Tom, [...]
> The trouble is, the value of a is related to the number of blocks by the > formula > > Number of blocks = 2^a > > The number of blocks determines how many port ranges are allocated to each > MAP CE (i.e. with system ports and hence the first block excluded, a = 4 > implies that each sharing MAP CE is allocated 15 separate ranges of ports). I > think you want to retain the operator's flexibility to allocate fewer blocks > or, in the interest of reducing the chance that an attacker can guess the > next port allocated, more blocks. Of course, the operators in the WG may > disagree. for the sake of simplicity I'd rather we made the offset fixed to 4, and that if one wants fine grained control of port ranges use something like PCP or DHCP. that said, you are suggesting a rule, that would say something like: if a > 6, then the 6 most significant bits of A MUST not me zero. e.g. with offset = 8, PSID length 4 xxxx xxXX PSID yyyy then only the 'x' field > 0. thereby only excluding 1024 ports, with large offset. cheers, Ole _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
