Networking basics 101 - 2 routers question

[Puzzled]

Hi

This is probably a very basic question but I can't seem to find the answer on google.

My parents have a standard Sky hub (not q) which is connected to the phone line in a rubbish place and they insist it can't be moved (to be fair running a cable would be a nightmare).
I'm trying to improve their wireless range / speed and have offered them my Asus AC68U as I currently don't need it.

My plan was to run AV1200 powerline adaptors between the Sky hub and Asus but I need one device (printer) to remain connected to the hub via ethernet cable. Everything else will be plugged into the Asus.

If I disable the wireless / dhcp server on the Sky Hub and then use the Asus as the main connection point (set the gateway as the Sky Hub) will that still allow access to the printer?

Basically I don't want the powerline adaptors slowing down the whole network (planning to add a media server) which I'm guessing they would do if the Sky Hub was the DHCP server, or have I got that completely wrong?

 

[Zefan]

Your assumption that all traffic on your local network will pass through device with the DHCP server is incorrect, which thankfully makes things easier!

Devices on your network should only pass stuff to the gateway in the event that the destination address is not within your local net. I'd keep the dhcp server active on the sky hub, and use the Asus simply as a WAP. Switches remember what devices are directly connected, and will forward traffic to them. Because of this, all the devices apart from the printer should communicate through your Asus, only reaching over the powerline adapters for trivial things and when using the internet.

I don't think there's anything stopping you doing it the way you suggest it, but it seems a little backwards!

 

[Puzzled]

Ahhh that does make things a lot easier and it's not the first time I've made the wrong assumption

I always thought it was the router handing out the ips that handled the traffic and anything else was just passing it along.

That works well then as all the high speed devices will be plugged directly in to the Asus.

Another question, I've read about setting the sky hub to dmz mode. Does that mean it acts purely as a internet gateway? (Just curious)

 

[Zefan]

I'm not sure what dmz mode would mean for a home router like that, but really any DMZ will be the concern of the router's built in firewall. A device in a DMZ is exposed completely to the internet, as in, every port is open to requests from outside your network on any port. In contrast, by default, your firewall blocks traffic until a request goes out, then it remains open for a reply to that request on a specific port, so only genuine replies *should* get through. By putting a device in a DMZ all traffic will get forwarded through to it, solicited or unsolicited. My experience with it is limited, but I'd only use DMZ for temporary testing purposes, like trying to remote in to a machine on your network from outside on the internet.

Unless I'm misunderstanding your use of dmz, the only reason you should ever really use it permanently is if you're running some sort of server, and even then for a small/home network it's probably better to do port forwarding.

 

[Puzzled]

It's suggested as an alternative to extracting the sky fibre username / password to use with an openreach modem.

Basically in Access Point Mode, the Asus would act purely as a Wi-fi access point and all the router functions would be disabled.

If you want all the extra features, I would suggest you do the following:

Factory reset the Sky Hub.
Connect a cable from any LAN port of the Sky Hub to the WAN port of the Asus.
On the Sky Hub, set the IP address allocated to the Asus router as a reserved address so that it won't change.
Set the IP address of the Asus router as the DMZ.
Disable Wi-fi on the Sky Hub.
Connect all devices to/via the Asus router.

That way you can keep the advanced features of the Asus in use but in my case with the printer connected to the Sky Hub I don't think it would work.

 

[bremen1874]

That way you can keep the advanced features of the Asus in use but in my case with the printer connected to the Sky Hub I don't think it would work.

You're correct it wouldn't work. You'd be double NATing and the printer would be in a different subnet to the rest of the network.

Keep things simple and use the Asus as an access point and switch as you'd planned. The Asus should have an AP mode you can select in firmware which will allow it to be connected via its WAN port and leave all of the LAN ports free.

 

[neodude]

The other method of being able to use all the features of the ASUS is to use it in place of the SkyHub. I'm assuming that the SkyHub can't be converted into a Switch/AP in the same was as the ASUS can, so in that case you'd have to buy a new Switch and separate AP. Is the costlier but better option.

 

[Zefan]

The other method of being able to use all the features of the ASUS is to use it in place of the SkyHub. I'm assuming that the SkyHub can't be converted into a Switch/AP in the same was as the ASUS can, so in that case you'd have to buy a new Switch and separate AP. Is the costlier but better option.

I'd assumed the OP wasn't considering this approach due to having the RT-AC68U (no modem) and not the DSL-AC68U (built in ADSL/VDSL modem). If it is the DSL-AC68U and not the RT, then what you describe is the way I'd go about it.

 

[neodude]

I'd assumed the OP wasn't considering this approach due to having the RT-AC68U (no modem) and not the DSL-AC68U (built in ADSL/VDSL modem). If it is the DSL-AC68U and not the RT, then what you describe is the way I'd go about it.

Ah, never noticed that.

 

[Puzzled]

Changed it over today, powerline adaptor speed is a bit disappointing but will do the job. Wireless range is far better now and all seems stable.

Sky don't provide login details for third party modems / routers but you can sniff them out. I do have my old fibre openreach modem so might go down that route if the current setup causes any issues.

Thanks for all your help.