I am about to purchase a networking solution for about 180 users and 10 servers.
My question is should I use a big modular switch like 4506 or buy 7-9 3750 switches and stack them together?
From a financial point of view the 4506 costs more than the stacked 3750.
From a financial point of view the 4506 costs more than the stacked 3750.
If that's a driving factor, the 3750 it is.
Pros on the 4506:
Dual Power Supply
Cons on the 4506:
Need a 4507 for Dual Supervisor
Oversubscription in the line cards
Pros on the 3750:
More switches can be added to the stack at a very low cost
Cheaper PoE option
Cons on the 3750:
You lose a switch, you can lose up to 48 ports.
I'm sure there are many other Cons and Pros but those are the only ones that came to mind at this moment.
Re: Oversubscription. *All* networks are oversubscribed. It's how you manage this over subscription when designing your network that will either make your users - and more importantly, management - happy or sad.
Re: Throughput. When stacked the 3750 - read: non "E" - is 32 Gbps switch, period. The 4500 Sup II+ is 64 Gbps but the throughput is only maxed when you have 5 blades running. I won't get into details here. That's a product architecture thing, see my recommendation below.
To the OP: If you really want to make some informed decisions about product selection you should spend some relatively insignificant money on a Cisco Live! (formerly Cisco Networkers Online) subscription. Watch the Catalyst 4500 and 3750 product architecture presentations.
I sure do. But for my org., at the access layer (end user that is), it really doesn't matter. We got a cost effective solution that exceeds our needs now and for the foreseeable future.
That's why I think that solid design based on good fundamentals combined with complete information about the products is very important. You can certainly throw money at the problem, buying more capacity/features than you need, any vendor would be more than happy to take your money.
So if you do, why you said this when comparing both products.
When stacked the 3750 - read: non "E" - is 32 Gbps switch, period. The 4500 Sup II+ is 64 Gbps but the throughput is only maxed when you have 5 blades running.
The 3750 only needs the 32Gbps when going to another switch while the 4500 uses/needs 6Gbps when going from the ingress switchport to any other modules or even in the same switchport as the packet has to traverse the Supervisor for forwarding decision.
But for my org., at the access layer (end user that is), it really doesn't matter.
OP is concerned about 10 servers as well.
That's why I think that solid design based on good fundamentals combined with complete information about the products is very important.
Agreed. That's what we are trying to provide.
You can certainly throw money at the problem, buying more capacity/features than you need, any vendor would be more than happy to take your money.
Hmm. That's how you feel if the OP decided to go with the 3750 route vs the 4500?
Technically not true. When stacked a frame on the 3750 (again non-E here) must traverse the entire stack, even if it's destined to a port on the same switch. This is changed in the 3750E family. I have the Cisco slide deck that documents this but I can't share it (EULA). I'm aware of the packet trace on a 4500. What I was saying there is an aggregate throughput factor of 2 in favor of the 4500. Again, this is product information that the OP should have to inform his decisions.
What are those servers doing? Do they need full wire speed? If so maybe consider a 6 port gig blade. I don't know really, see my last comment below.
That was more of a general statement. When if comes to the OP's specific needs, I don't know. I'll post info about troubleshooting and products here but I won't design the guy's network for him. That's where highly *paid* professionals like you and companies like yours come into play :-)
When stacked a frame on the 3750 (again non-E here) must traverse the entire stack, even if it's destined to a port on the same switch. This is changed in the 3750E family. I have the Cisco slide deck that documents this but I can't share it (EULA)
You are right. No need to share any private document. It's fully disclosed on its data sheet
The stack behaves as a single switching unit that is managed by a master switch, elected from one of the member switches. The master switch automatically creates and updates all the switching and optional routing tables. A working stack can accept new members or delete old ones without service interruption.
Placing the servers or any bandwidth demanding device in the master switch would circumvent any throughput limitation.
What I was saying there is an aggregate throughput factor of 2 in favor of the 4500
My math tells me the factor is 5-1 (32Gbps - 6Gbps) in favor of the 3750.
Ok, last thing I'll say about the throughput. You agree (I think) that the 3750 stacking makes the whole stack a 32 Gbps switch. Now, lets say you take a 4506 and put 5 WS-X4506-GB-T in the thing. You now have no "oversubscription." All the ports are wire speed. Now load the thing up bidirectionally, oh and don't forget the 2 on board gbics. The switch runs at 64 Gbps, aggregate throughput. The 3750 stack? Load it up any way you like with any stack configuration, it's still 32 Gbps. Now do the same thing with a 4510 with the same line cards and a high-end sup. More throughput. The 3750 stack? Still 32 Gbps.
I'm not at all saying that one's the better switch. I like the 3750s and they certainly have their place. For example, You can only run IP Base on a Sup II+ where as you can run Advanced IP Services on any 3750. So there's some software flexibility there. I was just noticing that the tread started off as a bit biased (i.e. the cost point) and wanted to make sure that the OP had all the info.
You've modified the hardware spec to prove your point, but that's a far cry from the OP requirements (180 users + 10 servers).
I don't think it's fair comparison :)
I was just noticing that the tread started off as a bit biased
Hmm.. I offered the Pros and Cons that came to my mind. You could've added your POV without problems. That's what these forums are all about. I noticed the bias coming from you :)
I'm not a sales person so I don't get a personal benefit if the OP buys the 3750 or 4500 solution. As long as he buys a Cisco Catalyst switch, that's all it matters :)
Was merely using it as an example of the scaling and that a maxed 3750 stack is stuck at the same forwarding rate no matter what you do. I also had to swap it out since the Sup II+ won't go in a 4510. The Sup V is about 7K more than the II+ but you get 3 more slots in the 10 which will cost you ~30K more in 3750s. Bottom line is the $/port is still in the 4500s favor. It's all academic anyway since the OP doesn't need 384 ports.
I personally have to disagree a little with the way the 4500s were designed. The 6 traces/slot can be confusing to people that aren't paying attention. Not to mention that 1 Sup II+ and 1 48 port gig line card is still just 16 Gbps. All that spare grunt and nowhere to run. Oh well.
Note to the OP: We've focused (oh gods have we focused) on the non-e series products. Unless its cost prohibitive to do so I would buy into the E series of whichever platform you decide to go with. I'm not going to rehash all of this with the E series stuff or compare E to non-E features but I think that by now you have enough feedback to make that decision on your own. If after all of that you're still unsure, its time to call the consultants.
I almost forgot. One thing that you have to consider is SMARTnet. Technically, the 3750s have a lifetime limited warranty so you can buy N+1 to get you a spare and save yourself some cash for the *hardware* support. The hardware replacement is best effort but with the spare it may be good 'nuff. Advantage: 3750. I'm actually a little fuzzy on the software upgrade policy for the 3750 so maybe Edison can unfuzz it? I do believe that you're not entitled to software configuration support on the base warranty. Again, Edison?
The software policy in the 3750 is the same as any other Cisco device.
If you have a CCO software contract, you can download any image you want.
Legally, you must purchase and register the image if you've decided to upgrade the IOS that was shipped with the unit.
I know on the 2960 that you're entitled to "Software updates at no additional charge"
Might there be a document that describes the differences in the base support for each family?
You can update the software for free on any Cisco device. Remember, update =! upgrade.
For instance, on a switch from 12.2(35) to 12.2(40) - same feature set.
The "legal" cost is when you are moving up on a feature set, with LAN Base offering in the 2960, you don't have much choice as it's a plain old Layer2 switch.
With a 3750, you can purchase the base image and upgrade all the way to a k9 full-featured image by downloading the IOS.
Regarding cost. In certain deployments there's a break even point and the chassis-based box will become cheaper. I recently purchased a WS-C3750G-48PS-S for ~9500. I've also bought a few 4500's recently. A 4506 with 2x2800 W PS, a Sup II+ and 1 48 port gig poe blade is about $13700. A fully loaded 4506 (with the above ethernet mod) is about 32K and a stack of 3750s is about 48K.
All prices are approx. and are my cost not list.
To compete with 7-8 (can't do 9 unless you split the chassis out) 3750s you'd have to get a 4510R and at that scale you'd should also seriously consider dual sups. The sups also become more expensive since you need at least a Sup V. With 384 poe ports you'd also have to bump the power supplies up. Is that more than the 8 3750s at ~$76000? I've not done that particular spec recently so I can't say.
"Is that more than the 8 3750s at ~$76000? I've not done that particular spec recently so I can't say"
No it's not as i did the same spec recently. I agree cost should be taken into account. There is a "break even" point where stacking 3750 switches becomes more expensive than a 4500 solution even with Sup V's. Will double check tomorrow when i'm back in work but from memory it's about 4/5.
For 190 ports, why 7-9 3750s? Is there a reason to exclude the 48 port models? Otherwise you would only need 4.
There's pros and cons to both series, although either will likely fulfill your need. Best perhaps for you to list out the various features that are important to you, assign weights to them, best score wins. (From your mention of a financial point of view, give adequate wait to the cost delta.)