PRELIMINARY
Ethernet Functions
An example of EVPL is shown in Figure 10.
Metro
Ethernet
Network
Customer
Edge
Customer
Edge
12533
Figure 10 EVPL Service
It is possible to have multiple active EVPL services. The number is limited
to 16 EVCs per packet radio. The different Ethernet services can be routed
in different directions in the network.
Customer and service provider must agree on the mapping of different
C-VLANs into the different EVCs. The mapping of C-VLAN to EVC can be
one to one or many to one. Frames that arrive at the UNI with C-VLAN ID not
recognized by the service provider will be dropped at the UNI. The following
functions are supported to implement EVPL:
• Basic error checking of the Ethernet frames is performed (for example,
checking FCS, wrong Ethernet format, undersized packets or oversized
packets).
•
Rate limiting is used to police the ingress Ethernet traffic from the
different subscribers to make it possible to meet the agreed Service Level
Agreements (SLA).
• Drop non-conforming traffic or remark them with lower priority.
• Priority is used to make it possible for high priority packets to bypass low
priority packets in the buffers.
4.3.4 Ethernet Private LAN
An EPLAN provides LAN-type connectivity between multiple subscriber sites
through dedicated UNIs. An EPLAN service is shown in
Figure 11.
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1/22102-HRA 901 17/9 Uen PU1 | 2016-07-04
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