Hello everyone, I have problem with understading of cable type of Telco.
In Cisco book (ICND 1,100-105) talks about Leased-Line Cabling. And book says that:
......The serial cable connects to the router serial interface to the external CSU/DSU. "The four-wire cable from the telco plugs in to the CSU/DSU, typically using RJ-48 connector that has the same size and shape as an RJ-45 connector."
Please tell me , four-wire cable comes to customer from TELCO? Is it genius. Customer just use only 4 wire cable?
Is it right? Or instead which type of cable comes from Telco to customers, I was thinking that it is serial, but serial is using only for between CSU/DSU and Router?
And my second question is what is data port that is a big one?. Look at this pic pls.
