Http://unixboy.javaeye.com/blog/451671
Http://unixboy.javaeye.com/category/75180
RJ45 connector:
Used for Ethernet (Ethernet 10/100/1000 m UTP/STP Interface), commonly used in Category 5 unshielded twisted pair wires. RJ-45 is also used for other interfaces such as ISDN, pins are defined differently.
Listen 48 connector:
Used to connect T1, E1 serial lines, usually using shielded twisted pair wire; RJ-48 can also support pin3, pin6 Grounding Connection.
The RJ45 and listen 48 lines are in the same order, both from left to right are 87654321, but the signal definition is different:
RJ45:
10/100 m with 1/2/3/6 needles. m with all 8 needles.
Listen 48:
Generally used for RJ-48C and RJ-48S, with 1/2/4/5 needle.
CT1/PRI-CSU (RJ-48C) signals are defined as follows,
RJ-48C pin description
1 receive ring
2 receive tip
4 rings
5 tip
For t1/E1 trunk and digital voice port (RJ-48) pin1 Signal
1 RX + (input)
2 RX-(input)
3-
4 Tx + (output)
5 TX-(output)
6-
7-
8-
References:
E1 (2 m transmission link) and shdsl/HDSL/SDSL are the last mile of transmission technology.
Digital Data Network is a data transmission network that uses digital channels to transmit data signals. It is essentially a circuit switching network.
FR is a group switching network technology. Virtual circuits can be divided.
Yes
DDN, FR, and ATM are regarded as backbone networks. DDN node machines, fr switches, and ATM access switches are the most edge devices in their networks. From these devices to users
It uses the last mile transmission technologies such as E1, shdsl, HDSL, and SDSL. Because FR and ATM support PVC, channel-based access is not required for point-to-point access.
E1. For E1, the BNC interface is usually sent from the optical fiber to the user. Can be converted to interfaces of limit 48. The maximum speed is 2 Mbps, which is a time line. Also known as channelized E1.
There are two router Connection Methods:
1, with BNC-E1 cable (here E1 side includes: Listen 48, db15 and other forms of Interface) directly connected to the E1 Module
2, if the WIC-1T module is used, then a g.703 ----- V.35 protocol converter is used after v. 35 cables connected to the WIC---1T module.
Shdsl/HDSL/SDSL are all user data lines. Generally, one or two pairs of telephone lines are used to connect to the user. The interface is or 48. The maximum speed can reach 2 mb bps or higher. Although XDSL technology can reach a rate of 2 m, I have never heard of it yet that it can run channelized E1 on DSL lines.