Hi Larry, Thanks fo your thorough review. See my comments inline.
Marc > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Larry Kreeger (kreeger) > Sent: Tuesday, October 30, 2012 1:55 AM > To: [email protected] > Subject: [nvo3] Comments on draft-bl-nvo3-dataplane-requirements-02 > > Hello draft-bl-nvo3-dataplane-requirements authors, > > I was reviewing this latest 02 draft fully with a special > focus on all the "MUST" statements and have the following comments: > > 1) In Section 3.2.1 it says: > "An L2 VNI MUST provide an emulated Ethernet multipoint > service as if Tenant Systems are interconnected by an 802.1Q > LAN over a set of NVO3 tunnels." > > Does this mean that the inner Ethernet frame must carry an 802.1Q tag? > Maybe it can be reworded to make it clearer by explicitly > saying something about VLAN tags. [ml] How about "An L2 VNI MUST provide an emulated Ethernet multipoint service as if Tenant Systems are interconnected by an bridge over a set of NVO3 tunnels. The bridge may be 802.1Q VLAN enabled."? > > > 2) In Section 3.2.1 it says: > "Loop avoidance capability MUST be provided." > > What does loop avoidance mean in the data plane? Is split > horizon forwarding enough? Is this implying that a TTL is > needed in the encapsulation header (inside the outer IP header)? [ml] No assumption is made. Either mechanism is applicable. > > 3) In Section 3.2.1 it says: > "As frames arrive from VAPs or from overlay tunnels, the MAC > learning procedures described in IEEE 802.1Q are used:..." > > Is there a more specific reference to a part of 802.1Q that > describes inner source MAC address to outer source address > learning? It may confuse readers because this draft refers to > inner MAC to outer L3 address. Is the reference to 802.1Q required? [ml] How about, "..., standard MAC learning procedures are used:"? > > > 4) In Section 3.2.1 it says: > "Broadcast, Unknown Unicast and Multicast (BUM) traffic > handling MUST be supported." > > It may be desirable for an operator to have the ability to > disable unknown unicast (if there is a control plane to > distribute MAC to L3 tunnel mappings), and also to disable > multicast if it is a service that they do not want to support. > Are you saying that an implementation must always forward > unknown unicast and multicast, or that it must be "capable" > of forwarding them if desired? It is the latter. The text will be clarified in the next revision. > > > 5) In Section 3.2.1 it says: > "To achieve this, the NVE MUST support ingress replication > and MAY support multicast over an overlay multicast tree." > > I don't see why ingress replication is a MUST if the underlay > can support multicast. I think this should be reworded to be > "To achieve this, the NVE MUST either support ingress > replication or MUST support multicast across the underlay > network if the underlay supports it." [ml] Agreed. The text will be changed accordingly. > > 6) In Section 3.3.2 it says: > "From an encapsulation perspective the IPv4 and IPv6 > encapsulations MUST be supported, MPLS tunneling MAY be supported." > > Requiring support for BOTH IPv4 and IPv6 seems too strong. > Can this be changed to "MUST support IPv4 or IPv6 and should > support both, MPLS tunneling MAY be supported." [ml] Agreed. > > 7) In Section 3.3.2.1 : > Is this mandating a specific entropy field in the > encapsulation header, or would using the source UDP port or > the GRE key qualify? If they would qualify, it would be good > to add a sentence to say so. Both are applicable. The text will be changed to reflect this. > > 8)In Section 3.3.2.3 it says: > "L2 NVEs MUST support ingress replication and SHOULD support > point-to-multipoint tunnels." > Must seems strong for ingress replication. There should be a > MUST support ingress replication or point-to-multipoint > tunnels. Also, this is inconsistent with section 3.2.1 where > p2mp tunnels are not mentioned but instead mentions an > overlay multicast tree. Does a multicast tree qualify as a > p2mp tunnel ? [ml] Correct, it MUST support either ingress replication or multicast (e.g. IP multicast trees or p2mp tunnels). The text will be changed accordingly. > > 9) General comment: In a few places there are instances of > "must" and "may" that are not capitalized. This will be fixed. > > Thanks, Larry > > _______________________________________________ > nvo3 mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/nvo3 > _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
