Mpls Features; Figure 2 Atm Forwarding - Zte ZXR10 8900 Series User Manual

F 2 ATM F
IGURE ORWARDING
ATM switches forward packets through VPI/VCI. The switches do
not judge routing information when forwarding ATM cells.
When an ATM switch receives a packet, it looks up VPI/VCI table
and forwards the packets in switching way.
When forwarding packets, ATM switches have the following fea-
tures:
� ATM chooses the path on the base of data link layer. VPI/VCI is
effective for local switch. The fast looking-up is implemented
by hardware.
� ATM network is a connection-oriented network, so it can im-
plement QoS according to different VPIs/VCIs.
� ATM supports traffic control mechanism and different kinds of
services, such as real time service.

MPLS Features

MPLS belongs to the third generation of network architecture. It
is a new switching standard of IP high-speed backbone network,
brought forward by Internet Engineering Task Force (IETF).
MPLS uses simplified ATM switching technology to implement
switching in layer 2 and layer 3.
each IP message, and encapsulates the identifier to a new MPLS
message together with the IP message, deciding the transmission
path and priority of the IP message.
The differences between MPLS and traditional
are in the label distribution method and label stack introduced by
MPLS. In MPLS, the use of label stack brings new applications, such
as traffic engineering,
Before forwarding the IP packet according to corresponding path,
the MPLS router reads the header identifier of the message instead
of the IP address in each IP message. Therefore, the speed to
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Chapter 2 MPLS Configuration
It provides an identifier for
VPN and Fast Re-Routing (FRR).
WAN technology
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