You can find an extensive evaluation of this implementation in our paper [*Orchestra: Robust Mesh Networks Through Autonomously Scheduled TSCH*](http://www.simonduquennoy.net/papers/duquennoy15orchestra.pdf), ACM SenSys'15.
## Features
This implementation includes:
* Standard IEEE 802.15.4e-2012 frame version 2
* Standard TSCH joining procedure with Enhanced Beacons with the following Information Elements:
On CC2420-based platforms, enable SFD timestamps with:
```
/* Disable DCO calibration (uses timerB) */
#undef DCOSYNCH_CONF_ENABLED
#define DCOSYNCH_CONF_ENABLED 0
/* Enable SFD timestamps (uses timerB) */
#undef CC2420_CONF_SFD_TIMESTAMPS
#define CC2420_CONF_SFD_TIMESTAMPS 1
```
To configure TSCH, see the macros in `.h` files under `core/net/mac/tsch/` and redefine your own in your `project-conf.h`.
## Using TSCH with Security
To include TSCH standard-compliant security, set the following:
```
/* Enable security */
#undef LLSEC802154_CONF_SECURITY_LEVEL
#define LLSEC802154_CONF_SECURITY_LEVEL 1
/* TSCH uses explicit keys to identify k1 and k2 */
#undef LLSEC802154_CONF_USES_EXPLICIT_KEYS
#define LLSEC802154_CONF_USES_EXPLICIT_KEYS 1
/* TSCH uses the ASN rather than frame counter to construct the Nonce */
#undef LLSEC802154_CONF_USES_FRAME_COUNTER
#define LLSEC802154_CONF_USES_FRAME_COUNTER 0
```
The keys can be configured in `net/mac/tsch/tsch-security.h`.
Nodes handle security level and keys dynamically, i.e. as specified by the incoming frame header rather that compile-time defined.
By default, when including security, the PAN coordinator will transmit secured EBs.
Use `tsch_set_pan_secured` to explicitly ask the coordinator to secure EBs or not.
When associating, nodes with security included can join both secured or non-secured networks.
Set `TSCH_CONF_JOIN_SECURED_ONLY` to force joining secured networks only.
Likewise, set `TSCH_JOIN_MY_PANID_ONLY` to force joining networks with a specific PANID only.
## TSCH Scheduling
By default (see `TSCH_SCHEDULE_WITH_6TISCH_MINIMAL`), our implementation runs a 6TiSCH minimal schedule, which emulates an always-on link on top of TSCH.
The schedule consists in a single shared slot for all transmissions and receptions, in a slotframe of length `TSCH_SCHEDULE_DEFAULT_LENGTH`.
As an alternative, we provide Orchestra (under `apps/orchestra`), an autonomous scheduling solution for TSCH where nodes maintain their own schedule locally, solely based on their local RPL state.
Orchestra can be simply enabled and should work out-of-the-box with its default settings as long as RPL is also enabled.
See `apps/orchestra/README.md` for more information.
Finally, one can also implement his own scheduler, centralized or distributed, based on the scheduling API provides in `core/net/mac/tsch/tsch-schedule.h`.
## Porting TSCH to a new platform
Porting TSCH to a new platform requires a few new features in the radio driver, a number of timing-related configuration paramters.
