Q
Problem solve Get help with specific problems with your technologies, process and projects.

# GBICs and fibre cable

There are short wave and long wave GBICs. What is the maximum distance you can run the fibre cable with each? And, why would someone want to use copper GBICs and cables?

This is discussed in pages 346 to 350 in Building Storage Networks, 2nd edition.

Despite the way this information is normally presented, you can run cabling to all kinds of distances, however, the FC spec calls for certain max cable lengths that will support the max error limits.(10 x-12). Also don't expect vendors to support problems if your cable lengths exceed the spec.

The limiting factor is not the GBIC, it is the internal diameter (ID) of the cable - and the laser technology used. In general larger IDs, disperse the signal faster - resulting in shorter supported cable lengths. Here are a few specs for 1 GB FC (yes, 2GB FC is different and shorter):

• 9 micron (used w/ long wavelength lasers) 10,000 meters
• 50 micron (used w/short wavelength lasers) 500 meters
• 62.5 micron (used w/short wavelength lasers) 300 meters

There are also special long distance lasers that exceed the supported distances by a large amount.

If you are thinking of implementing 2 GB in the future, check into the current specs for 2GB support. You do not want to implement cable lengths today for 1GB FC that cannot be upgraded for use with 2GB equipment because the cable distances are too long. In general, the 2GB distances are approximately half the distance of 1GB distances. Pay particular attention to 9 micron, long wavelength runs, the supported 2GB distances might be less than a 25% of the supported 1GB distance.

As to copper, both certain varieties of coax and shielded twisted pair cables are supported. The ends are definitely not RJ-45. I don't think 2GB FC supports copper and severely doubt that higher speeds will support copper. So, why copper in the first place? Because it's cheaper than fiber optic cabling and it works. 1GB distances are supported to 25 meters. In general it looks like copper is falling by the wayside. It never did have a chance for FC, given that the technology is called FIBRE Channel.

Regards,
Marc Farley

Editor's note: Do you agree with this expert's response? If you have more to share, post it in our Storage Networking discussion forum at http://searchstorage.discussions.techtarget.com/WebX?replyToMessage@7.uALMagHuauI^1@.ee83ce4!viewtype=convdate

#### Have a question for an expert?

Get answers from a TechTarget expert on whatever's puzzling you.

You will be able to add details on the next page.

#### Start the conversation

Send me notifications when other members comment.

## SearchDisasterRecovery

• ### Zerto plays big role in McKesson's disaster recovery plan

McKesson Corporation's disaster recovery plan is deeply detailed and relies on Zerto's technology across its many globally ...

• ### Why you should have a disaster recovery testing plan in place

Regular testing of a disaster recovery plan is one of the only ways to ensure a plan is working, up to date and well-tailored to ...

• ### Post-disaster recovery, don't overlook user connectivity

After you've successfully recovered your environment, the job isn't quite over. Ensuring user connectivity following a recovery ...

## SearchDataBackup

• ### Create an effective data backup strategy from scratch

You can't reliably protect your organization's valuable data without having a solid data backup plan in place. Here's what to ...

• ### Druva expands on AWS backup, moves S3 snaps across regions

In response to customers' expanding AWS footprint, Druva added new backup features to CloudRanger, which it acquired in 2018 for ...

• ### SaaS backup services deliver data protection for SaaS apps

Providers of SaaS apps offer only basic data recovery protection. Learn which SaaS backup services and cloud-to-cloud data ...

## SearchConvergedInfrastructure

• ### HCI storage adoption rises as array sales slip

Dell goes against the grain by increasing storage sales, but much of its gains came from hyper-converged and data protection ...

• ### Microsoft Storage Spaces Direct simplifies converged, HCI storage

Storage Spaces Direct in Windows Server packages several different Microsoft technologies to lower TCO and simplify storage in ...

• ### Explore compelling benefits of hyper-converged infrastructure

Better support remote office/branch office environments and address budgetary, efficiency, scaling and operational challenges ...

Close