NIS χρήστης δεν κάνει logon στον Η/Υ

[V13]

On Tuesday 17 July 2007, Christos Ricudis wrote:
> Texnika den yparxei kammia diafora. Oi dyo syndesmologies einai apolytws
> isodynames, mono pou antistrefontai ta zeygh 2 (portokali zeygos) kai 3
> (prasino zeygos).

  Symfona me to wikipedia[1], ta 2 zeygaria exoyn diaforetikes antistaseis 
metaksy toys. Den ksero bebaia kata poso isxyei kati tetoio. Opos leei aloste 
kai ekei: 

"Mixing T568A-terminated patch cords with T568B-terminated horizontal cables 
(or the reverse) does not produce pinout problems in a facility. Although it 
may very slightly degrade signal quality, this effect is marginal and 
certainly no greater than that produced by mixing cable brands in-channel"

> An koitaksete to USOC protypo poy xrhsimopoieitai sthn thlefwnikh kalwdiwsh
> sthn amerikh, 8a deite oti ta dyo kentrika zeygh exoun akribws thn idia
> diataksh me to 568A.

  Apo ekei ksekinaei to thema

> Etsi, 8a mporousate sto patch panel sas, na parete to mple zeygos - pou
> akribws gi ayto to logo den xrhsimopoieitai apo to Ethernet - kai na to
> riksete panw sto thlefwniko sas kentro, wste na mporei h grammateas na
> bgazei ton ypologisth apo to mprizaki, na bazei to thlefwno sto idio
> mprizaki kai na antallasei syntages gia gioubarlakia me thn kouniada ths
> enw paizei pasientza, pou den apaitei th xrhsh diktyou.
>
> H diafora twra metaksy toy 568A kai tou 568B brisketai sto DEYTERO zeygos
> toy RJ11, pou mporei na metaferei mia deyterh thlefwnikh grammh sthn
> periptwsh ths thlefwnias. To 568A exei thn idia diataksh sto deytero zeygos
> me to USOC protypo. Ayto, kapoios pou epairne POLY lhgmena narkwtika,
> skefthke oti 8a htan kalh idea, alla kanenas allos meta apo ayton den
> katafere na brei akribws thn idia partida lhgmenwn narkwtikwn gia na
> diapistwsei GIATI tou fanhke kalh idea - apo th stigmh pou to zeygos ayto
> xrhsimopoieitai KAI sthn periptwsh tou Ethernet KAI sthn periptwsh ths
> deyterhs grammhs tou thlefwnou, einai apolytws adynaton na xrhsimopoihseis
> eite to ena eite to allo, ara den yparxei logos na kratas symbatothta.

  AFAIK h idea einai oti xrisimopoieis T568A se katakoryfi kalodiosi kai T568B 
se orizontia (symfona me ta protypa ton thlefvnadon, asxetos me to oti h 
plhroforiki den exei kamia sxesi me thlefonia... aytoi den to kseroyn). 
Exontas T568A sthn katakoryfi mporeis na xrhsimopoihseis to idio kalodio kai 
gia thlefoniki syndesh tesaron kalodion kratontas ton idio xromatiko kodika, 
oste na einai xaroymenoi oi thlefonades, xoris na xreiazetai na toys eksigeis 
oti tha mporoysan na xrisimopoihsoyn alla 2 zeygaria. Enalaktika, tha 
mporoyses na pernas tilefono apo ta 3-6, 4-5 zeygaria kai diktyo apo ta 1-2, 
7-8.

  To erotima poy tithetai einai to giati na mpei ston kopo opoios to ekane 
ayto na anaferei kai to T568B ? Isos h apantisi pragmati na sxetizetai me 
narkotika...

  Pera apo ta parapano, to 802.3 den einai mono to 10Base-T, to 100Base-TX kai 
to 1000Base-T. Exoyn ginei kai alles (polles) apopeires [3], oi opoies eginan 
standards ths IEEE kai oi opoies apla den 'epiasan'. Ayto synepagetai pos o 
arxikos sxediasmos ton kalodion mporei na min exei na kanei se tipota me to 
pos xrhsimopoioyntai shmera. To sigoyro einai pos h arxiki idea gia to 
Ethernet me Twisted Pair kalodio den miazei me to ti ginetai shmera. Se 
opoiadipote periptosi, ta T568A kai T568B einai asxeta me to ethernet [4][5]

> Christos Ricudis
<<V13>>

[1] http://en.wikipedia.org/wiki/T568B
[2] http://en.wikipedia.org/wiki/25-pair_color_code
[3] http://en.wikipedia.org/wiki/802.3
[4] http://www.nordx.com/public/htmfr/pdf/2050.pdf
[5] http://www.belden.com/pdfs/Techpprs/2050.pdf