Cable signal "splitting"

[dave]

I want to move my Starbridge modem/router from my office to the living room where the TV is. There's only one female RJ45 cable jack there.

I'm told I can't put both my TV cable box and my router on the same RJ45 jack using a physical splitter device because "although you can physically connect two devices to the same jack, you cannot connect two devices to the internet on one jack."

True? Does it matter that the router is connecting to the Internet while the Cable Box is I think only "connecting" to the tv portion of the signal?

Thanks for any help.

[Deleted]

That technology is way over my head.

[clarencebunsen]

Interesting. Outside my house there is one cable coming from the utility pole. That runs to a Time Warner enclosure. Exiting the enclosure are 4 cables running to various parts of my house. What could be in the enclosure other than a splitter? The enclosure has no power so I don't see how it can include a signal amplifier or any active device.

I presume there has to be a splitter somewhere to route the cable to your study and living room. If that splitter were replaced with a barrel connector and the splitter moved to the living room wouldn't that be an equivalent circuit?

[Clipper]

Our charter service comes in on one coaxial cable to a box on the bedroom wall. That box DOES plug into the wall and has 4 coaxial outlets and several flashing lights like an oversize modem. We have tv, phone, and internet all splitting at that device and routed through the crawl space to the individual rooms and devices. I DO note that all 3 tv's are split off of one line where it leaves that box, the telephone on a separate line and internet on a single line to my desk area.

I have no clue as to the technical aspects of all of that but thought I would offer up the info anyway, lol.

[dave]

It's been a long time. I do remember with data networks we had splitters versus switches. Routers allowed one to hook to multiple networks, switches allowed multiple PC's to hook to one network. Splitters are for devices that don't hold a session with each other or don't send addressed packets to each other, I think.

Clipper, TV and phone is different. You can use splitters to Y off as many TVs as you want until you pull down the signal power. But with network devices like a PC it's more complicated. If you tried to Y or split off of one PC connection of your router I believe it would not work. That's the same problem I would experience if I tried to Y or split coming off the cable wall jack. TV's and phones are fine, but not addressed devices, I think.

CB, I think the raw signal on the cable is indeed split up via just physical splitters to get it around the house. Same here. But if you were to go to one of the boxes and try to split off two PCs, or any network device, I think you'd have the same problem I'm having. Splitting off two phone or TV's or a mix is OK, but not network devices.

I think that's all true. Maybe Ralph can help clarify for us.

[Ralph]

I'm really not positive on this Dave, but you should be able to split it outside the box and have one run to the TV and one to the modem with no adverse effects.  When we had our cable here through Adelphia I had six TV's going and in my office upstairs had the cable split just inside the wall with one run to the TV and one to the modem, worked fine for me.
At that time they were having enough problems of their own and it was out almost as much as it was in, but when in it was fine.  There are times when the "cable" was out but I still had access to the internet and visa versa. 

Give it a try, nothing ventured nothing gained and all that!

[clarencebunsen]

That raises some interesting points Ralph. Like you I have cables all over the house; TV, telephone, an unused ethernet system. It spreads over two floors plus the basement & attic.I've been trying to troubleshoot a problem that Time Warner couldn't fix. We recently added a cable box to our bedroom so Barb could watch Law & Order before she goes to sleep. Unfortunately not all the channels work and USA is one of the no shows. Now I have to go up into the attic and duck walk around on the rafters tracing cables & splitters. I'm getting too old for that sort of stuff.

[dave]

CB, that has a familiar ring .... splitting a cable signal and getting only half the channels. I think that happened to me some years ago but I was never sure if it was the splitting or the TV the signal went to where channels were missing.

Ralph, yes, that's what I'm thinking, if at one jack one device is network addressable, such as a router, and the other entity is a TV, should be no problem. But maybe something on the new TV as some addressable aspect to it.

In any event you're right. I should just try it. But I wish I understood it.

Also, I found some references on the Internet where (speaking of, e.g., splitting off a cable jack to Two PC's), there is need for a switch. And supposedly switches are available cheap on eBay. I'll take a look at them for a backup plan.

[dave]

I forgot to mention that it's a matter of "ports." You need two ports for two network addressable units. To physically divide or split the signal is not enough. That's why a switch is needed, I think, to provide the two ports. The network
needs a port for each addressable device. doesn't care about phone or straight TV's. But routers and PC's and such each need a port.

[clarencebunsen]

Apr 3, 2014 11:26:22 GMT -5 dave said:

I forgot to mention that it's a matter of "ports." You need two ports for two network addressable units. To physically divide or split the signal is not enough. That's why a switch is needed, I think, to provide the two ports. The network
needs a port for each addressable device. doesn't care about phone or straight TV's. But routers and PC's and such each need a port.

You're right, a box sending and receiving needs to have an address. On the back of my modem are several outlets: 2 phone connections, a usb port, an ethernet connection which goes to the router and a TV cable jack which goes to the attic. The last is the one which I believe goes to the cable box in the bedroom. However I do not know if that is a port.

New plan: I will walk the box & TV to a point where the TW tech told me I had sufficient signal to run a box. That comes directly from the TW enclosure outside the house. I don't know if he measured just signal strength or two way capacity. If it works there I'll route a cable from that point through the attic to wherever Barb wants her cable box.

Back up plan: If I can't get the box to work I'll return it and buy a Chromecast gadget for her TV and a subscription to Netflix. Chromecast costs $35. Cable box is $5 or $6 per month. Netflix is $8 per month. Compare that to the emotional cost if I damage myself in the attic after I've been to not to go up there and with play cables while I home alone.

[Ralph]

Dave, if you are coming out of a router or a modem/router and don't have enough ports (or only one) you can run a "switch" to supply more ports to your "hard wired" setup.

I am running a Linksys/Cisco Model E4200 wireless router with only four ports (out of a Verizon DSL single port wired modem) and have them sucked up with two PC's in the office and one downstairs as well as our World Book Network HD here in the office.
Once I added the two camera systems I needed more ports.

I went ahead and added a Netgear 8 port Gigabit switch and solved that problem right quick. No lags or problems with it and it's been about a year and a half since I installed it.

I went with that router as it was "the best" that could be had at the time and with the Netgear switch as I had used one of their routers before and they are just plain built like tanks!

The closer you get the switch to the router or modem the better off you are I am told and have to assume that at some point you will lose a bit of signal over distance. But in this old house I have (as CB does) countless feet/yards (perhaps miles) of cable and network cable all over the place and have no loss that I can really speak of. My antenna system for the TVs suffers a bit, but I have an amplifier in the system line to make up for it.

If you goal is to run off a single port modem without a router a switch is the way to go, but  you won't be able to "network" the PC's together so they can "see" each other without a router.

I included the links below so you can see what I am running here, it is not where I purchased them from.

Router: store.linksys.com/Routers/Linksys-E4200-MaximumPerformance-Wirelessn-router_stcVVproductId122703236VVcatId550467VVviewprod.htm

Switch: www.newegg.com/Product/Product.aspx?Item=N82E16833122111

[dave]

Thanks, Ralph. If I can get to it this weekend, I'll try a few arrangments. Your last post filled me in with details I need to begin to understand this thing, although I need to find more info to truly understand it. Thanks for the help.

[Ralph]

You're welcome!  You need anything just drop me a PM if I'm not around.

[dave]

Thanks, Ralph. As always, I appreciate your help.
Dave