. Two caveats are that you need to create a VLAN for the video, something you would likely do in any case, and enable multicasting, something you would likely NOT do normally.

Bandwidth can be scaled by using SFP 10 gig modules in the switch if desired. I agree its hard to find all the information in one place, but this manual is pretty good for the most part. I didn't see the part about the one-mile limitation, where did you find it?

I do think that because of bandwidth concerns the Antrica device is the better route, but I do believe on a connectivity/infrastructure level this solution is not just twisted pair.

U
Undisclosed #2
May 29, 2015

I didn't see the part about the one-mile limitation, where did you find it?

It's one of the bullet points in the feature list on the page you linked to. It also led me to believe they were misuing the term "Ethernet", since Ethernet distance limitations are based on propagation timings not on transmit/receive strength. I see a lot of A/V products munge defiitions like that, calling anything running over twisted pair "Ethernet" as a generic term.

From looking at the JAP site (the link from the page you linked to didn't work and I didn't have time to google around for it) it *does* appear that these do use standard Ethernet (and presumably IP, though technically they could use IPX for all it matters) comms.

Bandwidth can be scaled by using SFP 10 gig modules in the switch if desired.

Assuming that OP has a modular switch *and* the cable plant over that "several miles away" span can handle it as well. Personally I doubt that BOTH of those are true, but it *is* possible.

I think that those products are pretty cool and might work if it was a pure LAN, ideally with dedicated switches, but I'd be *very* skeptical that they would work acceptably over a corporate LAN that includes a distant site.

TC
Trisha (Chris' wife) Dearing
May 29, 2015
IPVMU Certified

To be clear, you said

The first option has a cable length of 1 mile max

But the bullet point you refer to stated the opposite:

Handles cable runs over a mile

Which needs clarification for sure. I found this forum exchange between an engineer from Justaddpower and a user.

I'd like to share a couple things when it comes to using Just Add Power over long distance.

1) The official "supported" distance for CAT5E is 330ft (100M) between network points. If you put an extra baby switch in the middle (a dirt cheap 4 port GB switch for under $30 will work), you can easily go 660ft. Add another baby switch, and you are up to 990ft from the main switch to the display.

2) Going through fiber to expand the network is also supported. I'm personally aware of installations over fiber that have exceeded 6 miles from the HDMI source to the target HDMI display using our devices.

3) The longest distance install I've encountered was over 20 miles using some pretty sophisticated network extenders.

4) We have had dealers call to report that they were able to use a single CAT5e cable over 500ft long with no problem, but that's just crazy talk.

5) If you can build a working network with sufficient bandwidth, there is really no distance limitation using our products.

Which, if they really are using IP and Ethernet as they claim, is what you would expect.

I'd be *very* skeptical that they would work acceptably over a corporate LAN that includes a distant site.

I couldn't say without knowing the details of the LAN, that's why I said only for him to 'take a look'. Which seemed helpful since the prevailing wisdom at the time was

You're unlikely to find this device directly

Sorry about the link, if it just hung for a while it's because it a big pdf.

TC
Trisha (Chris' wife) Dearing
May 29, 2015
IPVMU Certified

Also, if you don't need 100% lossless compression, and why would you really since your are your source is already compressed, or if bandwidth is a concern, you could use two of these H.264 and ONVIF compliant encoder/decoders from Antrica.

U
Undisclosed #2
May 29, 2015

Nice find, I hadn't seen an HDMI/DVI to IP encoder yet that I recall. The issue then would likely be bandwidth between the two sites using something like this as you mentioned.

U
Undisclosed
May 29, 2015

I believe the Antrica units will work over our corporate LAN. They go over a scenerio much like the one I described in this summary:

http://www.antrica.com/applications/applications-pc-images-over-ip/

CW
Craig Wilson
May 29, 2015

What VMS are you using? I know Exacq Enterprise has the ability to push a view to another viewer. We have done multiple installations like this where we have security guards push video to certain managers, makes this very easy as you just have a PC without a keyboard or mouse, when they push video it just shows up. I wouldn't screw around with extenders or try to mess around with team viewerish solutions. Also I think Onssi and possibly Milestone has the video wall feature as well where you set it up as a video wall and remote clients can push video views to it. I would walk away from encoders/decoders, and i would avoid using any sort of IP extenders, your going to make this a service nightmare.

(3)
TC
Trisha (Chris' wife) Dearing
May 29, 2015
IPVMU Certified

Also, to be considered is the all-in-one IP PVM* ONVIF public view monitor.

*No relation

U
Undisclosed #3
May 29, 2015

Also,

Window HDMI Stick use as Client

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