Network Interfaces; Basic Rate Interface Bri-T - Aastra 470 System Manual

Installation
4. 7. 2

Network Interfaces

Equipping the system with interface cards provides the necessary network inter-
faces. With the exception of the Ethernet interface, which also represents a network
interface via SIP access, there are no network interfaces on the Aastra 470 commu-
nication server.
4. 7. 2. 1

Basic rate interface BRI-T

Fitting BRI interface cards means that BRI network interfaces are available on the
RJ45-sockets on the front panel of the cards. The possible RJ45 sockets are high-
lighted in colour in the figure below.
Fig. 35 Connection possibilities for BRI network interfaces
Notes
– The interfaces of sockets 1 to 4 can be switched to BRI-S. The interfaces
of sockets 5 to 8 are permanently configured to BRI-T.
– Circuit type as per EN/IEC 60950: SELV
The connection from the front panel to the NT1 (Network Termination) is via stand-
ard commercial straight patch cables with 8-pin RJ45 connectors on both sides.
With the appropriate tools you can also create your own cables.
Cable Requirements
Tab. 42 Cable requirements for basic rate interface BRI-T
Core pairs × cores
Stranded
Wire diameter, core
Screening
Characteristic impedance
Wave attenuation
Near / crosstalk attenuation
100
1 × 4 or 2 × 2
yes
0.4...0.6 mm
recommended
< 125 Ω (100 kHz), < 115 Ω (1 MHz)
< 6 dB/km (100 kHz), < 26 dB/km (1 MHz)
> 54 dB/100 m (1 kHz to 1 MHz)
Aastra 470 as of R1.2
syd-0337/1.2 – R1.2 – 11.2011