[RndTbl] wireless basics

John Lange john at johnlange.ca
Sun Jan 22 08:32:49 CST 2012


On Sat, Jan 21, 2012 at 9:44 PM, Sean Cody <sean at tinfoilhat.ca> wrote:
> On 2012-01-21, at 7:22 PM, Dan Martin wrote:
>> ... but you don't need a MAC address to route a frame to someone else?

If you put your wireless into "bridge" mode you're basically just
disabling the router functions so it acts only as a switch. As a
switch it will transparently "echo" (bridge) traffic from the wireless
to the LAN and vice versa.

Most home routers are actually (at least) 3 devices in one, router,
switch and wireless access point all managed from a single web
interface, but inside they are still 3 separate network devices.

Your confusion comes from the fact that even in bridge mode it still
has a NIC with a mac and an IP. This is just so it can have an IP
address and be managed remotely but as far as the network is concerned
it's just another end-point, not a "router".

If you put your router back into "router" mode, it will still bridge
traffic from the wireless to the LAN and therefore it will still not
show up on a traceroute fromLAN to wireless (or LAN-to-LAN). However,
it will show up on a traceroute from the LAN to the WAN.

Don't let the wireless confuse you. Just think of wireless as a
replacement for wires. Instead of two RJ45 connectors, you have two
radios. They are a bit more complicated to connect (SSID etc), but
once the link between the two radios is established, the wireless
"goes away". Just like with a physical network cable, once you plug it
in and the "link" light comes on, you just forget about it.

John


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