Wi-Fi & connectivity

[atc98092]

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@JKasten wrote:

Re Router and Switch functionality:  Not being familiar with the purpose of ethernet Switches (being neither Hub nor Router) I was thinking one might serve as a means to allow multiple devices to connect separately to the Internet (via the Modem).  Apparently, this is not the case, so I'm left puzzled about the actual functional purpose and capability of a Switch.  And, if the Router is responsible for assigning local port/device addresses, then how can a Switch "expand" the ports/devices - without running into the same individual addressing problem as when the Switch connected directly to the Modem.  Is the Router able to "manage" a cascaded Switch, or...??? (Not quite "getting" this aspect).   

About the expansion port-count, the Routers typically have four ethernet ports, so connecting a four-port Switch to the Router would provide a total of six available ethernet ports, correct?  (One port on the Router and one port on the Switch are required for the connection between them)?

Re Firewall:  Yikes!  I had assumed the Cable Modem provides a firewall - and/or there is a "soft" firewall in the laptop's security suite.  If the Modem doesn't provide this, then I'm even more "exposed" than I'd imagined!

Thanks for all the great info!

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Switches do not provide any routing, firewall or DHCP functionality. They provide additional Ethernet ports, period. Some higher level switches do have more advanced features, but those are not typically used in a home environment. Yes, you can cascade switches to provide additional ports. I have a 16 port switch in my garage near the modem and router that feeds cabling throughout my house. I have additional switches in my den and family room to provide additional ports in those areas, along with wireless access points that increase my WiFi range. All DHCP functionality is handled by the single router in the garage that provides my firewall to the Internet.

Under its default configuration, the cable modem does provide a firewall between your home network and the cable company's network which in turn connects to the Internet. It provides the DHCP service that offers IP addresses to connected devices, and the Network Address Translation (NAT) functionality that hides your local network from the outside. But as I mentioned, some cable companies restrict your access to some of the settings in the modem, so you don't have full control of your network security. That's why I changed the Xfinity modem to bridge mode (which doesn't provide any firewall protection or network services) and instead use my own router for that function. 

[JKasten]

makalguy:

The Switch that I obtained for my first try is a Netgear GS308 (unmanaged 8-port Switch).  My (very) limited understanding of the function of such Switches is that the Switch has enough "smarts" to route traffic between ports that are "requesting" the traffic.  Consequently, I thought that it might serve as a pseudo-Router allowing the several ethernet devices to independently access the Internet - and thus avoid the expense of getting a Router.  Also, the Switch has enough ethernet ports for all the branches that I need, where the typical 4-ethernet-port Router comes up short on ports.

Now, for the most part, I won't need all six ethernet devices connected to the Internet at any given time (typically only one or the other group of two or three at any given time - upstairs and downstairs).  So, perhaps some sort of "manual" ethernet selector Switch(es) would suffice - although they would be a bit of a pain to change manually as frequently as needed.

Thanks for the heads-up.

[JKasten]

atc98092:

Thanks for your replies.

I strongly suspect that the Spectrum Modem is using the same scheme as your Comcast, as it clearly does not allow more than one device to be connected at a time - and needs to be re-started in order to "assign"/recognize each newly attached device.

I also suspect that Spectrum is "pushing" Wi-Fi over ethernet connectivity, seeing they make it quite difficult to "avoid" Wi-Fi.

Like you said about your Comcast Modem, I have virtually no access to the settings of the Spectrum Modem, leaving me unable to do things like bridging.  Consequently, I'm also considering going with my own Cable Modem - but am reluctant because I don't really want the hassles of managing and troubleshooting my own equipment (being not all that knowledgeable about it).  But it's certainly in the mix of considerations.

Thanks.

[atc98092]

There's two pieces of hardware that allow connecting multiple Ethernet devices: switch and hub. The main difference is the hub simply broadcasts the Ethernet packets to every port, while the switch is smart enough to read the packet header and only send it to the port connected to that device. That means a switch can reduce traffic on a specific port by not clogging it with unwanted traffic.

But the switch cannot perform the functions of routing that a router can do. The switch cannot assign an IP address to a connected device, it can only relay that request to the DHCP server on the network (usually the router).

There really is no way to "manually" switch the Ethernet ports, other than actually disconnecting the cable from the switch. There's no issue leaving devices not currently in use connected to the network switch, UNLESS your cable modem doesn't provide enough IP addresses to the connected devices. I mentioned previously that in the past some cable modems would only provide one or two IP addresses and refuse any additional address requests. It almost sounds like yours is doing that, and the only solution is to use your own router between the modem and your network. A personal router can assign 253 IP addresses under default settings. That should be more than sufficient for almost any home network. I have a well connected home, and there's currently a total of 50 connected devices. 

[atc98092]

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@JKasten wrote:

atc98092:

Thanks for your replies.

I strongly suspect that the Spectrum Modem is using the same scheme as your Comcast, as it clearly does not allow more than one device to be connected at a time - and needs to be re-started in order to "assign"/recognize each newly attached device.

I also suspect that Spectrum is "pushing" Wi-Fi over ethernet connectivity, seeing they make it quite difficult to "avoid" Wi-Fi.

Like you said about your Comcast Modem, I have virtually no access to the settings of the Spectrum Modem, leaving me unable to do things like bridging.  Consequently, I'm also considering going with my own Cable Modem - but am reluctant because I don't really want the hassles of managing and troubleshooting my own equipment (being not all that knowledgeable about it).  But it's certainly in the mix of considerations.

Thanks.

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Yeah, it really sounds like they have you restricted to a single IP address. I can't speak to Spectrum, but Comcast did allow me to switch the modem to bridge mode via the app or web interface. I know everyone pushes for WiFi, but there's still plenty of places I prefer a wired connection.

I can understand your hesitancy to manage your own network. I have over 20 years of computer and networking experience, and I still occasionally run into issues. Fortunately, most routers will work just fine the way they come out of the box, so it's not necessary to make changes to get it working. There's certainly far more you can do once you can control everything, but don't think it's a necessity to just get things up and running. Purchasing and installing your own cable modem will require much of the same configuration, and perhaps more depending on how Spectrum requires the account login with the modem. 

[JKasten]

atc98092:

Regarding your second reply, the functionalities of Switches are becoming clearer - although I'm still a bit puzzled about how the Router can "oversee" devices that are connected via a cascaded Switch.  I also wonder whether Switches can be cascaded off of other Switches and still work properly.  (This would help with physical cable routing, because I could run just one cable upstairs, and feed a Switch there - instead of running three separate cables from a Router/Switch combo downstairs.  Also, it would help the cabling aspect if I could feed a second Switch also from the Router to feed the two Rokus planned for downstairs - which are physically separated from the Laptop feed.  Putting Switches near the grouped devices would reduce the number of long-run separate cables - although it might negatively affect performance).

If a Router's firewall is as effective and controllable as an owned Modem's firewall, then it may be more practical to see if my Modem can be bridged as you mentioned (versus getting an owned Modem).

Thanks!  

[atc98092]

Yes, Ethernet switches can be cascaded without an issue. The router does not need to know the exact port of every connected device, it only needs to know which of its own ports are used to reach it. Once the packet is sent out of that port, it reaches the second switch, which again knows which port each device is connected to. If the device in question is connected to the second switch, it sends the packet to that port. If it's a wireless device that is connected to an access point connected to that switch, the packet is sent to the port the AP is connected to, and the AP will then broadcast it via WiFi. If the packet comes into the second switch, and the device is connected downstream to a third switch, the packet is sent on to that switch. They really are quite intelligent, even though they are referred to as "dumb" or "unmanaged" switches. A Smart/Managed switch is actually assigned its own IP address and can perform many more routing functions. But again, those are typically used in enterprise networks, and not normally used at home. 

Your scenario of running a single cable to a location then add a switch at that end is exactly what I'm doing in the room I'm in right now as my home office. There's an eight port switch blinking away at me, with my home and work computer connected via Ethernet, as well as a Smart TV in the room. I have an access point sitting behind my main monitor, so it's connected to the switch as well. There's five active connections on that switch, plus any wireless devices that are connected to the access point. That's four devices plus the cable that runs to the main 16 port switch in my garage (right below me).

[JKasten]

atc98092:

OK, you confirmed my (limited) understanding of the function of Hubs and Switches - so I guess I was on the right track.  (Speaking of Hubs, I found an ancient - but apparently unused - 4-port 10base-T Hub in my stash of ethernet parts, while I was rummaging for some ethernet cables.  I wonder if that old Hub is good for anything?)

I did not really think that a Switch would serve my current Roku need, but an "IT Guy" claimed that it was all I'd need, so I figured it was worth a try - as a lower-cost "solution".  Thought he said that it was how he had his own home Rokus set up. (?)  (Anyway, I thought that a Switch might be needed even if it turned out that I really needed a Router - which has proven true, so no "wasted money" there).

I currently anticipate a maximum of six ethernet devices will need to access the Internet - so it should be a minimal network... but will need "expansion" beyond the typical Router.

[atc98092]

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@JKasten wrote:

(Speaking of Hubs, I found an ancient - but apparently unused - 4-port 10base-T Hub in my stash of ethernet parts, while I was rummaging for some ethernet cables.  I wonder if that old Hub is good for anything?)

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Yeah, it should work as a doorstop. 🤣 In reality, it's far too slow for any practical use, and being a hub instead of a switch would make it even slower since there would be so many packet collisions. Literally everything online now is capable of 15 Mbps of faster, so a hub that would have less than 9 Mbps real world throughput would really be a bottleneck. 

[JKasten]

atc98092:

OK, thanks... now the routing through cascaded switches makes sense to me.

I'm wondering what effect the cascading has on performance, though.  I don't know what the Rokus actually need performance-wise but my incoming is sort of "shoestring", so I don't want to degrade things much.

By the way, in an ethernet/Wi-Fi router, are the ethernet ports entirely separate functionally from the Wi-Fi, or is it a situation where you "lose" a Wi-Fi "port" for each ethernet port that is connected?