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Net2WG 20061019 Meeting Note


*Link Layer Abstraction
*Testing CTP


Phil (P), Rodrigo (R), Om (A), Arsalan (A), Sukun (S), Note: Sukun


A: Last week, I sent out the first draft of link layer abstraction. It mentions requirements we discussed here: policy manager, etc.

P: Concern is that it is complicated, which is true for SP, too.

(Discussion about timing)

A: ‘next’ knows time when a specific neighbor will be awake: power duty cycle of the neighbor.

P: In low power listening, what is time off?

A: I don’t have a good answer.

P: The link with long preamble.

O: In low power listening, you don’t know.

P: Preamble?

O: It is the maximum.

P: (talk about Colorado’s MAC)

P: It still makes sense in LPL case. One of the point in SP is that flexible power scheduling can tell when the node will be on. Network layer tells the data link layer, you will be on this time specifying schedule.

O: FPS and LPL may not go together well.

P: FPS assumes CSMA MAC.

P: It is a shared data structure. How do you store series? Where all theses are stored and regenerated?

R: Would LPL be affected by network layer? They should be compatible.

O: FPS and LPL are up to their own schedule.

P: Does network protocol or link layer schedule? That is a question.

P: 40 packets for 40 nodes, which node will be in pull entry first?

A: LPL and FPS work together may not make sense in some cases. Scheduling is not compatible.

R: Let’s think of an example, where both will work together.

A: In FPS, what is other possible network protocol which turns on and off the radio?

P: It is reasonable to say once we get an implementation working, we can figure it out.

P: How FPS works over TDMA?

(Discussion about TDMA)

A: Is there no use for providing schedule information to and from the link layer?

P: Writing information part.

A: Anyone who wants to send to a node, knows when the node listens.

P: If a node is not intending to listen, how listening will work?

A: LPL maintain which neighbor will be up when?

P: Generally not the case.

O: In TDMA case.

A: I see the first version working well with LPL from moteiv. It is geared for 802.15.4.

A: What kind of work needs to be done by the next week?

P: You can decide which is important and goes in.

A: No meeting next week? I will go over the document, look at it. Any comments are welcome.

(Discussion about CTP testing)

P: In addition to RSSI map, Noise map is also useful.

O: Is there a program?

P: If you send me a RSSI map, I can generate it. Code freeze is the next week.

R: I can do testing.

P: Low power CC2420 MAC is coming. Once I drop it in, we can test it.