PoE for 802.11n

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Bakedgoods

Bakedgoods

Capodecina
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So what are you doing or planning to do regarding the PoE requirements of 802.11n?

Cisco are offering the ePoE which they say provides enough juice to fully power 802.11n APs with a full feature set, available on all catalyst switches from the middle of the year (3750-E does this already)

The other alternative seems to be using 802.11n products with a reduced feature set so that they can function with the current PoE standard?

What i'm digging at really is... if you make a mistake now with switch selection (the new PoE standard isn't out yet..), you may be in a bit of a mess when it gets round to upgrading to 802.11n.

Have you given this much thought?
 
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It's not, but vendors have been bringing out draft solutions for a little while (they supposedly will support the final standard when it's set through a firmware update)
 
I'm just considering the implications if new PoE switches were bought to support VoIP, but these switches eventually turned out to be insufficient for powering 802.11n in the future.

Basically future proofing infrastructure :)
 
I suppose by having chassis based switched at the access layer it isn't really a problem to you, because you'd simply be upgrading line cards not worrying about replacing entire switches.

How much would a typical 6500 acess layer switch cost? Say 48 port 100mbit or 1Gbit, with supervisor modules and power etc? Roughly?

6500s are a pretty serious and costly solution for access layer stuff it seems.

If you're waiting for the next standard though surely that's going to be a long time, and people will be hinting at implementing 802.11n when second generation products are released?
 
Do any of these modules support Ciscos ePoE that is capable of powering 802.11n? How will the chassis switches cope with the eventual new PoE standard? Will you just need new line cards or new PSUs as well?

I'm just trying to think a little forward... obviously 802.11n isn't ready but in the future there's a possibility, so i'm wondering how to factor this in and future proof the access layer.

For example... someone buying new PoE switches for VoIP and 802.11g, but then 2-3 years down the line has to replace these switches because the PoE isn't good enough for 802.11n.

Cisco's enhanced PoE is supported by the 6500s, 4500, 3750-E, and 3560-E.

I can't see the next stnadard after 802.11n being out for a LONG time, and it's likely by then it will be time to upgrade/replace switches and the new ethernet standard should be around? Or at least that's how I imagine it should go :D

Thanks for the input
 
Well the increased range of 802.11n is an immediate one as it reduces the number of access points you require. Ultimately it makes for a pretty good shift and lift network. For example, if a department or group of users go into a new building, or some temporary building then it's cheaper than installing cabling to desktop if it doesn't exist

I remember you saying that a 6500 with redudnant supervisors is regarded are more reliable than typical access layer solutions like a 2960 or 3750?

I'd love to get your e-mail so I can trouble you on there from time to time, if you wouldn't mind ha-ha...

Much appreciated :)
 
Yeah very valid points :)

I don't have a price list (i'll get one), but i'm curous how the think the cost of an access layer solution for say 400 ethernet (100mbit to desktop) would fair compared to a 3750 or 2960 solution.

Been trying to find something online but it's a mare. Would be really nice if you could select a chassis, then the modules and get a cost :D

I'm guessing the licencing is cheaper than having lots of smaller Cisco switches?
 
Hmm, not too sure exactly what modules I should be adding with the exception of ethernet ones. There's a pretty large variety and a massive difference in cost among the supervisors.

At the moment i'm just trying to establish a cost comparison between using a 6500 to support 400 ports (obvious fibre link to distribution too) compared to a more common approach.

It looks like effectively the hardware is more expensive initially, but the per port cost over a few years is actually cheaper?
 
Yeah i've tried basically pricing one up at the different was about £17,000.....

2xPSU
2xController
4x48 Port Ethernet
1x6509 Chassis

£30,000 or so...
 
Obviously for small offices or whatever then the 4500s etc are out the window, but i'm thinking along the lines of one which has upwards of 400 network connections.

How does the licensing work? In the above example would it be cheaper to licence a 4500 with say 4x48 port line cards and two supervisors, rather than 4x48 port 3750-E's?
 
Hmm, I think the business case wouldn't be paticularly strong then.

I downloaded a PDF off the Cisco site which shown the initial purchasing of a 6500 to be more expensive, but the cost per port over the space of 5 years was cheaper than a lower end solution.

I'll ask some questions and find out more about the support and IOS costs, I just assumed that it may be cheaper because essentially you have less switches..
 
From what I can tell, the wireless 802.11n vendors will have reduced power to comply with current standards by the time 802.3at finally arrives.

Siemens have a 802.11n products running at full capability using current 802.3af PoE, so it looks like it might only be a matter of time before the remaining vendors follow.

Or will it?

It seems the others might take a while as they all use an Atheros chipset, which is where Siemens differ. So they are basically all depending on Atheron to reduce the power consumption
 
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