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Cat 6 over long distance

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nickoedwards

IS-IT--Management
Jun 10, 2007
16
GB
Hi,

I have a technical issue with a side question. Basically we have 2 warehouses and are circa 90m apart in a residential area. At the moment we're running a VPN between the 2 but its not proving reliable / fast enough.

We've looked at optic fibre but as you can imagine we going to have to run a cable over some residential roofs etc. Long story short we'd thought we'd try Cat6 first. Although the warehouses are 90m, switch to switch will exceed 100m.

I know over 100m is not recommended but to have to the best chances of succeeding i'm looking for advice. We have 2 Dell Powerconnect 3248's (we're on a budget and bought them off ebay).

Would it literally be a case of plugging in the cable to each one and hoping it connects? Would you add a repeater in the mixer or would straight switch to switch be powerful enough?

Thanks in advance. Nick.
 
Switch to switch with a crossover. Definitely worth a try.

Adversity is Opportunity
 
Cat6 outside aerial, Is that a legal installation? Cat6 is not designed for this type of installation..If you are going to run a cable between buildings via aerial I would run a 6 or 12 strand fiber cable.

Signature===========================================
Artificial Intelligence Is No Match for Natural Stupidity.

The latest survey shows that 3 out of 4 people make up 75% of the population.

The original point and click interface was a Smith & Wesson.

Red meat is not bad for you, it is the green fuzzy meat that is bad.
 
In addition to the outside requirements of the cable to survive the elements, there are NEC requirements that MUST be followed!

What area is this installation located?

Draping cable over roofs in a neighborhood in not Code anywhere in the USA.

....JIM....
 
I understand CAT6 isn't designed for this but as a low cost option i thought it would be worth a shot.

It is a legal installation, perhaps the way i described it was a little slap dash. We're going to be following the same route as the residential telephone cables (with permission).

In response to Deweyhumbolt's reply, i didn't think of using a crossover cable. Could you use a straight through? The only reason i ask is because we've already purchased the cable but i could easily convert it to crossover.
 
Crossover is only required if your switch won't do it for you.

Be SURE to put appropriate PRIMARY lightning protection on this cable - not only for equipment safety, but for human safety (can you say liability?)

Also - some switches will run signal farther than others. If it doesn't work immediately, try a different switch at each of the ends.

Finally, fiber is really the right solution here. The cost isn't much more and you have no lightning/distance issues. I know that you've already bought the cable, making this a moot comment. And I suspect that copper will work just fine for years, assuming that you've bought the appropriate aerial cable (didn't know there was aerial cat6, but who knows...)
Good luck
Mike
 
All entrance cable MUST be protected at the point of entrance into a building. This is NEC code and you may have trouble running through these protectors. You must terminate the cable on some sore of primary protection device or you will be liable for anyone getting hurt by voltage surges such as lightning and electrical shorts.

Signature===========================================
Artificial Intelligence Is No Match for Natural Stupidity.

The latest survey shows that 3 out of 4 people make up 75% of the population.

The original point and click interface was a Smith & Wesson.

Red meat is not bad for you, it is the green fuzzy meat that is bad.
 
The Dell switches will do the auto cross. The length being slightly over a 100M is not the ideal situation, but it should work.

I would look into surge protection for the cable on each end though, it could save some severe headaches in the near future.
 
Your best bet would to go with 50 micron Fiber,using the outdoor type,to wall mount fiber panels near the 'head in',ground the panels, and then run fiber to the switches.

Good Luck,

Has been in the cabling business for about twenty years and is now the Sr PM for a cabling company located in the Los Angeles area.
Also a General Class Amatuer Radio Operator.
 
By the time you but the cable, Cat 6 protectors (if they make any), have someone install this. You have just spent that money on something thats still iffy and can still take a lightening hit. When you could spend just a little more (or about the same) and put fiber in and be done with it. The connections between then could be gigabit (not a iffy 100 MHZ.)

IMO that would be the best you could do for your company and not have to worry about lightening taking our a couple of switches. Oh did I mention that OSP fiber is very easy to come by and doesn't require protection units?


"A people that values its privileges above its principles soon loses both."
- Dwight D. Eisenhower (1890-1969), Inaugural Address, January 20, 1953

For the best response to a question, read faq690-6594


 
Thanks for your advice guys, we've completed the installation and thought i'd update you so that others having similar experiences in the future can learn from it... not that there's much to learn!

Basically, I kept the cable as a straight through and installed the cable. I'm estimating that its circa 130 metres in length, may be more. The hardest part was laying it securly and neatly. Now that it's down, there's a massive difference in performance.

I'm now going to look at surge protections - can anyone make any recommendations?

As an added questions, in each warehouse there is a broadband connection for the original VPN. We're going to keep them as a back up, but, is there anyway to configure the system to use them both... in a load balancing manor? Or is me being over the top?

Nick.
 
Oneac makes some very good protectors.

Signature===========================================
Artificial Intelligence Is No Match for Natural Stupidity.

The latest survey shows that 3 out of 4 people make up 75% of the population.

The original point and click interface was a Smith & Wesson.

Red meat is not bad for you, it is the green fuzzy meat that is bad.
 
You could maybe get some routers that would use the cat6 for site to site and the broadband for internet.

Kevin Wing
ACA- Implement IP Office
Carousel Industries
 
I believe ITW Linx makes a CAT6 rated protector. Don't forget proper bonding/grounding practices!

....JIM....
 
Great call SYQUEST

You may have electrical grounding float between these 2 buildings. If one is higher, some (all?) grounds will try to flow to the other. A real nasty bugger if you have a lightning strike, electrical motor burnout mishap or bad electrical plug grounding.

Water may also be an issue. PVC jacket cable holds up a little better than plenum in water.

Are the designated cable paths in your building plenum rated? If so you may be in Fire Code violation with PVC cable. It is even worse with sticky-pic (water block) cable.

Remember, BICSI & EIA/TIA are recommended (yes I said it) installation practices. Fire Code compliance is mandatory. Always err on the side of human safety.

I just stepped off my soap box.

Regards
Peter Buitenhek
ProfitDeveloper.com
 
After reading all the posts it seems fibre would be a better option as there now might be a possibility to lay it under ground.

If we were to go down the fibre route and remove the CAT 6 can you recommend any budget fibre switches?
 
Buy two media converters - fiber to copper - and keep your existing switches. They should land around $200 each for OK units.
Mike
 
depending on your switches that you have from dell, they have SFP modules where you can get LC connections for the fiber to plug right in to the switch with out having to buy the conversion boxes

------------------------------------
Dallas, Texas
Telecommunications Tech
CCVP, CCNA, Net+

CCNP in the works
 
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