Dear Jonathan, thanks for your comments. See inline our responses:
2016-12-12 22:48 GMT+01:00 Jonathan Simon <[email protected]>: > Xavi, Kris - Some questions about draft 17: > > 4: The callouts in figure 1 don't exactly match what's in 4.5.2, namely > that the timelsot and hopping template IDs (as opposed to the full > sequence) are what is carried in the EB. > > XV: The proposed configuration as advertised in the EB uses the default timeslot and hopping template ID. macTimeslotTemplateId = 0 and the default (macHoppingSequenceID = 0). Following your suggestion I will change the table to indicate this (macHoppingSequenceID = 0). Should we also keep the default sequence as a clarification (indicating that) [5, 6, 12, 7, 15, 4, 14, 11, 8, 0, 1, 2, 13, 3, 9, 10]? > 4.5: This paragraph could be interpreted as saying that a compliant node > may choose particular settings, but must be able to understand all possible > valid TSCH settings to be 6TiSCH compliant. I don't understand that you > "may" set to any valid TSCH setting but you "should" set them to what is > specified later on. > > XV: You are right. We need to clarify this. I think we want to be clear > here with the recommended frame format. I try to rephrase it. > > 4.5.1: > 1) What is the EB source address size? Presumably the dst is short FFFF, > but it isn't stated. > XV: According to 15.4 -2015 page 65. "The Source Address field, if present, shall contain the address of the device sending the frame. When a device has associated and has been allocated a short address (i.e., macShortAddress is not equal to 0xfffe or 0xffff), it shall use that address in preference to its extended address (i.e., macExtendedAddress) wherever possible. When a device has not yet associated to a PAN, it shall use its extended address in all communications requiring the Source Address field. If the Source Address field is not present, the originator of the frame shall be assumed to be the PAN coordinator or RFD-TX device, and the Destination Address field shall contain the address of the recipient, optional for RFD-TX devices." The destination address should be 0xFFFF as you indicate. (short address). The source should be the node's extended address as per table 7-6 of 15.4-2015 (page 117) (12th row of the table). > 2) "While listening for EBs, a joining node set its own PAN ID to > 0xffff..." Why is the PAN ID set to FFFF? This implies that the EB either > doesn't have a dst PAN ID (contrary to the previous paragraph) or that > nodes accept EB's from any advertising PAN, which makes PANID not useful in > partitioning networks. > XV: This comes from some discussions we had some time back. I will try to find the threads. As far as I remember, the concern was that the PAN ID is not known by the node performing the scan. Then in order to be able to accept the EB following the filtering rules (level 3) defined in the 15.4-2011. section 5.1.6.2 or later in section 6.7.2 of 15.4-2015 the PAN ID has to be set to FFFF. I agree with you that we need to check this again. > 4.5.2: "EBs SHOULD NOT be used for time synchronization." The JN must > initially set it's clock from the EB, otherwise it will have no idea when > to send in its join request - see 6.2. I think you mean that EB's should > not be used for time synchronization after a node has K2? > XV: I agree. We need first to join the network. I will correct that. > > 4.6: How do you send in a join request using K2 (since it is a data frame > and not an EB) when you don't have K2 yet? > > XV: Good point. we do not say how K2 is provisioned. This is something that other documents in the WG should specify. In case K2 is pre-provisioned this is solved, however, the zero or one touch approaches should clarify this I guess. Do you have any suggestion for that? I understand that considering only minimal, if K2 is not pre-provisioned, we cannot join the network unless we use another mechanism. > Jonathan > > [email protected] > > -- Dr. Xavier Vilajosana Guillén Research Professor Wireless Networks Research Group Internet Interdisciplinary Institute (IN3) Universitat Oberta de Catalunya +34 646 633 681| [email protected] | Skype: xvilajosana http://xvilajosana.org http://wine.rdi.uoc.edu/ Parc Mediterrani de la Tecnologia Av. Carl Friedrich Gauss, 5. Edifici B3 08860 Castelldefels (Barcelona)
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