6TiSCH X. Vilajosana, Ed.
Internet-Draft Universitat Oberta de Catalunya
Intended status: Informational K. Pister
Expires: May 23, 2014 University of California Berkeley
November 19, 2013
Minimal 6TiSCH Configuration
draft-ietf-6tisch-minimal-00
Abstract
This document describes the minimal set of rules to operate a
[IEEE802154e] Timeslotted Channel Hopping (TSCH) network. This
minimal mode of operation can be used during network bootstrap, as a
fallback mode of operation when no dynamic scheduling solution is
available or functioning, or during early interoperability testing
and development.
Status of This Memo
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This Internet-Draft will expire on May 23, 2014.
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Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Minimal Schedule Configuration . . . . . . . . . . . . . . . 3
2.1. Slotframe . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Cell Options . . . . . . . . . . . . . . . . . . . . . . 5
2.3. Retransmissions . . . . . . . . . . . . . . . . . . . . . 6
2.4. Time Slot timing . . . . . . . . . . . . . . . . . . . . 6
3. Enhanced Beacons Configuration and Content . . . . . . . . . 7
3.1. Sync IE . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.1.1. IE Header . . . . . . . . . . . . . . . . . . . . . . 8
3.1.2. IE Content . . . . . . . . . . . . . . . . . . . . . 8
3.2. Frame and Cell IE . . . . . . . . . . . . . . . . . . . . 8
3.2.1. IE Header . . . . . . . . . . . . . . . . . . . . . . 8
3.2.2. IE Content . . . . . . . . . . . . . . . . . . . . . 9
4. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 9
4.1. ACK/NACK Time Correction IE . . . . . . . . . . . . . . . 9
4.1.1. IE Header . . . . . . . . . . . . . . . . . . . . . . 9
4.1.2. IE Content . . . . . . . . . . . . . . . . . . . . . 9
5. Neighbour information . . . . . . . . . . . . . . . . . . . . 10
5.1. Neighbour Table . . . . . . . . . . . . . . . . . . . . . 10
5.2. Time Source Neighbour Selection . . . . . . . . . . . . . 11
6. Queues and Priorities . . . . . . . . . . . . . . . . . . . . 11
7. RPL on TSCH . . . . . . . . . . . . . . . . . . . . . . . . . 12
7.1. RPL Objective Function Zero . . . . . . . . . . . . . . . 12
7.1.1. Rank computation . . . . . . . . . . . . . . . . . . 12
7.1.2. Rank computation Example . . . . . . . . . . . . . . 13
7.2. RPL Configuration . . . . . . . . . . . . . . . . . . . . 14
7.2.1. Mode of Operation . . . . . . . . . . . . . . . . . . 15
7.2.2. Trickle Timer . . . . . . . . . . . . . . . . . . . . 15
7.2.3. Hysteresis . . . . . . . . . . . . . . . . . . . . . 15
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
9.1. Normative References . . . . . . . . . . . . . . . . . . 15
9.2. Informative References . . . . . . . . . . . . . . . . . 16
9.3. External Informative References . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
The nodes in a [IEEE802154e] TSCH network follow a communication
schedule. The entity (centralized or decentralized) responsible for
building and maintaining that schedule has very precise control over
the trade-off between the network's latency, bandwidth, reliability
and power consumption. During early interoperability testing and
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development, however, simplicity is often more important than
efficiency. One goal of this document is to define the simplest set
of rules for building a [IEEE802154e] TSCH-compliant network, at the
necessary price of lesser efficiency. Yet, this minimal mode of
operation can also be used during network bootstrap before any
schedule is installed into the network so nodes can self organize and
the management and configuration information be distributed. In
addition, as outlined in
[I-D.phinney-roll-rpl-industrial-applicability] the minimal
configuration can be used as a fallback mode of operation, ensuring
connectivity of nodes in case that dynamic scheduling mechanisms fail
or are not available. [IEEE802154e] provides a mechanism whereby the
details of slotframe length, timeslot timing, and channel hopping
pattern are communicated at synchronization to a node, also Enhanced
Beacons can be used to periodically update nodes information. This
document describes specific settings for these parameters. Nodes
SHOULD broadcast properly formed Enhanced Beacons to announce these
values, but during initial implementation and debugging it may be
convenient to hard-code these values.
2. Minimal Schedule Configuration
In order to form a network, a minimum schedule configuration is
required so nodes can advertise the presence of the network, and
allow other nodes to join.
2.1. Slotframe
The slotframe, as defined in [I-D.ietf-6tisch-terminology], is an
abstraction of the MAC layer that defines a collection of time slots
of equal length and priority, and which repeats over time. In order
to set up a minimal TSCH network, nodes need to be synchronized with
the same slotframe configuration so they can exchange Enhanced
Beacons (EBs) and data packets. This document recommends the
following slotframe configuration.
Minimal configuration
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+------------------------------------+----------------------+
| Property | Value |
+------------------------------------+----------------------+
| Number of time slots per Slotframe | 101 |
+------------------------------------+----------------------+
| Number of available channels | 16 |
+------------------------------------+----------------------+
| Number of EBs cells | 1 (slotOffset 0) |
+------------------------------------+----------------------+
| Number of scheduled cells | 5 (slotOffsets |
| | 1,2,3,4,5) |
+------------------------------------+----------------------+
| Number of unscheduled cells | 95 (from slotOffset |
| | 6 to 100) |
+------------------------------------+----------------------+
| Number of MAC retransmissions (max)| 3 |
+------------------------------------+----------------------+
| Time Slot duration | 15ms |
+------------------------------------+----------------------+
The suggested minimal schedule may be hard-coded in each node. The
slotframe is composed of 101 time slots. The first slot in the
slotframe is used to send Enhanced Beacons announcing the presence of
the network. These EBs are not acknowledged. Five cells are
scheduled for exchanging data packets, as described in Section 2.2.
These cells are scheduled at slotOffset 1 to 5, and channeOffset 0.
Per the IEEE802.15.4e TSCH, data packets sent on these cells to a
unicast MAC address are acknowledged by the receiver. The 95
remaining cells are unscheduled, but are available to be allocated by
dynamic scheduling solutions.
Minimal schedule overview
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+-----+-----+-----+-----+-----+-----+-----+ +-----+
chan.Off. 0 | EB |TxRxS|TxRxS|TxRxS|TxRxS|TxRxS| OFF | ... | OFF |
+-----+-----+-----+-----+-----+-----+-----+ +-----+
chan.Off. 1 | | | | | | | | ... | |
+-----+-----+-----+-----+-----+-----+-----+ +-----+
...
+-----+-----+-----+-----+-----+-----+-----+ +-----+
chan.Off. 15 | | | | | | | | ... | |
+-----+-----+-----+-----+-----+-----+-----+ +-----+
0 1 2 3 4 5 6 100
EB: Enhanced Beacon
Tx: Transmit
Rx: Receive
S: Shared
OFF: Unscheduled (can be used by a dynamic scheduling mechanism)
2.2. Cell Options
Per the [IEEE802154e] TSCH, each scheduled cell has a bitmap of cell
options assigned, named LinkOption. All scheduled cells in the
minimal schedule are configured as Hard cells
[I-D.watteyne-6tisch-tsch][I-D.wang-6tisch-6top]. Additional
available cells can be scheduled by a dynamic scheduling solution and
can either be configured as hard cells or soft cells without any
restriction.
The EB cell is assigned the following bitmap of cell options:
b0 = Transmit = 1 (set)
b1 = Receive = 0 (clear)
b2 = Shared = 0 (clear)
b3 = Timekeeping = 0 (clear)
b4 = Hard = 1 (set)
b5-b7 = Reserved (clear)
The data cells are assigned the bitmap of cell options below that
results in "Slotted Aloha" behaviour. Because both the "Transmit"
and "Receive" bits are set, a node either transmits, if there is a
packet in its queue, or listens if it has nothing to transmit.
Because the "shared" bit is set, the back-off mechanism defined in
[IEEE802154e] is used to resolve contention.
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b0 = Transmit = 1 (set)
b1 = Receive = 1 (set)
b2 = Shared = 1 (set)
b3 = Timekeeping = 0 (clear)
b4 = Hard = 1 (set)
b5-b7 = Reserved (clear)
All remaining cells are unscheduled. Thus the nodes can keep their
radio off. In a memory efficient implementation, scheduled cells
could be represented by a circular linked list. Unscheduled cells
SHOULD NOT occupy any memory.
2.3. Retransmissions
The maximum number of MAC-layer retransmissions is set to 3. For
packets which require an acknowledgement, if none is received after a
total of 4 attempts, the transmissions is considered failed and the
MAC layer MUST notify the upper layer. Packets sent to the broadcast
MAC address (including EBs) are not acknowledged and therefore not
retransmitted.
2.4. Time Slot timing
The figure below shows an active timeslot in which a packet is sent
from the transmitter node (TX) to the receiver node (RX). A MAC
acknowledgement is sent back from the RX to the TX node, indicating
successful reception. The TsTxOffset duration defines the instant in
the timeslot when the first byte of the transmitted packet leaves the
radio of the TX node. The radio of the RX node is turned on TsLongGT
/2 before that instant, and listen for at least TsLongGT. This
allows for a de-synchronization between the two node of at most
TsLongGT. The RX node needs to send the first byte of the MAC
acknowledgement exactly TsTxAckDelay after the end of the last byte
of the received packet. TX's radio has to be turned on TsShortGT/2
before that time, and keep listening for at least TsShortGT.
Time slot internal timing diagram
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/------------------- Time Slot duration --------------------/
| /tsShortGT/ |
| | | | | |
|------------+-----------------+--------------+------+------|
TX | | TX-Packet | |RX Ack| |
|------------+-----------------+--------------+------+------|
|/tsTxOffset/| | | | |
| | | | | |
|------------+-----------------+--------------+------+------|
RX | | | | RX-Packet | |TX Ack| |
|---------+--+--+--------------+--------------+------+------|
| | | | | | | |
| /tsLongGT/ |/TsTxAckDelay/| | |
Start End
of of
Slot Slot
[IEEE802154e] does not define the different durations of a time slot.
It does allow those durations to be sent in the EBs (through a
TimeSlot IE). This document recommends to pre-configure the
different durations to the values listed below or use EBs to learn
those values included in the TimeSlot IE.
Timeslot durations
+---------------------------------+------------------+
| IEEE802.15.4e TSCH parameter | Value |
+---------------------------------+------------------+
| TsTxOffset | 4000us |
+---------------------------------+------------------+
| TsLongGT | 2600us |
+---------------------------------+------------------+
| TsTxAckDelay | 4606us |
+---------------------------------+------------------+
| TsShortGT | 1000us |
+---------------------------------+------------------+
| Time Slot duration | 15000us |
+---------------------------------+------------------+
3. Enhanced Beacons Configuration and Content
[IEEE802154e] does not define how often or which EBs are sent. The
choice of the duration between two EBs needs to take into account
whether EBs are used as the only mechanism to synchronize devices, or
whether a Keep-Alive (KA) mechanism is used in parallel. For a
simplest TSCH configuration, a mote SHOULD send an EB every 10s. For
additional reference see [I-D.watteyne-6tisch-tsch] where different
synchronization approaches are summarized.
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EBs MUST be sent with the Beacon IEEE802.15.4 frame type and this EBs
MUST carry the following Information Elements (IEs): (The content of
the IEs is presented here for clarity, however this information is
redundant with [I-D.watteyne-6tisch-tsch] and [IEEE802154e].)
3.1. Sync IE
Contains synchronization information such as ASN and Join Priority.
The value of Join Priority is discussed in Section 5.2.
3.1.1. IE Header
Length (b0-b7) = 0x06
Sub-ID (b8-b14) = 0x1a
Type (b15) = 0x00 (short)
3.1.2. IE Content
ASN Byte 1 (b16-b23)
ASN Byte 2 (b24-b31)
ASN Byte 3 (b32-b39)
ASN Byte 4 (b40-b47)
ASN Byte 5 (b48-b55)
Join Priority (b56-b63)
3.2. Frame and Cell IE
Although the schedule may be hard-coded during development, each node
MUST indicate the schedule in each EB through a Frame and Cell IE.
This enables nodes which implement [IEEE802154e] fully to configure
their schedule as they join the network, and interact with nodes
using a hard-coded schedule.
3.2.1. IE Header
Length (b0-b7) = variable
Sub-ID (b8-b14) = 0x1b
Type (b15) = 0x00 (short)
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3.2.2. IE Content
# Slotframes (b16-b23) = 0x01
Slotframe ID (b24-b31) = 0x01
Size Slotframe (b32-b47) = 0x65 (101)
# Links (b48-b55) = 0x06
For each link in the minimal schedule:
Channel Offset (2B) = 0x00
Slot Number (2B) = from 0x00 to 0x05
LinkOption (1B) = as described in Section 2.2
4. Acknowledgement
MAC-layer acknowledgement frames are built according to
[IEEE802154e]. Data frames and command frames sent to a unicast MAC
destination address request an acknowledgement. The acknowledgement
frame is of type ACK (0x10). Each acknowledgement contains the
following IE:
4.1. ACK/NACK Time Correction IE
The ACK/NACK time correction IE is used to carry the measured de-
synchronization between the sender and the receiver.
4.1.1. IE Header
Length (b0-b7) = 0x02
Sub-ID (b8-b14) = 0x1e
Type (b15) = 0x00 (short)
4.1.2. IE Content
Time Synch Info and ACK status (b16-b31)
The possible values for the Time Synch Info and ACK status are
described in [IEEE802154e] and reproduced in the following table:
ACK status and Time Synchronization information.
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+-----------------------------------+------------------+
| ACK Status | Value |
+-----------------------------------+------------------+
| ACK with positive time correction | 0x0000 - 0x07ff |
+-----------------------------------+------------------+
| ACK with negative time correction | 0x0800 - 0x0fff |
+-----------------------------------+------------------+
| NACK with positive time correction| 0x8000 - 0x87ff |
+-----------------------------------+------------------+
| NACK with negative time correction| 0x8800 - 0x8fff |
+-----------------------------------+------------------+
5. Neighbour information
[IEEE802154e] does not define how and when each node in the network
keeps information about its neighbours. This document recommends to
keep the following information in the Neighbour table:
5.1. Neighbour Table
The exact format of the neighbour table is implementation-specific,
but it SHOULD contain the following information for each neighbour:
Neighbour statistics:
numTx: number of transmitted packets to that neighbour
numTxAck: number of transmitted packets that have been
acknowledged by that neighbour
numRx: number of received packets from that neighbour
The EUI64 of the neighbour address.
Timestamp when that neighbour was heard for the last time. This
can be based on the ASN counter or any other time base. Can be
used to trigger a keep-alive message.
RPL rank of that neighbour.
A flag which indicates whether this neighbour is a time source
neighbour.
Connectivity statistics (e.g., RSSI), which can be used to
determine the quality of the link.
In addition of that information, each node has to be able to compute
some RPL Objective Function (OF) taking into account the neighbour
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and connectivity statistics. An example RPL objective function is
the OF Zero as described in [RFC6552] and Section 7.1.1.
5.2. Time Source Neighbour Selection
Each node MUST select at least one time source neighbour amongst its
known neighbours in its RPL routing parent set. When a node joins a
network, it has no routing information yet. To select its time
source neighbour, uses the Join Priority information advertised in
the EB as described in Section 5.2.4.13 and Table 52b of
[IEEE802154e]. The Sync IE contains the ASN and 1 Byte field named
Join Priority. The Join Priority of any node is equivalent to the
result of the function DAGRank(rank) as defined by [RFC6550] and
Section 7.1.1. The Join Priority of the DAG root is zero, i.e., EBs
sent from the DAG root are sent with Join Priority equal to 0. A
lower value of the Join Priority indicates that the device is the
preferred one to connect to. When a node Joins the network MUST NOT
be allowed to send EBs until it has acquired a RPL rank. The latter
avoids topology loops and matches RPL topology with underlying mesh
topology. As soon as a node acquires a RPL rank (see [RFC6550] and
Section 7.1.1), it SHOULD send Enhanced Beacons including a Sync IE
with Join Priority field set as DAGRank(rank) where rank is the rank
of the actual node. In case of a node receives EBs from different
nodes with equal Join Priority, the time source neighbour selection
should be assessed by other metrics that can help to determine the
better connectivity link. Time source neighbor hysteresis SHOULD be
addressed according to the rules defined in Section 7.2.3. If
connectivity to the time source neighbor is lost, a new time source
neighbor MUST be chosen among the neighbor in the RPL routing parent
set.
Optionally, some form of hysteresis SHOULD be implemented to avoid
frequent changes in time source neighbors.
6. Queues and Priorities
[IEEE802154e] does not define the use of queues to handle upper layer
data (either application or control data from upper layers). This
document recommends the use of a single queue with the following
rules:
When the node is not synchronized to the network, higher layers
are not able to insert packets into the queue.
Frames generated by the MAC layer (e.g., EBs and ACK) have a
higher priority than packets received from a higher layer.
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IEEE802.15.4 frames of types Beacon and Command have a higher
priority than IEEE802.15.4 frames of types Data and ACK.
One entry in the queue is reserved at all times for an
IEEE802.15.4 frames of types Beacon or Command frames.
7. RPL on TSCH
Nodes in the network MUST use the RPL routing protocol
7.1. RPL Objective Function Zero
Nodes in the network MUST use the RPL routing protocol [RFC6550].
7.1.1. Rank computation
The rank computation is described at [RFC6552] Section 4.1. Briefly,
a node rank is computed by the following equation:
R(N) = R(P) + rank_increase
rank_increase = (Rf*Sp + Sr) * MinHopRankIncrease
Where:
R(N): Rank of the node.
R(P): Rank of the parent obtained as part of the DIO information.
rank_increase: The result of a function that determines the rank
increment.
Rf (rank_factor): A configurable factor that is used to multiply
the effect of the link properties in the rank_increase
computation. If none is configured, then a rank_factor of 1 is
used. For the purpose of this document rank_factor MUST be set to
1.
Sp (step_of_rank): (strictly positive integer) - an intermediate
computation based on the link properties with a certain neighbour.
For the purpose of this document 2*ETX (Expected Transmissions) as
defined by [DeCouto03] and [RFC6551] MUST be used. The ETX will
be computed as the inverse of the Packet Delivery Ratio (PDR)
computed as the number of acknowledged packets divided by the
number of transmitted packets to a certain node. E.g: Sp=2*numTX/
numTXAck
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Sr (stretch_of_rank): (unsigned integer) - the maximum
augmentation to the step_of_rank of a preferred parent to allow
the selection of an additional feasible successor. If none is
configured to the device, then the step_of_rank is not stretched.
For the present document stretch_of_rank MUST be set to 0.
MinHopRankIncrease: the MinHopRankIncrease is set to the fixed
constant DEFAULT_MIN_HOP_RANK_INCREASE [RFC6550].
DEFAULT_MIN_HOP_RANK_INCREASE has a value of 256.
DAGRank(rank): Equivalent to the floor of (Rf*Sp + Sr) as defined
by [RFC6550]. Specifically, when an Objective Function computes
Rank this is defined as an unsigned integer (i.e., 16-bit) Rank
quantity. When the Rank is compared, e.g., for determination of
parent relationships or loop detection, the integer portion of the
Rank is used. The integer portion of the Rank is computed by the
DAGRank() macro as floor(x) where floor(x) is the function that
evaluates to the greatest integer less than or equal to x.
DAGRank(rank) = floor(rank/MinHopRankIncrease)
Rank computation scenario
+-------+
| P | R(P)
| |
+-------+
|
|
|
+-------+
| N | R(N)=R(P) + rank_increase
| | rank_increase = (Rf*Sp + Sr) * MinHopRankIncrease
+-------+ Sp=2*ETX
7.1.2. Rank computation Example
This sections illustrates with an example the use of the Objective
Function Zero. Assume the following parameters:
Rf = 1
Sp = 2* ETX
Sr = 0
minHopRankIncrease = 256 (default in RPL)
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ETX=(numTX/numTXAck)
r(n) = r(p) + rank_increase
rank_increase = (Rf*Sp + Sr) * minHopRankIncrease
rank_increase = 512*numTx/numTxACK
Rank computation example for 5 hop network where numTx=100 and
numTxAck=75 for all nodes
+-------+
| 0 | R(0)=0
| | DAGRank(R(0)) = 0
+-------+
|
|
+-------+
| 1 | R(1)=R(0)+683=683
| | DAGRank(R(1)) = 2
+-------+
|
|
+-------+
| 2 | R(2)=R(1)+683=1366
| | DAGRank(R(2)) = 5
+-------+
|
|
+-------+
| 3 | R(3)=R(2)+683=2049
| | DAGRank(R(3)) = 8
+-------+
|
|
+-------+
| 4 | R(4)=R(3)+683=2732
| | DAGRank(R(4)) = 10
+-------+
|
|
+-------+
| 5 | R(5)=R(4)+683=3415
| | DAGRank(R(5)) = 13
+-------+
7.2. RPL Configuration
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In addition to the Objective Function (OF), a minimal configuration
for RPL should indicate the preferred mode of operation and trickle
timer operation so different RPL implementations can interoperate.
7.2.1. Mode of Operation
For downstream route maintenance, in a minimal configuration, RPL
MUST be set to operate in the Non-Storing mode as described by
[RFC6550] Section 9.7. Storing mode ([RFC6550] Section 9.8) MAY be
supported in less constrained devices.
7.2.2. Trickle Timer
RPL signalling messages such as DIOs are sent using the Trickle
Algorithm [RFC6550] (Section 8.3.1) and [RFC6206]. For the purpose
of this document, the Trickle Timer MUST be used with the RPL defined
default values [RFC6550] (Section 8.3.1). For a description of the
Trickle timer operation see Section 4.2 on [RFC6206].
7.2.3. Hysteresis
According to [RFC6552] the [RFC6719] recommends the use of a boundary
value (PARENT_SWITCH_THRESHOLD) to avoid constant changes of parent
when ranks are compared. When evaluating a parent that belongs to a
smaller path cost than current minimum path, the candidate node is
selected as new parent only if the difference between the new path
and the current path is greater than the defined
PARENT_SWITCH_THRESHOLD. Otherwise the node MAY continue to use the
current preferred parent. As for [RFC6719] the recommended value for
PARENT_SWITCH_THRESHOLD is 192 when ETX metric is used, the
recommendation for this document is to use PARENT_SWITCH_THRESHOLD
equal to 394 as the metric being used is 2*ETX. This is mechanism is
suited to deal with parent hysteresis in both cases routing parent
and time source neighbor selection.
8. Acknowledgements
The authors would like to acknowledge the guidance and input provided
by the 6TiSCH Chairs Pascal Thubert and Thomas Watteyne.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
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[RFC6206] Levis, P., Clausen, T., Hui, J., Gnawali, O., and J. Ko,
"The Trickle Algorithm", RFC 6206, March 2011.
[RFC6550] Winter, T., Thubert, P., Brandt, A., Hui, J., Kelsey, R.,
Levis, P., Pister, K., Struik, R., Vasseur, JP., and R.
Alexander, "RPL: IPv6 Routing Protocol for Low-Power and
Lossy Networks", RFC 6550, March 2012.
[RFC6551] Vasseur, JP., Kim, M., Pister, K., Dejean, N., and D.
Barthel, "Routing Metrics Used for Path Calculation in
Low-Power and Lossy Networks", RFC 6551, March 2012.
[RFC6552] Thubert, P., "Objective Function Zero for the Routing
Protocol for Low-Power and Lossy Networks (RPL)", RFC
6552, March 2012.
[RFC6719] Gnawali, O. and P. Levis, "The Minimum Rank with
Hysteresis Objective Function", RFC 6719, September 2012.
9.2. Informative References
[I-D.watteyne-6tisch-tsch]
Watteyne, T., Palattella, M., and L. Grieco, "Using
IEEE802.15.4e TSCH in an LLN context: Overview, Problem
Statement and Goals", draft-watteyne-6tisch-tsch-00 (work
in progress), October 2013.
[I-D.ietf-6tisch-architecture]
Thubert, P., Watteyne, T., and R. Assimiti, "An
Architecture for IPv6 over the TSCH mode of IEEE
802.15.4e", draft-ietf-6tisch-architecture-00 (work in
progress), November 2013.
[I-D.ietf-6tisch-terminology]
Palattella, M., Thubert, P., Watteyne, T., and Q. Wang,
"Terminology in IPv6 over the TSCH mode of IEEE
802.15.4e", draft-ietf-6tisch-terminology-00 (work in
progress), November 2013.
[I-D.wang-6tisch-6top]
Wang, Q., Vilajosana, X., and T. Watteyne, "6TiSCH
Operation Sublayer (6top)", draft-wang-6tisch-6top-00
(work in progress), October 2013.
[I-D.ohba-6tisch-security]
Vilajosana & Pister Expires May 23, 2014 [Page 16]
Internet-Draft 6tisch-minimal November 2013
Chasko, S., Das, S., Lopez, R., Ohba, Y., Thubert, P., and
A. Yegin, "Security Framework and Key Management Protocol
Requirements for 6TiSCH", draft-ohba-6tisch-security-00
(work in progress), October 2013.
[I-D.ietf-roll-terminology]
Vasseur, J., "Terms used in Routing for Low power And
Lossy Networks", draft-ietf-roll-terminology-13 (work in
progress), October 2013.
[I-D.phinney-roll-rpl-industrial-applicability]
Phinney, T., Thubert, P., and R. Assimiti, "RPL
applicability in industrial networks", draft-phinney-roll-
rpl-industrial-applicability-02 (work in progress),
February 2013.
9.3. External Informative References
[IEEE802154e]
IEEE standard for Information Technology, "IEEE std.
802.15.4e, Part. 15.4: Low-Rate Wireless Personal Area
Networks (LR-WPANs) Amendment 1: MAC sublayer", April
2012.
[IEEE802154]
IEEE standard for Information Technology, "IEEE std.
802.15.4, Part. 15.4: Wireless Medium Access Control (MAC)
and Physical Layer (PHY) Specifications for Low-Rate
Wireless Personal Area Networks", June 2011.
[DeCouto03]
De Couto, D., Aguayo, D., Bicket, J., and R. Morris, "A
High-Throughput Path Metric for Multi-Hop Wireless
Routing", MobiCom '03, The 9th ACM International
Conference on Mobile Computing and Networking, San Diego,
California", June 2003.
[OpenWSN] , "Berkeley's OpenWSN Project Homepage",
<http://www.openwsn.org/>.
Authors' Addresses
Vilajosana & Pister Expires May 23, 2014 [Page 17]
Internet-Draft 6tisch-minimal November 2013
Xavier Vilajosana (editor)
Universitat Oberta de Catalunya
156 Rambla Poblenou
Barcelona, Catalonia 08018
Spain
Phone: +34 (646) 633 681
Email: xvilajosana@uoc.edu
Kris Pister
University of California Berkeley
490 Cory Hall
Berkeley, California 94720
USA
Email: pister@eecs.berkeley.edu
Vilajosana & Pister Expires May 23, 2014 [Page 18]
