Cisco 3750G (WS-C3750G-24TS-E1U) - Fiber Module Options

[utawakevou]

Got 2 of these switch stacked and there is some changes that we are going to undertake which will require us to utilize the whole 8 or 4 (2 from each switch) SFP ports. Just need some adivce on which particular fiber modules should I procure. Does this switch support 10GB of SFP ?

Thanks

[Reza Sharifi · Accepted solution]

These are 3750G platforms.  The uplink ports (4) are only 1Gig with SFP optic. Now, you can use Multimode SFP or Single mode SFP.

Here are the part numbers and descriptions for the SFPs

Also, make sure to use the correct fiber patch cord with each SFP type

GLC-LH-SM=

GE SFP, LC connector, LH transceiver

GLC-SX-MM=

GE SFP, LC connector, SX transceiver

HTH

[utawakevou]

Thank you very much for the prompt reply. Will take this into consideration when buying the modules. The other question I post is the support of 10GB over the SFP interface for this particular switch ?

[Reza Sharifi · Accepted solution]

Glad to help and thanks for the rating

Regarding the 10GB support.  This particular model does not support 10GB.  If you want 10GB for your uplinks, you need the 3750E or 3750X.  I recommend the X series, as they are more flexible.  With the X series, you can get a 4 port 1Gig module or a 2 port 10Gig module or a combanation of 1 and 10Gig ports.

Here is the datasheet for the X series

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps6406/data_sheet_c78-584733.html

HTH

[utawakevou]

Thank you very much Reza for your helpful pointers.

Much appreciated

With kind regards

[utawakevou]

Hi Reza,

Sorry its me again. Am not sure whether you are familiar with HP as my setup at the moment is Im linking up the Cisco 3750 stack to a HP Procurve 4204vl using UTP(link aggregation - 4GB). Our change will involve linking up the Cisco stack to the 4204vl via fiber. I havent done this in our environemnt where I link up HP and Cisco via fiber. We have a single mode fiber and as you point it out, I will need GLC-LH-SM for the Cisco. So thats okay with the Cisco.

Just need help in deciding which module to buy for HP that will be compatible with  the Cisco-GLC-LH-SM. Have gone through the site and have seen this one for HP - HP X121 1G SFP LC LH Transceiver (J4860C)

Thanks for all the help

regards

[darren.g · Accepted solution]

utawakevou wrote:
Hi Reza,
Sorry its me again. Am not sure whether you are familiar with HP as my setup at the moment is Im linking up the Cisco 3750 stack to a HP Procurve 4204vl using UTP(link aggregation - 4GB). Our change will involve linking up the Cisco stack to the 4204vl via fiber. I havent done this in our environemnt where I link up HP and Cisco via fiber. We have a single mode fiber and as you point it out, I will need GLC-LH-SM for the Cisco. So thats okay with the Cisco. 
Just need help in deciding which module to buy for HP that will be compatible with  the Cisco-GLC-LH-SM. Have gone through the site and have seen this one for HP - HP X121 1G SFP LC LH Transceiver (J4860C)
Thanks for all the help
regards

The important thing when matching SFP's from different vendors is the wavelength they support.

The GLC-LH-SM from Cisco is 1310 nm wavelength, designed to run up to 10000 meters on single mode fiber - your HP quoted module is a *much* higher power rated version - the Cisco "LX" equivalent designed for up to 70000 meters on single mode fibre - I'd recommend you go for the HP J4859C, which is a matching power level to the Cisco unit.

This assumes, of course, your cable run is less than 10000 meters. :-) if it's more, then you've got the wrong Cisco SFP module.

There is a lower spec module for both Cisco and HP, for range up to 550 meters (depending on fibre specifications), but they're designed to only work on multi-mode fiber, so are no good for your installation.

Cheers

[utawakevou]

Thank you very much for all the help and advice. I now understand it

[grussell66]

I was wondering if its possible to use a

Gigabit RJ45 Copper SFP Transceiver Module?  In other words I need a Gig copper connection instead of fiber. 

[Joseph W. Doherty]

You can if the SFP support matrix, for your device, notes that it's supported. (If it's not supported, it might still work if you enable unsupported SFPs.)