Check my topology!

Bakedgoods

Bakedgoods

Bakedgoods

Capodecina
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Not sure if the router with the WAN link should also be connected directly to the core switch?

Feedback is appreciated :)

TopCheck.jpg
 
I have created a redundancy model but given the budget it's a recommendation for future rather than for this phase.

Each of the distribution switches will have their own subnet and the devices above will be contained within one/two subnets (core switches/routers) can't decide.

I'm more concerned at the moment with getting the topology correct rather than protocls etc.

Single mdoe fibre links between all switches and devices.

I wanted to seperate the wan link from the main router incase the router breaks. With topology 1 I would be able to have the WAN router act as backup for the LAN router should the LAN router break.

If I went with topology one and linked both routers couldn't I effectively distribute the load? The WAN link would still go to only one router though.

I might just opt for Top2 initially and use one router at the top. There wil be a firewall between the router and the WAN. As for the kit, I haven't spec'd the kit yet but we are talking typical Cisco mid-level switches, 24 port 3750's? There is only going to be around 67 users initially but obvious potential for expansion.

Any ideas?
 
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I think i'm going to remove one router and just have one router at the top which also has the WAN link.

I have created another topology which offers high resilience but the cost of it can't really be justified at this stage.
 
I'm not too knowledgeable about layer 3 routing. As I understand you can not 'talk' to another subnetwork unless you pass through a router, i'm guessing switching at layer 3 means the switch will do this routing?

I'm going to go for one router initially.

What do the 3750's offer over the 2960's?

Aill fibre is going to be single mode, all links on that diagram will be single mode. 8 core cabling will be in place but only 2 cores will be patched initially.

Does that sound sensible?

I'm not sure what core switch to use as I will need quite a few fibre slots.

Thanks everyone you are being a big help :)
 
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What's the advantages of using a layer 3 switch over a router? I know most networks have layer 3 core switches but i'm not aware why?

Thanks for the help I do appreciate it.

The topology was created in Visio, you have to search for 'router' and 'switch' if you want symbols like that.
 
That makes sense thanks a lot, i've just had a quick further read on them now.

How would a firewall usually fit into a topology in terms of its positioning and the WAN?

You guys have been very helpful, there's a lot of knowledge around these parts :)
 
Well, i'll be using 6 cores from 5 of the distribution switches. and 4 cores from the other.

Only 4 cores will be patched, with the other two ready for future use. That still means I need to patch 24 single mode fibre cables into the core switch, can you recommend me a layer 3 switch for this kind of task?
 
Thanks very much i'll check it out and try spy some prices.

I'm guessing the standard switch software will not be for layer 3 and the correct image will need to be installed?
 
Cheers for the help, it's been sound advice.

I'm still unsure on where to have the firewall sitting in all of this.

My topology now is basically...

ROUTER (WAN LINK)
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LAYER 3 SWITCH
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DISTRIBUTION SWITCHES
 
What about using Cisco 2950's for the distribution switches?

I'm not quite sure I need a 3750 because the 2950's are stackable. My distribution switches will all have 4 core single mode fibre heading to the core switch. Ideally they will need to all be 24 port as well.
 
What's wrong with stacking at distribution level?

If you didn't want to stack would you have to do something like this and include edge switches?

CORE SWITCH
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EDGE SWITCH
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Distribution #1- - - Distribution #2

If I didn't stack and adopted the above I would need to lay another cable to the edge switch. Although I suppose in reality the edge switch would be fairly close to the distribution switches.

Do correct me if i'm thinking wrongly here...
 
Sorry I understand thast I just made a mistake with the terminology. Thanks for your advice it's proving very useful.

The reason I spoke about stacking is that I was unsure how much it was cost to lay and terminate a new fibre to a new access switch compare to adding a new switch in a stack. Obviously you can't keep stacking if you don't have enough bandwidth to support the extra users.

So distribution switches operate on layer 3? When this happens i'm guessing the purpose of the core switch is basically to link the distribution switches?

And an un-related question...

As I understand it's at distribution switch level where you would be looking to create resilience initially? For example having two core switches and each distribution switch has a link to both cores?

Thanks again!
 
As it stands I can't really justify having more than 6 cores run as that's easily enough bandwidth for current requirements and any foreseable future requirements. Only 4 cores will be used initially though.

It looks like it will be better to opt for 2960s. If another switch is added it would only have one pair available so I suppose I can justify 8 core for resiliency.

That all makes lots of sense thanks a lot. Now I need to find a firewall/router for the wan connection.

Thanks again!
 
If I use 8 cores for each fibre link (not all will be patched) i'll potentially need 48 available fibre ports. That would take a 4x3750 switch stack yeah?

Just need that then the gbics!
 
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I totally forgot about that! I've removed it lol.

Thanks i'll have a nosey around, thanks for your help it's been really useful and interesting. How did you learn everything? Degree and work experience? Just through work?
 
That's pretty cool :)

I desperately need a 1U patch panel for Visio but I can't find anything anywhere, don't suppose you can be of any help?
 
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