would create a header with the current packet information.
This allows sicslowpan to calculate the max payload size without
consuming a sequence number or clearing/restoring the packet buffer.
According to IEEE 802.15.4e (§6.4.3.9), in order to detect duplicate received
MAC-layer frames, only the most recently received frame's sequence number needs
to be stored for each unique device address. Doing so limits the possible false
duplicate packet detections to a single sequence number. This also allows to
keep the last sequence number of more device addresses for the same value of
MAX_SEQNOS.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
The code detecting duplicate packets in the RDC layer had been copied into most
RDC implementations. Factor it out into a new mac-sequence module in order to
have a single instance of this code.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
According to IEEE 802.15.4 (§5.1.6.1, §6.4.2), the MAC sequence numbers should
be initialized to random values. This was already the case in
framer-802154.c:create(), but not in csma.c:send_packet(), sometimes causing
false detections of duplicate MAC-layer packets in other devices when a device
was restarted too quickly. This patch decreases the probability of such an
event.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
interaction with the behavior of the rdc layer. If the first packet of a
fragment transmission was lost, the remaining packets would get dropped
on reception. Moreover, the reception code contained a bug that
sometimes would cause fragments to be misidentified as fragments. Taken
together, these problems would result in a pathelogical network
breakdown if too many fragmented packets would occur simultaneously.
* add a few rimestats to keep track of sent and received acks
* made a number of configuration options possible to override (ack timing)
* added the logic for sending 802.15.4 link layer ack packets, despite not being able to guarentee the 802.15.4 MAC timing
* increased the number of sequence numbers to keep track of for duplicate filtering
"Bridge mode" allows devices to more easily send 802.15.4 packets as if
they were a different device. It also turns off any packet filtering
that may be implemented at layer 2. It works by allowing
`PACKETBUF_ADDR_SENDER` to be set earlier in the stack.
This is useful for implementing 6LoWPAN-ethernet bridges.
Enabled via setting `NETSTACK_CONF_BRIDGE_MODE` to 1. Disabled by
default.
NETSTACK_ENCRYPT and NETSTACK_DECRYPT are defined. Those are intended
to be called as functions NETSTACK_ENCRYPT() and NETSTACK_DECRYPT() to
encrypt and decrypt the packetbuf, respectively. If needed, an
initialization function by the name NETSTACK_ENCRYPTION_INIT() can
also be defined.
