Need some information on LAN Design.

[Umesh Shetty]

Hi Team,

I need some information on branch office network infrastructure design for 500 users with the below requirement. I need to know what flavour of access and core switches should I use. Can someone list down the points that I need to consider while deciding on the infrastructure and the kind of analysis that needs to be done before reaching a conclusion.

User will use :

E-mail Lotus notes

Microsoft Office communicator

Internet

Genral interanet services.

I addition each user will use VOIP

Video will also be a part of the LAN.

Thanks in advance

Regards

Umesh Shetty

[brett.harding]

Hi Umesh,

For the access switches I would recommend stacking 3750-X series switches across your departments / floors with 1/10G uplinks leading back to a ditribution/core switch. The 3750-X switches provide redundancy, are stackable, offer a high port density with support for IP phones (POE). For the distribution/core switch you can look at something like the 4500 series switch which offers redundant supervisor modules, power supplies and can provide 1/10G capable downlinks to your floor switches. If the site is not going to grow beyond 500 users then a 3750-X stack could also be used for the distribution switch.

Hope that helps.

Brett

[Simen Ringstad]

As always, it depends. What is your need for redundancy, features, and of course budget. How much traffic to you expect and how will it flow? Identify potential bottlenecks.

How is the wiring in the building? With high capacity wiring closets stacking or chassis switches is a nice touch to simplify managment. I see little point in paying for stackable switches if you end up with one or two in each wiring closet. Stacking can also increase redundancy.

How much of your traffic will be between hosts in your LAN and how much will traverse your WAN. It's no point in giving each user gigabit with 10 gig uplinks if the all traverse the same 100 megabit WAN-link.

POE is more or less a given, unless you are on a really, really, tight budget. If your users use IP-phones you are going to need POE on all ports (2960S-F48FPS-L). If they use soft phones you could save a little money by using the 2960S-F48LPS-L as POE will only be used by WLAN AP's and the odd phone or other device.

Good luck!

[JohnTylerPearce]

I agree with Simen. I would go with 2960s (48 port) for the access switches, and run a collpased core design. I would have L2 to the Core/Distribution, and from there to the corporate office.

I also agree with Simen about the speed and traffic.

Are the users going to be going to the corporate office for internal resources or will they have servers on site?

If so, it depends on your WAN link.

You could just have a L3 MPLS VPN back to corporate with your internet access through corporate, or Site-to-Site VPN back to corproate, and you also use the same WAN connection for internet, whoever the local ISP is for that area.

Personally, I would recommend 2960s [48Port PoE] going back to a stack of 3750s, for redundancy.