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medbuyer
join:2003-11-20
Memphis, TN

medbuyer to NormanS

Member

to NormanS

Re: DSL filter at Dmarc?

said by NormanS:

A 45 foot run on the premises is just 1% of the total of a 4,500 foot loop. Cat 5 would not be, "necessary", but you can probably get 60 feet for a reasonable price.

4500 foot loop? can you explain to me where you got this?

I thought cat5e runs were at a max of 300ft? Anything beyond that may need repeaters...

»wiki.answers.com/Q/What_ ··· 5e_cable

cat5e is cheap and the standard now...why get anything below it?

graysonf
MVM
join:1999-07-16
Fort Lauderdale, FL

graysonf

MVM


A 4500 foot loop might be considered a typical average for a copper loop run between a home and a CO.

The supposed 300 foot limit for CAT5 is from the ethernet specification. It does not apply to telephone service or DSL run over twisted pairs.

NormanS
I gave her time to steal my mind away
MVM
join:2001-02-14
San Jose, CA
TP-Link TD-8616
Asus RT-AC66U B1
Netgear FR114P

NormanS to medbuyer

MVM

to medbuyer
Arbitrary figure based on your stated distance between your demarc (NID) and your wall jack where the modem will be located. Made an easy mental calculation of percentage; sans "fence post consideration".

Cat 5e is a cabling standard, regarding twist rate needed for noise rejection to comply with the Ethernet standard for up to Gig Ethernet. But your telephone company is not using Ethernet between the CO/RT and the premises; nor even between the NID and any wall jacks. The premises wiring is an insignificant portion of the overall loop length between the DSLAM and the modem.

When I first got DSL service, there was approximately 35 feet of quad station wire (red-green/yellow-black) between the demarc (old-fashioned station protector; no NID) and the jack. And a 75 foot drop from the pole to the demarc. No standard for rate of twist in either. And no telling if there was any twist in the F1/F2 spans back to the CO; 9,156 feet by MLT(?) test. You could probably get away with using bell wire between your demarc and your wall jack.

My premises wiring was an ugly patchwork of quad station wire mixing daisy chain and star topology. 70's and 80's telephone wiring standards were to use either two-pair, or three-pair Cat 3 wiring, so I bought a spool of two-pair Cat 3 wire and rewired the premises. Cat 3 rating is only good for Ethernet up to 10 mb/s; but, again, premises telephone wiring is not Ethernet. BTW, even with splitter, and home run of twisted pair (Cat 3) wiring, I did not show a significant improvement over the "no-twist" premises wiring. I might gain a bit by separating the DSL line and voice line (used blue for voice and orange for DSL), but can't go back and and DiY it (chronic axonal demyelination of leg motor nerves), and don't want to pay for what would likely be a marginal gain. It is certain that rewiring the premises will not raise my ADSL sync from the estimated 5200 kb/s max to the near 7000 kb/s max needed to assure a 6016 sync for the AT&T 6M tier. ADSL2+ did not buy much more room; AT&T will still only build a 3M profile for that 9,156 foot loop.

Certainly Cat 5e is cheap enough, now. But you don't have Ethernet until you reach the LAN port(s) of the RG (modem).
medbuyer
join:2003-11-20
Memphis, TN

medbuyer

Member

said by graysonf:

A 4500 foot loop might be considered a typical average for a copper loop run between a home and a CO.

The supposed 300 foot limit for CAT5 is from the ethernet specification. It does not apply to telephone service or DSL run over twisted pairs.

ok...so, dsl signal from the NID to his modem using cat5e for example...what's the max length for that then?

I understood that ethernet over cat5e should not exceed 300ft....meaning from modem to whatever he wants to connect inside his offic on a wired connection.

graysonf
MVM
join:1999-07-16
Fort Lauderdale, FL

graysonf

MVM

The introduction of any reasonable amount of CAT5 cable between a NID and a modem will make no difference.

You would have to be at or near the limit of being able to obtain DSL service in the first place for this to matter. If this was the case, then using an entire 1000 foot spool of CAT5 might be enough to push your electrical distance back to the CO beyond an acceptable amount.