Hi Alper,
It seems like this whole document is related to IEEE 802.21 D.01 standard on Media Independent Handover (MIH). Link Up and Link Down are among the Link Events defined in 802.21 which are part of the Event Services (ES). 802.21 also treats mappings from individual link layers like 802.11, 3GPP, etc. like you have it in your draft.
My question is if you have any new message that 802.21 does not have?
My suggestion is at least to reference this document.
Regards,
Behcet