Configuring Port Tunneling - Extreme Networks PoS Installation And User Manual

Configuring Port Tunneling

Configuring Port Tunneling
Port tunneling can be used to encapsulate and transport the raw High-Level Data Link
Control (HDLC) encapsulated byte stream from one PoS port to another PoS port across
an MPLS network. This allows service providers to tunnel different types of SONET
HDLC streams across a non-SONET backbone like Ethernet. The initial implementation
of port tunneling requires an MPLS backbone network.
The following ExtremeWare port command has been added to support HDLC tunneling
on a PoS module:
config ports <portlist> tunnel hdlc [off | mpls]
After you configure the PoS port, you can tunnel HDLC encapsulated frames from a
PoS port across a SONET or Ethernet based MPLS network. The ingress PoS port
encapsulates the entire HDLC frame, including the HDLC header and FCS, inside an
Ethernet/MPLS header. HDLC control bytes are de-stuffed on the ingress PoS port. The
egress PoS port strips the Ethernet/MPLS header and forwards the HDLC frame.
HDLC control bytes are stuffed on the egress PoS ports. HDLC idle bytes, x7E, are not
tunneled, but runts and aborted frames are tunneled. Figure 3-20 displays port
tunneling between PoS port 1:4 on BlackDiamond switch 1 and PoS port 8:4 on
BlackDiamond switch 2 with a PPP link between Customer switch 1 and Customer
switch 2. PPP is not terminated on either BlackDiamond switch 1 or BlackDiamond
switch 2.
Packet Over SONET Module Installation and User Guide 3-97