Connecting Two Cisco Switches Using a fiber cable.

[Vijay Chawla]

Hi Experts,

I have a basic knowledge of network and need some help.

I need to connect 4 Floor Building with 4 Cisco 2960 - 48 ports switch each other and it needs to be through a fiber. So all PCs connected to each switch would reach the LAN/WAN from the other switch. (attached is the image here with)

I see that the 2960 has 2 SFP ports each port of each switch should connect each other or how?

My simple question is:

1. What cable / patch code I have to use = Single-mode or Multimode? ( distance for each switch will not more then 25 mts)

2. Do I have to use SFP or SFP+ module?

3. What kind of SFP/SFP+ module I have to use = Single-mode or Multimode?

4. What kind of connector should patch code have = LC / SC or ?

5. How to connect each switch with redundancy like ...each switch should be interconnected with each other or I have to choose Cisco

3750G which has more then 2  SFP ports (option#1 & opetion#2 = attached here with) = Kindly advice..

Kindly advice the best practise for connecting cisco switches over fiber.

Any help is appreciated!

Thanks in advance..

[Leo Laohoo]

Both options 1 and 2 are not good.  Why?  You run the risk of generating a network loop.

So each floor has one switch?  And you want redundancy?  The only redundancy you'll get is when a fibre optic cable/SFP fails.   Ok?

My opinion is this:  Run TWO fibre optic cables to each floor.  Put both fibre optic run into a Layer 2 Etherchannel. 

[Vijay Chawla]

Thanks leolaohoo for your propmtp reply,

I have a bit understanding as below:

1. to get rid of network loop I have option#3 attached here with = kindly advice.

2. Yes you are correct in each floor I will have one cisco switch & redendancy with Fiber/SFP is okay with me.

3. 2 Fiber cable connecting in each switch togather configuring with EtherChannel...so I have to choose the switch like 3750 which has at least 3 SPF ports = am i correct? Kindly have a look on Option#4

also i will need SFP module according to no of fiber cables=correct?

Kindly advice...

[Leo Laohoo]

1. to get rid of network loop I have option#3 attached here with = kindly advice.

Option 3?  Sure this may work.  But where is your "redundancy"????  Another thing, have you considered what the severe implication would be if the switch nearest to the core switch fails?  That means all the switch beyond that is royally s_crewed.

My other option of each floor, running a minimum of two pairs of fibre to the distribution switch, and then connecting each run into an etherchannel is possibly the best bethod.  You get a loop-free link plus dual links, one for redundancy.  If one link fails, the other will take over without any human intervention.

also i will need SFP module according to no of fiber cables=correct?

Yes.   You will need two pairs of SFP and two pairs of fibre optic patch cable.  There are some questions you need to fill in:

1.  What kind of fibre optic runs will you be doing?  Single-Mode or Multi-Mode?

2.  What category of fibre optic runs?  OM3?  OM4?

3.  What termination type will you choose to terminate at the FOBOT?  SC?  LC?  ST?

[Kazim1998]

Quick question
Wouldn't Spanning Tree Protocol
Prevent a loop in this setup?

[Leo Laohoo]

1. What cable / patch code I have to use = Single-mode or Multimode? ( distance for each switch will not more then 25 mts)

At that distance, Multi-Mode (MM) will do fine.  But only you can answer what your existing cable is.  I've seen an 11 story building with single-mode fibre being run.

2. Do I have to use SFP or SFP+ module?

You need two SFP per cable run.  One for the 2960 and the other for the 3750.

What kind of connector should patch code have = LC / SC or ?

The SFP will have "LC".  I can't determine whether or not your FOBOT is SC, LC or ST.  So you'll have to answer that piece of the puzzle.

[Vijay Chawla]

Hi again.

1.  "But only you can answer what your existing cable is...." in fiber (for switch connectivity) I have not bought anything....in coper (for PC connectivity) I am planing to buy CAT6A

2.      no of SFP in Option#3 = 8 SFP (for Cisco Switch) = also advice the no of the fiber cable i will have to run?

2.1   no of SFP in Option#4 = 16 SFP (for Cisco Switch) = also advice the no of the fiber cable i will have to run?

3.     I have not yet desided for any FOBOT. = advice the best one?

thanks in advance...

[Leo Laohoo]

I have a basic knowledge of network and need some help.

2.      no of SFP in Option#3 = 8 SFP (for Cisco Switch) = also advice the no of the fiber cable i will have to run?

Choose the design you want before you (not me) can answer this question.  No one here will be irresponsible enough to "spoon-feed" you the answers.  You'll come up with the solution and potential parts list and we can assist you by giving you feedbacks.

We are happy to help you learn only if you are happy to learn.

I have not yet desided for any FOBOT. = advice the best one?

It doesn't matter.  You choose.  I have no preference.

PS:  Your line of questioning, frankly, is beginning to sound like this "project" is actually a school work.

[Phil Minneci]

I had the understanding that SFPs were typically 10/100/1000M while SFP+ support 10G.  At least that's how it is in our product line.

[Leo Laohoo]

I had the understanding that SFPs were typically 10/100/1000M

Interesting.  I've never seen an SFP that can go as low as 10 Mbps.

Fibre optic modules (SFP or GBIC), are mandated by IEEE to support only one speed.  If you want 100 Mbps, you need to get an SFP that only supports 100 Mbps.  If you want 1 Gbps, you get an SFP or GBIC that only supports 1Gbps.  I don't believe there's a commercial-grade SFP or GBIC (that I know of) that can support both 100/1000Mbps fibre optic.

[Phil Minneci]

Ok, maybe not 10 Mbps...☺

We use Finisar SFPs that are muli-rate. Actually, they support both Ethernet & SONET/SDH rates. I suppose it depends on the eqpt capabilities as well.

Sent from Cisco Technical Support iPhone App

[Leo Laohoo]

We use Finisar SFPs that are muli-rate. Actually, they support both Ethernet & SONET/SDH rates. I suppose it depends on the eqpt capabilities as well.

Possibly.

Sorry, I'm saying you're a liar.  I'm just saying I haven't heard of this feature before.

Just saw this.