RE: [802.21] [DNA] Prefix information for link identification in DNA
Hi Qiaobing,
> > Link up (link_X) indicates that link_X is available to
> carry data. Since the MIH users of this event are at IP layer
> and above, they would not have use of an indication stating
> that the UE has setup a L2 connection with a BSS or SGSN
> (since that is only signalling, not user plane). Link up in
> this case means that the UE has a usable PDP context with a
> GGSN and therefore has been assigned and IP address, so that
> the link can be used to carry data.
> ...
>
> So, your "link_up" here means the IP connectivity is up and ready. In
> other words, your "link" here refers to the IP link used in
> DNA, instead
> of a L2 link. Do you think in general 802.21 link events should be
> defined for IP link?
No, not necessarily. For Link Events, Link-up should be related just to L2 link. My point is that just having the link layer up does not mean that any IP traffic can be exchanged. Therefore, a Link Event Link-up received by the MIH should not be interpreted as the fact that MIH needs to send an MIH Event Link-up to the MIH User. the MIH event toward the MIH user indicating that the link is up in some cases needs to just indicate that the L2 is up (e.g. for MIH user being MIP), in other cases it needs to indicate that the link is ready to exchange IP traffic.