User guide

Packet Over SONET Module Installation and User Guide 3-25
Configuring and Monitoring PPP Functions
Figure 3-7: View of logical connectivity to PoS ports with BCP enabled
As Figure 3-7 shows, PoS ports 1 and 3 are bridged together along with Ethernet port 1
to form VLAN x, PoS port 3 belongs to both VLAN x and VLAN y, and routed
connectivity exists between VLAN x and VLAN y.
BCP is defined in RFC 2878, which was recently approved by the IETF as an update to
RFC 1638. Two features of the updated version are: support for IEEE 802.1Q VLANs,
and inline management. The VLAN support enables a BCP entity to advertise its ability
to accept frames containing a VLAN tag. Inline management refers to the capability of
transporting the Spanning Tree Protocol and other bridge management protocols inline
using the Bridged Data PPP Protocol ID (previously, RFC 1638 specified that Spanning
Tree Protocol messages be transported using a unique PPP Protocol ID). Extreme’s
implementation supports these features as specified in the new RFC.
MultiProtocol Label Switching Control Protocol. MPLSCP establishes and
configures a connection for transporting MPLS labeled frames across a PPP link. The
MPLSCP connection must be established successfully before data traffic can flow over
the link. Only unicast MPLS labeled packets are supported. Multicast MPLS labeled
packets are discarded by the PoS port.
1234AB5678
PoS_022
192.168.10.1192.168.9.1
VLAN y
PoS
port 1
PPP-BCP
PoS
port n
PPP-BCP
VLAN x
Ethernet
port 1
IP Router
PoS
port 3
PPP-BCP