Mark Lanctot;173957 Wrote: 
> Hmm?  I thought it was?
> 
> NAS (SlimServer) - SB (acting as bridge) to router, one wireless hop.
> 
> Router/AP to another SB, wireless, 2nd wireless hop.
> 

Well, my bad, that will teach me to respond without reading more
carefully, and I know better. Sorry.

"router" confused me. A wireless access point (WAP) can be either a
bridge or a router. In my network my WAP is a bridge. The SB is a
Wireless Station (STA), either end device or bridge.

So, let's take three cases.

1) Peer to Peer mode. Topology:

SlimServer - STA(SB,Bridge) - 802.11g - STA(SB)

2) Infrastructure mode. Topology:

SlimServer - STA(SB,Bridge) - 802.11g - WAP - 802.11g - STA(SB)

3) LAN topology:

Computer - STA(SB,Bridge) - 802.11g - WAP - 802.11g - STA(SB)
WAP - LAN - SlimServer

(1) there is no routed hops and 1 wireless "hop". Hops usually mean
routers (decrement TTL and forward). If you are running 11g and have
good wireless connectvity you should have no issues in this mode.
STA(SB) sends request to SlimServer, it flows STA(SB) direct to
STA(SB,Bridge). Then the bridge function looks at the packet, sees the
MAC is for the Slimserver, looks at its MAC forwarding table and sees
the SlimServer is on the wired port, and forwards it out the Ethernet
wired port. The SlimServer responds, sends a packet to the
STA(SB,Bridge), who looks at the MAC header, sees that it needs to go
wireless and sends it to STA(SB).

In this case, you should get usual speed of 24 Mb/s or peak speeds of
54 Mb/s, well able to support a FLAC stream at .3-1 Mb/s plus headers.

(2) there is no routed hops if the WAP is a bridge. If the WAP is a
router, and the packet is STA to STA *there is no routed hop* (meaning
no TTL decrement, its on the same IP subnet). There are 2 wireless
access network "hops". Path in this example is the STA(SB) sends to
WAP, who retransmits to STA(SB,Bridge). STA(SB,Bridge) sees the MAC is
for the SlimServer which is out the Ethernet interface, and forwards
it. Reply from SlimServer goes to STA(SB,Bridge), forwards to WAP,
forwards to STA(SB). 

Since 11g has a peak bandwidth of 54 Mb/s and usual speed of 24 Mb/s,
you should have no problem getting 10 Mb/s thoughput (half of the AP
usual speed).  

(3) There is one wireless "hop" from SlimServer to SB, the usual
configuration. 

So your example is (2), right? Given the forwarding outlined above, and
a usual .11g speed of 24 Mb/s (peak speed of 54 Mb/s), and FLAC
streaming at .3-1 Mb/s (plus header overhead) you should not have
trouble supporting a FLAC stream from SlimServer to SB. 

However, if you have marginal wireless connectivity or use 11b, data
rates plunge massively and this will definately be a problem. This is
likely the source of connectivity problems when using topology (2). Set
the WAP to .11g mode only, and check wireless strength. If necessary,
buy high gain antennae for the WAP to help.

Another point you made confused me too:

Mark Lanctot;172337 Wrote: 
> I'm amazed this all works?
> 
> Because this is a convoluted wireless arrangement.  Say the SB3 wants
> to send something to SlimServer.  It can't do this over its crossover
> cable because you've told it to use the wireless interface and bridge
> the Ethernet port.  So it looks for SlimServer out over the wireless
> interface.
>  

This is what I was really responding to. See my packet flow above - the
Bridge determines which side the MAC address is on.

I hope this fixes my reply...


-- 
Eric Carroll
------------------------------------------------------------------------
Eric Carroll's Profile: http://forums.slimdevices.com/member.php?userid=9293
View this thread: http://forums.slimdevices.com/showthread.php?t=31850

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