Ericsson MINI-LINK TN R3 ETSI, Technical Description

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Basic Node
3.7.2.1.1 TDM
This block interfaces the TDM bus by receiving and transmitting nxE1 (n
≤
96)
for aggregation. The transmitted E1s need synchronization input utilizing the
Network Synchronization mode.
3.7.2.1.2 IMA
This block implements the Inverse Multiplexing for ATM (IMA). The ATM cells
are broken up and transmitted across multiple IMA links, then reconstructed
back into the original ATM cell order at the destination.
3.7.2.1.3 ATM Cross-connectt
This block handles the ATM cross-connection of traffic on a maximum of 31
ATM interfaces. Each ATM interface corresponds to either an IMA group or
a G.804 link.
When setting up cross-connections, Connection Admission Control (CAC)
calculations are performed in order to accept or reject new connection requests
according to the available bandwidth.
The function of the ATM Cross-connect block can be summarized as:
• Policing
• VP/VC Cross-connection
• Buffering and Congestion Thresholds
• Scheduling and Shaping
Policing
The policing function is used to monitor the traffic flowing through a specific
connection in order to ensure that it conforms to the configured traffic
descriptor of the connection. It fully meets the relevant requirements and
recommendations from the ATM Forum Traffic Management and ITU-T I.371.
Policing is enabled by default for all the service categories and can be disabled
on a per-connection basis.
VP/VC Cross-connection
The different ATM interfaces can be cross-connected, mapping ingress
connections to egress connections and vice versa.
In a VP cross-connection only VPI numbers are associated between two ATM
interfaces. In a VC cross-connection the VPC is terminated and the ingress and
egress connections are associated using both VCI and VPI numbers.
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