Section 5 of the latest version of MAP has the following:
1. Basic Mapping Rule (BMR) - mandatory, used for IPv4 prefix,
address or port set assignment. There can only be one Basic
Mapping Rule per End-user IPv6 prefix. The Basic Mapping Rule is
used to configure the MAP IPv6 address or prefix.
2. Forwarding Mapping Rule (FMR) - optional, used for forwarding.
The Basic Mapping Rule is also a Forwarding Mapping Rule. Each
Forwarding Mapping Rule will result in an entry in the Rules
table for the Rule IPv4 prefix.
Question: there will always be a BMR. In the absence of additional
rules, how does a CE know whether it can use the BMR for forwarding or
must always use the default rule?
Remark: I'm not sure these two bullets tell the full story as they
stand. I propose to modify them as follows:
1. Basic Mapping Rule (BMR) - mandatory. There can only be one
Basic Mapping Rule per End-user IPv6 prefix. In combination
with the End-user IPv6 prefix, the Basic Mapping Rule is used
to derive the IPv4 prefix, address, or shared address and
the PSID assigned to the CE.
2. Forwarding Mapping Rule (FMR) - optional, used for forwarding.
The Basic Mapping Rule is also a Forwarding Mapping Rule. Each
Forwarding Mapping Rule will result in an entry in the Rules
table for the Rule IPv4 prefix. Given a destination IPv4 address
and port within the MAP domain, a MAP node can use the matching
FMR to derive the MAP IPv6 address of the interface through
which that destination address-port combination can be reached.
Tom Taylor
_______________________________________________
Softwires mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/softwires
