Networking – How to setup Home Networking DMZ Using Two Routers

dmzlannetworkingrouterwan

I decided to get a better router than using my ISP supplied modem/router.  Thus I am not interested in using my new router as access point nor bridge mode.   I prefer having two internet accessible routers. 🙂

Hardware:-
1)  Main ISP supplied Modem router:  ZTE ZHXN H108N V2.5 IP address is 192.168.254.254 (ISP supplied modem router)

2)  Secondary router: TP Link AC2300 IP address is 192.168.0.1 (router).

ISP broadband connection is through PPPoE.

Planned set up:

ISP Modem/Router (ZTE ZHXN H108N) LAN port —->connect through DZM mode —>2nd router (TP-Link AC2300) WAN port


Router 1 (Main ISP supplied Modem router ZTE)

WAN IP Address: xx.xx.1xx.xxx (default by ISP)

LAN Setup
LAN IP Address:  192.168.254.254 (default by ISP)
Subnet Mask: 255.255.255.0 (default by ISP)
DHCP:  ON
DHCP Range:192.168.254.100 to 192.168.254.200 (default by ISP)

WIFI: OFF

NAT: ON (Guessing here.  Not sure if it will cause double NAT issues.  Please comment.)

UPnP:  ON
WAN Connection: (what to put?)
Advertisement Period (in minutes): not sure what is this?
Advertisement Time to Live (in hoops):  not sure what is this?

DMZ Setup : ON
WAN Connection:  (what to put?)
DMZ Host IP Address: 192.168.0.10 (router 2 IP Address is that correct?)
MAC : ON

Port Forwarding:  Have to setup or not?


Router 2 (TP-Link AC2300)

WAN IP Address: 192.168.254.254 (Guessing here to use Router 1 IP address)
Gateway: 192.168.254.254
Primary DNS Server:  192.168.254.254

Static IP on WAN Port: 192.168.0.10 (correct or not?  Does it have to be the same as the LAN IP Address?)

LAN Setup
LAN IP Address:  192.168.0.10 (is this correct?)
Subnet Mask: 255.255.255.0
DHCP:  ON
DHCP Range:192.168.0.100 to 192.168.0.200

WIFI: ON

NAT: ON (Guessing here.  Not sure if it will cause double NAT issues.  Please comment.)

UPnP: ON

FIREWALL:  IPv4 IPv6: ON

Internet Connection:  through Static IP

====================================

Question: 
1) Do I enable the DHCP on BOTH the main modem/router (ie the ZTE ZHXN H108N) and secondary router (TP Link AC2300)? Will it conflict each other?  What range should I put on both?  Does it have to be very different IP address range?

2) Will connecting two routers caused double NAT? Will that even be an issue?

3)  How about Voip? Will it be effected?

4) How about the UPnP? Do i enable it on both or none?

5) What internet connection type do I choose on the secondary router TP Link AC2300 since it offered 5 types (Dynamic IP, Static IP, PPPoE, L2TP and PPTP)?

7) Should I turn off the wireless radio on the ISP modem/router (ZTE)?

8)  Is there two static IPs in a router?  One for WAN and one for LAN?  If so, how do I set it up for both router 1 (ISP supplied modem router ZTE) and router 2 (TP Link)

Thanks in advance.

Best Answer

8) Is there two static IPs in a router? One for WAN and one for LAN?

Yes – a router, by definition, connects multiple networks and has an address from each network that it's on. So the WAN interface has its own address and the LAN interface has its own. (They might not necessarily be static though – e.g. the "WAN" address is usually dynamically obtained via DHCP.)

So with that in mind,

  • WAN IP Address: 192.168.254.254 (Guessing here to use Router 1 IP address) Gateway: 192.168.254.254 Primary DNS Server: 192.168.254.254

the "Gateway" field is correct, but the "WAN IP address" field is not: it defines the 2nd router's own IP address. So if the upstream (1st router)'s LAN interface is 192.168.254.254/24, then the TP-Link (2nd router)'s WAN interface could be 192.168.254.7/24 or something.

(A bridge however (e.g. Ethernet switches, Wi-Fi access points aka extenders, Powerline adapters) links a single network together, so usually has only one IP address – and that address is only used for managing the bridge, not for actually forwarding packets.)


So at first you need to decide whether you want the ISP device to stay in router mode (having two LAN subnets in total) or whether you want it to be in bridge mode. I would recommend the latter: now that you have bought a better router, you don't need the ISP device to act as a router anymore.


1) Do I enable the DHCP on BOTH the main modem/router (ie the ZTE ZHXN H108N) and secondary router (TP Link AC2300)? Will it conflict each other? What range should I put on both? Does it have to be very different IP address range?

Your TP-Link device is a router, and you specifically stated that you want it to be a router. So it has to have different networks on its WAN and LAN sides.

For example, if the ISP router's LAN (which is also the TP-Link's WAN) uses 192.168.1.0/24, then the TP-Link's LAN could be 192.168.2.0/24.

The two networks can both use DHCP without any conflict, because there is a router separating them.

2) Will connecting two routers caused double NAT? Will that even be an issue?

If the ISP device remains in router mode, yes, generally this will result in double NAT. It might cause annoyances such as making port-forwarding twice as difficult.

If the ISP device cannot act as a bridge, then it should at least have the TP-Link configured as its "DMZ" host.

3) How about Voip? Will it be effected?

It depends on the protocol used, and on the outcome of question #2. With double NAT, SIP might be affected more than other protocols.

4) How about the UPnP? Do i enable it on both or none?

It's a link-local (same-subnet) protocol. Devices connected to the TP-Link router will only talk UPnP IGD to the TP-Link.

The TP-Link router itself won't talk UPnP IGD to its upstream router. (It's not technically impossible, just never done because such routers expect to be connected to an ISP, not to another router, and ISPs do not talk UPnP IGD at all.)

5) What internet connection type do I choose on the secondary router TP Link AC2300 since it offered 5 types (Dynamic IP, Static IP, PPPoE, L2TP and PPTP)?

If the ISP device is in bridge mode, the TP-Link router should inherit its settings exactly, so choose whatever the ISP wants.

If the ISP device is in router mode, it certainly won't be offering something as complex as PPTP or PPPoE to its LAN devices (i.e. to the TP-Link) – just regular IP. Whether you want the TP-Link to have a static or DHCP (dynamic) address is up to you. Dynamic would be simpler to deal with.

7) Should I turn off the wireless radio on the ISP modem/router (ZTE)?

If it's in bridge mode, yes.

If it's in router mode, probably also yes, because devices connecting to it would bypass the TP-Link.

At minimum, if both routers end up providing Wi-Fi, they must have different network names (SSIDs) because they provide access to different subnets. Otherwise devices roaming between them would get very confused.

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