Network infrastructure setup help

[Chavo]

From OP:

* I want to install the networking hub in my utility room inside of cabinets.  This would put the wireless signal coming from a non-central part of the house, AND it would be close to electronics that could disrupt it, specifically, the washer/dryer.

I figured there wasn't a real difference between an Access Point and a router with NAT/DHCP turned off (again, I've never checked because I've never had a use for it), but it does leave the open question (that I'm sure a good answer exists for) of how the AP manages the DHCP router <-> AP <-> Wireless Client connections.

[MyndFyre]

I would think that if the wireless AP is not assigning addresses, the wired router would.

[Chavo]

Well obviously :)

The question is just my curiosity regarding the underlying procedure.

[MyndFyre]

Well, so an interesting question here: should I connect my switch to my wired router with multiple connections?  Will there be a bottleneck between 8-12 DHCP clients being served through one wire?

[Camel]

...but it does leave the open question (that I'm sure a good answer exists for) of how the AP manages the DHCP router <-> AP <-> Wireless Client connections.

Your question crosses OSI layers, so it's unanswerable. The AP doesn't know or care what DHCP is, or what IP addresses are. They have no relationship whatsoever.

Skip this if you already know what an AP is, and how that relates to the OSI model:
>>>


An AP (and I don't mean a router that has an AP in it; I mean the singular entity) doesn't operate at the network layer. It operates on the physical layer, in that it converts between "wired" and "wireless" traffic. There's also another entity that is usually (incorrectly) grouped in with the AP that converts between 802.1 and 802.11 (data-link layer) traffic. The reason that this is incorrect is that there's no reason you can't have 802.11 data on a wired network. This work is done on the CPU of the router in the case of the 300N, but it's important not to confuse the idea that they are separate entities.

An example of wired 802.11 traffic is those wireless things you could buy for the original XBox - when the box detected one connected, it would speak 802.11 instead of 802.1 over the wire, and then all the wireless dongle had to do was blast the signal over the radio. If those things could auto-negotiate channels (some of them could, but the cheaper ones required manually selecting the channel), they'd have been full-fledged APs.

Even if you use AP to mean both of these entities (and I will do so, going forward in this post), there's still no bearing on DHCP or IP - those are network layer protocols, and reside inside of the 802 (data-link) tunnel. The AP considers that stuff to be payload, and will never attempt to read in to what those packets mean.
<<<

An AP is the wireless equivalent of a switch. It knows about the data-link layer because it has to send the frames to the right physical location (in 802.11N, the 3 antennas are used to "direct" the wireless traffic), just as a switch uses MAC addresses and a routing table to send frames to the right physical port. This is why a MAC address is called a physical address.

By disabling DHCP on the router, and not using the WAN port, the router is effectively disabled, reducing it to a switch and AP. Placing a crossover between the 300N's switch and the other box's switch creates a larger switch, and makes the AP accessible to the entire LAN, including the router with the enabled DHCP server that's performing NAT. The wireless clients will be bridged in to the same LAN as the wired clients.

Well, so an interesting question here: should I connect my switch to my wired router with multiple connections?  Will there be a bottleneck between 8-12 DHCP clients being served through one wire?

Yes, there will be a 100MBit or 1GBit bottleneck, depending on the speed of the slowest port the crossover is connected to. Using multiple links won't help; the switch will pick whichever one it thinks is faster, but will not use both at the same time.

[MyndFyre]

So I need to run a crossover between the wireless AP and the wired switch?

[Chavo]

So I need to run a crossover between the wireless AP and the wired switch?

You don't need (or want) a crossover cable anywhere in this configuration.  A normal cat5/6 Ethernet cable in one of the non-uplink ports of your AP to any of the client ports of your router will be fine.

@Camel, that doesn't address my "question" at all but instead spouts of a bunch of network structure I'm already familiar with.  My efforts to dismiss my curiosity as just that and let the thread continue have obviously been fruitless so far.  You don't seem to understand what I was pondering and I don't have any desire to clarify it.

[Camel]

So I need to run a crossover between the wireless AP and the wired switch?

Only if you live in 1995. These days, switches will automatically compensate.

[MyndFyre]

So I need to run a crossover between the wireless AP and the wired switch?

Only if you live in 1995. These days, switches will automatically compensate.

Then why'd you say it?

[Camel]

It's still called a crossover, even if you don't use a special cable.

[nslay]

Myndfyre, you strike me as a power user who likes control of his equipment.  Don't buy a home-grade router! Either build your own (e.g. Intel Atom, Soekris, etc...) or if you have some Ethernet/Wireless cards in your spare parts drawer, go to your nearest dumpster and fish out an old P1/P2/P3. 
I use FreeBSD 7-STABLE on a Pentium 2 and it works better and is more solid than any cheap home-grade router from Best Buy.
My Pentium 2 machine has a 6GB harddrive, 96MB of RAM, 2 Ethernet cards and 1 Wireless card (Atheros-based).  The embedded boards generally have less!
1 Ethernet card goes out to the cable modem.  The other goes out to a 16-port switch.  I use ISC dhcpd as my DHCP server, FreeBSD's named as my DNS server, hostapd for managing 802.11 station mode (WPA2) and of course, sshd.  I have configured it to use a serial console lest the network breaks (it hasn't).  I use if_bridge to bridge my LAN ethernet interface and wireless interface.  I use pf with hardened rules for NAT and firewall, and securelevel=3 to harden the kernel from rootkits, prevent crucial userland tools from modifcation, and prevent firewall rule changes.  It is rock solid stuff!
I subscribe to FreeBSD-security mailing list for vulnerability announcements (generally there are a couple every 6 months).  I use portaudit to assess vulnerabilities in any and all installed applications.  I haven't had a chance, but FreeBSD also provides trusted computing mechanisms such as Apple/McAffee's audit (for fine grained logging), and Sun's OpenBSM, and capable of remote logging.  The kernel ensures that audit logs cannot be modified.

[Camel]

I did something along the lines of what nslay is suggesting for my fraternity house - but only because it was seriously necessary: home-grade routers can't handle 40 users. MF doesn't have that many users, and he's already got the home-grade hardware, so it would be rather pointless to beef up something that isn't the weakest link.


On a side-note, learning iptables is fun. Gives you a much better understanding about how NAT actually works, behind the scenes.

[nslay]

I did something along the lines of what nslay is suggesting for my fraternity house - but only because it was seriously necessary: home-grade routers can't handle 40 users. MF doesn't have that many users, and he's already got the home-grade hardware, so it would be rather pointless to beef up something that isn't the weakest link.


On a side-note, learning iptables is fun. Gives you a much better understanding about how NAT actually works, behind the scenes.

Yeah but MF is a power user.  I'd think he would want a Ferrari instead of Pinto.  Not like he lacks the technical expertise to do it either.

[Camel]

Do you think he would commute to work in a Ferrari?

If he wants to use any of the things you've listed, there's no reason he can't do that on his linksys router; enabling SSH is trivial on every model they've ever released (they do this intentionally). The only advantage to having a powerful machine instead of a dinky home router is the capacity of traffic that it can handle, and it is already unlikely that he will meet the limits of the dinky home router.

[iago]

Just because he _can_ do it doesn't make it a valuable use of his time/money.