Atm Architecture - HPE FlexNetwork MSR series Configuration Manual

Figure 41 ATM switching
Router A
ATM2/4/1
PVC 0/100
GE1/0/1

ATM architecture

ATM has a three-dimensional architecture. It contains the user plane, control plane, and
management plane.
Both the user plane and the control plane are divided into the following layers: physical layer, ATM
layer, ATM Adaptation Layer (AAL), and upper layer. Each layer is further divided into sublayers.
The control plane establishes and tears down connections with signaling protocols. The
management plane contains layer management and plane management. Layer management
manages the layers in each plane and has a layered structure corresponding to other planes. Plane
management manages the system and the communications between different planes.
Figure 42 shows the relationships between layers and planes in ATM.
Figure 42 ATM architecture
Control plane
Upper layer protocol
ATM layers have the following functions:
•
Physical layer—Provides transmission channels for ATM cells. At this layer, cells received
from the ATM layer are transferred into a continuous bit stream after transmission overheads
are added to them. Meanwhile, continuous bit streams received from physical media are
restored to cells, which are then passed to the ATM layer.
ATM switch B
ATM2/4/1
PVC 0/100
In
Port VPI/VCI
ATM2/4/1 0/100
Management plane
User plane
Upper layer protocol
ATM adaptation layer
ATM layer
Physical layer
ATM2/4/2 ATM2/4/1
PVC 2/101 PVC 2/101
Out
Port VPI/VCI
ATM2/4/2 2/101
124
Router C
GE1/0/1