I reviewed this document for tsvart with a focus on issues related to the transport area. The document defines BGP extensions to enable service providers to deploy inter domain services based on different types of tunnels with MPLS used as an example. The objective of the document is to provide different types of services using these tunnels. 

From the viewpoint of the transport area, there are two important points that need to be discussed when considering such tunnels: 
- MTU problems if the tunnel configurations differ
- DSCP issues if DSPC is used to provide non-best effort services

These two issues are not discussed in the document. This could be a design choice, but then I would suggest to explicitly document it. For the MTU problem, it could be useful to mention that operators should coordinate the MTU of the tunnels used to prevent PATHMTU discovery problems that could appear in deployments. 

For the DSCP issue, it is unclear from the document whether DSCP will be used. The document 
specifies that different operators could use different BGP codepoints and that these codepoints could be mapped from one operator to another, but there is not discussion about the same problem for DSCP in the data plane. RFC5462 defines E-LSPs and L-LSPs, but it is unclear from the draft whether any of these types of LSPs are used. This should be discussed in the paper as this will have an impact for some deployments.