[asterisk-users] PoE switch recommendations?

[Alexander Lopez]

Your math is correct but the application is incorrect.

The OP requested a switch with "solution with VLANs, PoE, and QoS?"  By that they would be using the VLANS and QoS for separation of Data / Voice.

Gb uplinks are very useful in Data applications......

Alex


 Kindly consider the environment before printing this e-mail.

> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-
> bounces at lists.digium.com] On Behalf Of Gordon Henderson
> Sent: Monday, October 06, 2008 11:29 AM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: Re: [asterisk-users] PoE switch recommendations?
> 
> On Mon, 6 Oct 2008, Ken D'Ambrosio wrote:
> 
> > Hey, all.  We're rolling out VoIP, and I'm wondering about PoE
> > recommendations, as we're going to have to replace our current network
> > equipment.  My first inclination would be to just plunk down the cash
> and
> > do a Cisco system, but I'm relatively certain that would get shot down
> by
> > finance.  Any recommendations for a couple-hundred-port solution with
> > VLANs, PoE, and QoS?  Don't care much if it's in a single chassis or
> not,
> > so long as it has Gbit uplinks.
> 
> I'm curious as to why you want Gb uplinks on the switches?
> 
> If we assume 100Kb/sec per phone .. (gross rounding, using 100Kb/sec per
> phone, rather than ~80 - make the sums easier and builds in a margin) 10
> calls per Mb/sec.
> 
> So for a 24-port switch, 24 phones all talking to 24 extensions off that
> switch, the max the uplink port is going to be pushing out is 2.4Mb/sec.
> 
> For 200 extensions, say 9 x 24 port switches, with a single top-level (non
> PoE switch) switch with the PBX plugged in along side the 9 downlinks,
> that single PBX link will be carrying 2.4*9 = 22Mb/sec if all phones are
> in-use at the same time (and the PBX is carrying media)
> 
> Now you may not want to build the network like that, but it seems that Gb
> is overkill just for the VoIP side of things. (And with that many
> extensions, I would suggest keeping all the phones on one set of switches)
> 
> (Then again, it might not be possible to get big PoE switches without Gb
> uplinks, so it might be a moot point!)
> 
> So satisfy my curiosity - why Gb uplinks?
> 
> Cheers,
> 
> Gordon
> 
> _______________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
> 
> AstriCon 2008 - September 22 - 25 Phoenix, Arizona
> Register Now: http://www.astricon.net
> 
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users