PoE for 802.11n

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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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If it was me I would wait until it is fully certified, althugh the fact that Cisco are talking about measures to support it suggests it must be close

Do you have to buy some new switches straight away or could you wait for a while?
 
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 :)
 
Personally my approach is not paying any attention, the N standard has been in development for so long and I'm not yet convinced it offers anything over 11g for most enterprises. You want speed you hard wire so nothing changes there, and more and more applications are becoming server based with laptops and desktops little more than thin clients. Given that I'm happy to stick with 11g for now, skip 11n and go for whatever standard turns up after that (when we'll be replacing switches anyway)

If there was some pressing reason to upgrade we could always just stick a couple of new line cards in our switches (the beauty of using chassis based switches, no need to replace chassis, controllers or power supplies, just add some of the new line cards!)

Then again, we're hardly representative, wireless isn't a big thing for us at all and likely won't be except in the office.
 
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?
 
Wardie said:
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?
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The very cheapest 6503 with a low end supervisor and 48 port gig line card with POE would come out at about £6500, you could slot in a second 48 port line card of coarse the cost per port starts to become more reasonable...

We tend to use much bigger ones with redudent supervisors (6507/6509 most frequently) so the cost per port drops even more.

Of course the 6500s are the top end for this sort of thing...a 4503 with 48 port gigE POE line card, basic supervisor and power is about £5k and will most of the same things, you just can't add things like wireless controllers or IDP blades...
 
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
 
Wardie said:
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
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No idea if they support ePOE, they're just off the price list I had hanging around. You might need new PSUs depending on the power draw, you can get various options already depending on your needs, we tend to take pretty high end PSUs as a form of future proofing. Even the smaller ones are 1400w+ though so I doubt you'd need to upgrade in most circumstances...

In the end, you can't future proof if the kit doesn't exist yet and you have to question the need for it in the future. Enterprises won't upgrade to 11n because it exists, they'll only do so if there's a sound business requirement to do so and right now I can't see one coming up. Also, the switches only have a lifetime of 3-4 years for most companies before they get refreshed with new equipment...
 
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 :)
 
Wardie said:
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 :)
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Well true it's cheaper than cabling to the desktop but I don't know of any enterprise thats gone wireless only yet. Most desktops don't even have an option for built in wireless (I'm going on HP here but I'm fairly sure dell don't either) and you're hardly going to use netgear cards in that environment. There's also the cost of support to consider, CAT5 to the desktop doesn't go wrong very much, wireless has a bigger support cost associated.

Anything with multiple supervisors and power supplies is going to be available more of the time when it comes to access layer solutions. It's not more reliable, you could have the same number of failures but they don't affect users is the difference. The only failrue which affects users is line cards, which are made as simple as possible so they have a high MTBF.

Trouble me by email all you want, my address is in my trust (as is MSN but I'm never really on there these days..)
 
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?
 
Wardie said:
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?
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For pricing, look at a hardware.com (I don't think they're really a competitor to OCUK somehow), UK pricing for virtually all cisco stuff. It's a bit more than we pay but a good guide none the less if you don't have a reseller price list to hand...
 
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?
 
Wardie said:
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?
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Can be, for access layer switching you'd only need the most basic supervisor, the high end supervisors can run ISP core networks. That, power supplies, chassis and line cards would be all you'd need for a basic setup. Unless you need a 6500 specific feature though, you'd be better off with a 4500 which does much the same with a few less features for cheaper.

To quote your example though, 48 port 3750E series switches with POE cost about £7k each, so 4 of them is coming close in price while being less resilient and possibly more hassle to manage (you could always stack them and manage them as one unit of course).

There are situations where standard fixed config units like the 3750 are better of course, chassis switches aren't always the best option out there if you don't have thousands of users...
 
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?
 
Wardie said:
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?
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Depends what you mean by licensing, the IOS feature set is for the supervisors only. If you mean support then it depends as I recall, if you only have a single 4500/6500 then it'll likely be more expensive for support.
 
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..
 
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