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

This was last published in November 2001

Content

Find more PRO+ content and other member only offers, here.

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.

SearchSolidStateStorage

• Hybrid and AFA storage array types battle for dominance

The debate still rages over whether all-flash arrays will make hybrid arrays obsolete, and cost is not all that matters when ...

• Storage tiers: SAS interface, MLC flash rising

SAS vs. SATA battle in enterprise data storage shows hard drives with SAS interface trending up; cheaper MLC SSDs outnumber SLC ...

SearchCloudStorage

• Cloud survey uncovers seven storage services trends

Latest TechTarget cloud survey finds cloud backup, cloud file sync and share, disaster recovery and archiving are most popular ...

• Survey finds cloud storage implementation growing but cautious

Cloud storage implementation by users ranges from backup and DR to tiering. We reveal the most-used cloud storage applications ...

Assistant Editor Rachel Kossman tweets links to our content, as well as analysis from industry experts. Interact with her, let us...

SearchDisasterRecovery

• Enhance your GRC program with business continuity and DR

Any governance, risk management and compliance program should work with an organization's business continuity process. There are ...

• Frost Science Museum IT DR planning braced for worst, survived Irma

The Frost Museum of Science on the water in Miami braced for Hurricane Irma with a solidified storage and data center ...

• Using virtualized disaster recovery to fight ransomware

When it comes to fighting and protecting against ransomware, there are some major features of virtual disaster recovery that top ...

SearchDataBackup

• The role of a GDPR data protection officer

The data protection officer, required for many organizations to be compliant with the EU's GDPR, will face challenges in the new ...

• Veeam acquisition of N2WS enhances cloud protection

Veeam will integrate N2WS technology into the Availability Platform. The companies' research and development teams will work ...

• Data backup and recovery software: 2017 Products of the Year finalists

The backup and disaster recovery software and services finalists include established vendors and newer entrants, offering a wide ...

Close