Feeling Smug..

[Bryanpoprobson]

Have a wi fi dead spot in my bedroom. So I asked my provider (BT) if I could used one of their old hubs (hub 4) as a slave router from my main router (hub 5). They told me categorically that it wasn't possible! Twenty minutes of giving it some thought and five minutes of configuration work and I have a good wi fi throughout the house, using an old router I was going to throw away.

Technical support lol, I made a point of calling them back with my solution method..

Feeling smug, so I thought I'd share this..

[Echnaton]

Most routers are capable of serving as an access point. But it isn't always obvious how to do it.  Good for you in figuring all this out.  Getting stable WiFi through my home and yard took some time but was worth the work and expense.

[BazBear]

It figures they would tell you that. Most old wireless routers, at least as far back as the original Linksys WRT-54, can even be turned into wireless repeaters, if you flash them with 3rd party replacement firmware such as DD-WRT. I have a wireless repeater set up in my house to deal with such a dead area.

[Echnaton]

When I finally did my home network right, it took four access points and a switch.  Three APs inside and one in the garage, and running Ethernet to each one and also to two TV's.  Thankfully I did it in the winter.  It was really needed once we cut off Comcast cable TV and no one complains anymore about Netflix or Amazon Prime stuttering. 

[ka9q]

Not sure what you mean by "slave router", but it's always been possible to configure several access points with the same SSID, configure them for bridge mode (or use the downstream ports) and connect them all to a switch, and your laptop will pick whichever one is strongest.

We can cover our house pretty well with just two access points, but they're ceiling mounted. Power comes through the Ethernet (POE).

[Luther]

It figures they would tell you that. Most old wireless routers, at least as far back as the original Linksys WRT-54, can even be turned into wireless repeaters, if you flash them with 3rd party replacement firmware such as DD-WRT. I have a wireless repeater set up in my house to deal with such a dead area.

I've done this kind of flashing.  I was really nervous about it, figuring I might destroy the decide, but it worked just fine.

[Bryanpoprobson]

The trick with the BT Home hub was to turn off the DHPC option on the repeater hub. I knew the repeater had to have static IP router leaving the main as Dynamic, but when I tried this before it didn't work. The DHPC uses dynamic IP addressing as a side channel for public hotspotting and it was this that stopped it working.

[Luther]

Arg, it seems one can't edit posts at this board, leaving my typo for all to see for all eternity 

[Allan F]

You can edit for a limited time, after you post. Then the post is locked. This is because a hoax believer (what was his name?) in a meltdown started to delete his posts, not wanting his strange ideas to be documented for eternity.

[onebigmonkey]

Our IT support at work is outsourced, but I have the problem of having to provide local IT support for some bespoke software we use which gets transmuted into "all other IT related issues".

I am particularly fond of solving things our IT says "can't be done", up to and including getting administrator access to the registry to edit keys that have been broken (so easy it's laughable).

[ka9q]

The trick with the BT Home hub was to turn off the DHPC option on the repeater hub.

I think you mean DHCP, Dynamic Host Configuration Protocol. A DHCP server hands out IP addresses on a particular subnet (typically a LAN or group of bridged LANs). You can have more than one DHCP server on the same subnet but it's usually a good idea to coordinate them. And it's usually unnecessary.

DHCP servers hand out more than just IP addresses. They also tell you the address of the local default router to the outside world, and they usually also act as DNS (domain name system) resolvers. You don't want to hand out conflicting information here.

A typical home or small office LAN needs only one subnet and one DHCP server, and you typically (but don't have to) run the DHCP server on the same physical box that provides NAT (network address translation) and routing to the outside world.

Your commodity wifi base station/DHCP server/router/NAT box has a bunch of Ethernet ports connected to an Ethernet switch, which means they're on the same subnet. The router/NAT/DHCP/DNS functions usually run on an embedded Linux system that sits between that switch and a separate Ethernet port for an upstream connection. Sometimes a built-in cable or DSL modem takes the place of the upstream port.

So if you want to add additional base stations to your existing network, you can use WiFi/router/NAT boxes as long as you disable the unneeded functions (routing and DHCP) and connect one of the LAN ports to your main router's switch. Then they'll all be on one common logical subnet and be able to see each other just as though they were all using the same base station or Ethernet switch.

Typically just disabling the DHCP server is enough because then no one would even have reason to know that the routing and DNS resolver functions are there, so they won't cause any harm.

 

[Bryanpoprobson]

Yeh.... That mouthful is basically what I did..  LOL! Wouldn't work off the WAN port had to connect via one of the Ethernets..

[ka9q]

Right, because traffic between the WAN and LAN ports has to go through the (usually) Linux system inside the box, which is usually configured as a router with NAT. That system, as well as the WiFi device, have internal ports on the Ethernet switch.

Packets between the LAN ports (including those for the router and WiFi) only go through the switch, which has low-level firmware that passes Ethernet packets as-is or drops them, depending on whether they need to go to a particular port. It keeps a table of Ethernet source addresses and which ports they come from. When a packet arrives, the destination address is looked up in the table and the packet sent to the port where that address is known to be; it is not sent to any other port.

Multicast and broadcast addresses never appear in source fields, and in any event are treated by the switch differently; multicast packets are sent out every port except the one they came in on so everybody gets them. Some switches "snoop" on IP-level IGMP traffic that says which computers are members of a particular multicast group so the switch can suppress traffic to computers that are not interested, but this function is not in most cheap commodity switches.

[Bryanpoprobson]

The only irritating thing is that the status light that should be blue, glows orange and the broadband light is flashing red... But hey it works..

[BazBear]

It figures they would tell you that. Most old wireless routers, at least as far back as the original Linksys WRT-54, can even be turned into wireless repeaters, if you flash them with 3rd party replacement firmware such as DD-WRT. I have a wireless repeater set up in my house to deal with such a dead area.

I've done this kind of flashing.  I was really nervous about it, figuring I might destroy the decide, but it worked just fine.

It's pretty safe as long as you fully follow the flashing instructions. I've probably done it to 10 or 15 routers of various makes and models, and I've yet to "brick" one, though I've had a couple that acted flaky after flashing, and I had to flash them again.