RJ45 and RJ48 question

Posted on 2004-10-28
Last Modified: 2008-03-03
We are about to switch ISPs and currently our ISP provides us with our CSU/DSU so we have purchased a new cisco 2611xm router with a WIC-1DSU-T1 card for our CSU/DSU.  Currently our ISP uses a cable with RJ45 connectors on both ends to go from thier box on the wall  to their CSU/DSU. We are switching to Bellsouth and they tell me their box/demark will have an RJ48 female jack.  I know that an RJ45 cable can plug into an RJ48 outlet with no problem (not visa versa though).  The WIC-1DSU-T1 CSU/DSU has a female RJ45 outlet on it.  My quesion is what kind of cable to I need to go from the new Bellsouth RJ48 to the WIC-1DSU-T1. According to

i need a RJ-45 to RJ-45 straight-through cable (provided by customer) but will this work since the Bellsouth demark is actually a RJ48?? and will the inouts be correct??
Question by:mikeleebrla
    LVL 9

    Accepted Solution

    Since the rj-48 in this scenario is pin'd the same as an rj-45 (using pins 1/2 and 4/5) you'll be fine.
    Just make sure you leave your current connection active till you have tested. On switch over day just try it and you can always switch back.
    LVL 25

    Author Comment

    Thanks,, that is what i thought but i just wanted to be sure

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