Encapsulation Methods for Transport of Asynchronous Transfer Mode (ATM) over MPLS Networks
draft-ietf-pwe3-atm-encap-11

> defined in [RFC4446], but the ATM PW specific interface paramenter is

Typo.

Includes the RFC2119 boilerplate but doesn't cite RFC2119.

Section 2., paragraph 1:

>    Packet Switched Networks (PSNs) have the potential to reduce the
>    complexity of a service providers infrastructure by allowing
>    virtually any existing digital service to be supported over a single
>    networking infrastructure. The benefit of this model to a service
>    provider is threefold:

        NIT: s/providers/provider's/


Section 4., paragraph 1:

>    One-to-one mode: The One-to-one mode specifies an encapsulation
>    method which maps one ATM Virtual Channel Connection ( VCC ) (or one
>    ATM Virtual Path Connection (VPC) ) to one pseudowire.

        NIT: Spaces before/after parentheses are unusual.
        (Elsewhere in the draft, too.)


Section 4., paragraph 2:

>    N-to-one mode (N >= 1): The N-to-one mode specifies an encapsulation
>    method which maps one or more ATM VCCs (or one or more ATM VPCs) to
>    one pseudowire.

        N > 1? Otherwise, wouldn't it be the one-to-one case? (Elsewhere
        in the document, too.)


Section 5.1.1., paragraph 10:

>    The sequence number space is a 16 bit, unsigned circular space. The
>    sequence number value 0 is used to indicate that the sequence number
>    check alghorithm is not used.

        NIT: s/alghorithm/algorithm/


Section 5.2., paragraph 1:

>    The network MUST be configured with an MTU that is sufficient to
>    transport the largest encapsulation frames. If MPLS is used as the
>    tunneling protocol, for example, this is likely to be 12 or more
>    bytes greater than the largest frame size. Other tunneling protocols
>    may have longer headers and require larger MTUs. If the ingress
>    router determines that an encapsulated layer 2 PDU exceeds the MTU of
>    the tunnel through which it must be sent, the PDU MUST be dropped. If
>    an egress router receives an encapsulated layer 2 PDU whose payload
>    length (i.e., the length of the PDU itself without any of the
>    encapsulation headers), exceeds the MTU of the destination layer 2
>    interface, the PDU MUST be dropped.

        Problematic to have a MUST on a configuration requirement in the
        first sentence.


Section 5.4., paragraph 1:

>    The setting of the TTL value in the PW label is application
>    dependent,

        NIT: There seems to be some text missing after the comma?


Section 6.3., paragraph 4:

>    The limitations of the AAL5 SDU encapsulation are:
>         -i. If an ATM OAM cell is received at the ingress PE, it is sent
>             before the cells of the surrounding AAL5 frame. Therefore,
>             OAM cell reordering may occur, which may cause certain ATM
>             OAM performance monitoring and ATM  security applications to
>             operate incorrectly.
>        -ii. If the ALL5 PDU is scrambled using ATM security standards, a
>             PE will not be able to exctract the ALL5 SDU and therefore
>             the whole PDU will be dropped.

        NIT: s/exctract/extract/

Several acronyms are not written out on their first usage:
 SVCs SVPs, SPVCs and SPVPs

  Section 17: s/then a native ATM service/than a native ATM service/

Per discussions with the authors of this draft and MPLS ping I would
strongly prefer that the discussion of TTL explicitly mention that TTL
0 cannot be used.