John Navas <spamfilter0@navasgroup.com> hath wroth:
>>Speaking of cheap routers, here's a chart of the number of
>>simultaneous connections apparently allowed by various cheap routers.
>><http://www.tomsnetworking.com/lans_routers/charts/index.html?chart=124>
>>Some of these routers would not work with 8 apartments (and probably
>>16 wireless users).
>Even the high end of that range is probably going to be a problem if
>more than one family uses peer-to-peer file sharing at the same time.
Peer-to-peer can exceed the number of available streams that the
router can handle. Strangely, I've tested bridges and access points
(not router) for the number of MAC addresses they can handle. Some
are intentionally restricted (i.e. workgroup bridges) to 4, 16, or
whatever. Some are limited by available table size (WAP11 maxes out
at 30). Most have some mechanism for clearing out stale entries. The
speed of which these can be cleared seems to be what limits the
maximum number of MAC addresses. If the access point is fast, it can
handle a large number because the access point dumps them as fast as
the MAC simulator software can generate them. If they're slow, the
table fills and the number of MAC's is limited. There's probably a
connection between the number of streams in the router, with the
number of MAC addresses in the access point, but offhand, I don't know
what it might be. I'm also not sure if the access point and the wired
side router share the same MAC address tables.
>Another issue is isolation -- it's probably a bad idea to have all the
>families on the same network, and most "bargain" routers don't have
>isolation ability.
True. Linksys WRT54G has "AP isolation".
Cisco has it as:
Network Interfaces -> Radio0-802.11G -> settings ->
(PSPF) Public Secure Packet Forwarding -> Enable
Hot spot specific hardware and some access points have this feature.
It's also sometimes called "client isolation", "wireless to wireless",
or part of "port isolation". This feature became a major requirement
for my neighborhood LAN when some of the local kids decided to use it
as a repeater for their non-TCP/IP gaming network.
>And I wonder if a single wireless access point will be able to penetrate
>all the walls.
For apartments and some office buildings WISP service, I try to
arrange for the AP to be outside the building. It's much easier to
"illuminate" the outside wall of the building, and go through the
windows, than to convince wireless to make right angle turns down
hallways and go through thick doors or walls. This is not possible
with office or home WLAN's that require a wired backhaul to a DSL or
cable modem, but works nicely for community and apartment networks
where everyone shares the same broadband backhaul.
>Methinks the Cisco price is affordable for the target application and
>needed feature set.
A single router for 8 apartments is possible but problematic. It
really depends on the usage pattern, topology, and building
construction. If it's a concrete block building, and outside
illumination is impossible, then it might require more than one
wireless access point to cover the 8 apartments. That would raise the
cost to prohibitive. Without details, I don't think either of us
could offer an optimized solution. At some price point, the various
wired options (HomePNA, HomePlug, WiFi over CATV, etc) become viable.
>Another option is the ZyXEL G-4100, which has both authentication and
>hotspot feature set, but that's still $400.
>
>But if price *really* is that much of an issue, then my recommendation
>is ZyXEL Z-2000 Plus (about $140), because of its built-in PEAP.
>(I don't think PSK is at all suitable for a multi-family environment.)
Yep. A good choice for security. Administering a neighborhood WLAN
or shared network is a PITA. The 2AM phone calls asking "is the
internet down" is enough to make me reconsider the option.
Neighborhood relations and the ultimate fair billing system are other
problems. Anything that keeps the phone from ringing is a good thing.
Therefore, security should be a non-issue which means WPA-RADIUS.
>I buy factory refurbished or clean used notebook computers still under
>factory warranty, which lets me enjoy top-of-the-line quality and
>support (albeit 1-2 cycles back) at bargain prices. My current T41
>(still under factory warranty) cost me all of $550.
Yep. Same here. I buy refurbished:
|
http://www.delloutlet.com
| <http://www.costco.com/Common/Category.aspx?whse=BC&Ne=4000000&N=4017754&Nr=P_Ca talogName:BC&cat=4774&Ns=P_Price|1||P_SignDesc1&to pnav=>
|
http://www-132.ibm.com/search/refurbished.html
Except for some shipping damage, my savings and batting average has
been quite good. The 30 to 90 day warranties seem to be good enough,
but I've never had to use them. However, these are for my customers.
I get their obsolete computers for next to nothing.
--
Jeff Liebermann
jeffl@comix.santa-cruz.ca.us
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Wireless Router? 
Linear Mode
