This is relatively easy, compared to
Ethernet's
RJ-45 T568A/
T568B layouts. BUT there is a twist, you must flip the RJ11 connector on one end so that same-coloured wires line up when when the cables crimps are put end-to-end. The Black and Yellow wires are optional and may not be present.
________________ ________________
| | | |
----|-##---|=Black===| T2 |===Black=|---##-|----
| ## |=Red=====| R1 |=====Red=| ## |
| ## |=Green===| T1 |===Green=| ## |
----|-##---|=Yellow==| R2 |==Yellow=|---##-|----
|________________| |________________|
Viewed connector side, clip facing away
Using Cat-5 cable to make telephone cords
The key here is consistency. If all your cables,
keystone connectors,
hubs and
patch panels conform to
T568A/
T568B standards, then you can go ahead and use the Blue and Brown pairs, as they're not used by
Ethernet 10/100 baseT. Note that the Cat5 will be somewhat difficult to fit in an RJ-11 end, and you must clip off and discard Ethernet's Orange and Green
twisted pairs. Again, pair #2 aka Brown is optional.
________________ ________________
| | | |
----|-##---|=w/Brown=| T2 |=w/Brown=|---##-|----
| ## |=Blue====| R1 |====Blue=| ## |
| ## |=w/Blue==| T1 |==w/Blue=| ## |
----|-##---|=Brown===| R2 |===Brown=|---##-|----
|________________| |________________|
Viewed connector side, clip facing away
The full wiring details can be found
here, crimping techniques
there.