Selta Alyseo 106, Руководство пользователя

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Alyseo 106

SELTA S.p.A
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2-2 Overview
Alyseo 106 User Manual
720041008-A0-GB Issue 4
2.2.2 SHDSL Port
The physical connection can be configured as reported in chapter 4. Typically, these parameters
are set by the service provider and must not be changed. When DSLAM, on central side, manages
the configuration of some parameters through the EOC channel, the parameters set by the user
are overwritten. Through the same EOC channel, it is possible to monitor the status of the remote
terminal from the exchange side in terms of Noise Margin, attenuation and line and to display
information about the type and the version of the connected terminal.
In case of dedicated connection between two Alyseo devices, one device must be programmed as
CP and the other as CO and all the other parameters can be selected by the user.
Enabling the Power Backoff automatically reduces the power transmitted on line over the network
port, if a line attenuation lower than a predefined threshold is automatically detected, with the
purpose to reduce the crosstalk effect in the cable. In any case, the device performances are not
reduced.
2.2.3 ATM Termination
The Alyseo 106 terminal, in the interworking applications between ATM networks and Frame
Relay, is a device that realizes the access to the ATM transport network, implementing an ATM
user interface, according to ATM Forum normative UNI 3.1 and 4.0. The device supports up to 100
contemporaneous ATM connections of PVC type (+1 for remote control). The connections can be
configured in independent way.
The service class of UBR, UBR+, VBR-rt and CBR type are supported, whose following
parameters can be configured:
Service class Priority Maximum band Minimum ensured band Ensured Burst
CBR 0 PCR PCR -
VBR-rt 1 PCR SCR MBS (to PCR)
UBR+ 2 PCR MCR -
UBR 2 PCR - -
The diagnostics at ATM level is realized by means of the management of the OAM signalling with
particular reference to F4 and F5 flows of AIS, RDI and loopback type, in compliance with the ITU-
T I.610 normative. Both ‘end to end’ and ‘segment’ types of stream are supported.
The ATM connections on the SHDSL interfaces are subjected to static Connection Admission
Control (CAC), whose maximum available band must be defined according to the following
formula:
and AvailableB MCR PCR PCR
i UBR VBRi CBRi
≤






+ +
∑ ∑ ∑
+
The available band can be configured between 0 and 2304 kbit/s (maximum DSL band) for the
IWF modality and between 0 and 1920 kbit/s (maximum available band on E1 interface foreseen
by G.804) for the CF modality.
The CAC can be disabled by the user.