Evaluation of Physical Carrier Sense Based Backbone Maintenance in Mobile Ad Hoc Networks

Table 1

Summary of slot lengths and information exchanged.

Phase	Slot	Message vulnerable to collision	Exchanged information (bits/msg)	Message length (bytes)
I	1	No	1	6
	2	No∗	1 or 48∗	12
	3‡	No	1	6
II	1	No∗	1 or 64∗	14
	2	No	1	6
	3	No	1	6
	4	No	1	6
III	1	Yes	96 or 1†	18
	2	No	50 or 98	18
	3	Yes	112	20
	4	No	208⋅12	6+26⋅12

∗Phase I slot 2 and Phase II slot 1 can be used to collect information in advance for Phase III, provided the messages do not collide. When this mechanism is used in simulation, the larger number of information bits is recorded. ‡Phase I slot 3 is the self-stabilization slot. †In Phase III slot 1, active leader nodes may only sense a busy or free carrier when the number of ordinary nodes transmitting is not equal to one. This carrier sensing determines the leaders reply type in the next slot.