MPLS DiffServ

• Network is a single DiffServ Domain

• ip2mpls Copy DSCP to EXP

• mpls2mpls Copy EXP Upward and Downward

• mpls2ip Copy EXP into the DSCP

• Uniform changes the markings.

Short-Pipe

• Customer network is a different DiffServ Domain
• ip2mpls # Maybe copy
• Copy top EXP into lower labels.
• Use the exposed DSCP when there is no label.
• When mpls2ip is done, act on the ip information not the prior EXP bits.

Pipe Mode (Multiple DiffServ Domains, Default, No Change To CE Marking)

• ip2mpls # Maybe copy DSCP to EXP.
• SP MPLS exp may be remarked in transit
• IPv4 is not remarked at egress
• Customer marking is unchanged.
• mpls2ip operation is based on what the prior MPLS EXP tag was.
• Must shut off PHP

References

RFC 3270: Multi-Protocol Label Switching (MPLS) Support of Differentiated Services | RFC Editor