diff --git a/apps/federatedfilesharing/lib/AppInfo/Application.php b/apps/federatedfilesharing/lib/AppInfo/Application.php
index 23f521a51c..655c01cf85 100644
--- a/apps/federatedfilesharing/lib/AppInfo/Application.php
+++ b/apps/federatedfilesharing/lib/AppInfo/Application.php
@@ -33,6 +33,7 @@ use OCA\FederatedFileSharing\Controller\RequestHandlerController;
 use OCA\FederatedFileSharing\FederatedShareProvider;
 use OCA\FederatedFileSharing\Notifications;
 use OCA\FederatedFileSharing\OCM\CloudFederationProvider;
+use OCA\FederatedFileSharing\OCM\CloudFederationProviderFiles;
 use OCP\AppFramework\App;
 use OCP\GlobalScale\IConfig;
 
@@ -51,7 +52,18 @@ class Application extends App {
 		$cloudFederationManager->addCloudFederationProvider('file',
 			'Federated Files Sharing',
 			function() use ($container) {
-				return new CloudFederationProvider('file');
+				$server = $container->getServer();
+				return new CloudFederationProviderFiles(
+					$server->getAppManager(),
+					$server->query(FederatedShareProvider::class),
+					$server->query(AddressHandler::class),
+					$server->getLogger(),
+					$server->getUserManager(),
+					$server->getCloudIdManager(),
+					$server->getActivityManager(),
+					$server->getNotificationManager(),
+					$server->getURLGenerator()
+				);
 			});
 
 		$container->registerService('RequestHandlerController', function(SimpleContainer $c) use ($server) {
@@ -76,7 +88,9 @@ class Application extends App {
 				$addressHandler,
 				$server->getUserManager(),
 				$server->getCloudIdManager(),
-				$server->getLogger()
+				$server->getLogger(),
+				$server->getCloudFederationFactory(),
+				$server->getCloudFederationProviderManager()
 			);
 		});
 	}
diff --git a/apps/federatedfilesharing/lib/Controller/RequestHandlerController.php b/apps/federatedfilesharing/lib/Controller/RequestHandlerController.php
index 422f12dda2..2d0a3c528f 100644
--- a/apps/federatedfilesharing/lib/Controller/RequestHandlerController.php
+++ b/apps/federatedfilesharing/lib/Controller/RequestHandlerController.php
@@ -40,6 +40,10 @@ use OCP\AppFramework\OCS\OCSForbiddenException;
 use OCP\AppFramework\OCS\OCSNotFoundException;
 use OCP\AppFramework\OCSController;
 use OCP\Constants;
+use OCP\Federation\Exceptions\ProviderCouldNotAddShareException;
+use OCP\Federation\Exceptions\ProviderDoesNotExistsException;
+use OCP\Federation\ICloudFederationFactory;
+use OCP\Federation\ICloudFederationProviderManager;
 use OCP\Federation\ICloudIdManager;
 use OCP\Files\NotFoundException;
 use OCP\IDBConnection;
@@ -78,6 +82,12 @@ class RequestHandlerController extends OCSController {
 	/** @var ILogger */
 	private $logger;
 
+	/** @var ICloudFederationFactory */
+	private $cloudFederationFactory;
+
+	/** @var ICloudFederationProviderManager */
+	private $cloudFederationProviderManager;
+
 	/**
 	 * Server2Server constructor.
 	 *
@@ -90,6 +100,9 @@ class RequestHandlerController extends OCSController {
 	 * @param AddressHandler $addressHandler
 	 * @param IUserManager $userManager
 	 * @param ICloudIdManager $cloudIdManager
+	 * @param ILogger $logger
+	 * @param ICloudFederationFactory $cloudFederationFactory
+	 * @param ICloudFederationProviderManager $cloudFederationProviderManager
 	 */
 	public function __construct($appName,
 								IRequest $request,
@@ -100,7 +113,9 @@ class RequestHandlerController extends OCSController {
 								AddressHandler $addressHandler,
 								IUserManager $userManager,
 								ICloudIdManager $cloudIdManager,
-								ILogger $logger
+								ILogger $logger,
+								ICloudFederationFactory $cloudFederationFactory,
+								ICloudFederationProviderManager $cloudFederationProviderManager
 	) {
 		parent::__construct($appName, $request);
 
@@ -112,6 +127,8 @@ class RequestHandlerController extends OCSController {
 		$this->userManager = $userManager;
 		$this->cloudIdManager = $cloudIdManager;
 		$this->logger = $logger;
+		$this->cloudFederationFactory = $cloudFederationFactory;
+		$this->cloudFederationProviderManager = $cloudFederationProviderManager;
 	}
 
 	/**
@@ -125,10 +142,6 @@ class RequestHandlerController extends OCSController {
 	 */
 	public function createShare() {
 
-		if (!$this->isS2SEnabled(true)) {
-			throw new OCSException('Server does not support federated cloud sharing', 503);
-		}
-
 		$remote = isset($_POST['remote']) ? $_POST['remote'] : null;
 		$token = isset($_POST['token']) ? $_POST['token'] : null;
 		$name = isset($_POST['name']) ? $_POST['name'] : null;
@@ -139,92 +152,41 @@ class RequestHandlerController extends OCSController {
 		$sharedByFederatedId = isset($_POST['sharedByFederatedId']) ? $_POST['sharedByFederatedId'] : null;
 		$ownerFederatedId = isset($_POST['ownerFederatedId']) ? $_POST['ownerFederatedId'] : null;
 
-		if ($remote && $token && $name && $owner && $remoteId && $shareWith) {
-
-			if (!\OCP\Util::isValidFileName($name)) {
-				throw new OCSException('The mountpoint name contains invalid characters.', 400);
-			}
-
-			// FIXME this should be a method in the user management instead
-			$this->logger->debug('shareWith before, ' . $shareWith, ['app' => 'files_sharing']);
-			\OCP\Util::emitHook(
-				'\OCA\Files_Sharing\API\Server2Server',
-				'preLoginNameUsedAsUserName',
-				array('uid' => &$shareWith)
-			);
-			$this->logger->debug('shareWith after, ' . $shareWith, ['app' => 'files_sharing']);
-
-			if (!\OC::$server->getUserManager()->userExists($shareWith)) {
-				throw new OCSException('User does not exists', 400);
-			}
-
-			\OC_Util::setupFS($shareWith);
-
-			$externalManager = new \OCA\Files_Sharing\External\Manager(
-					\OC::$server->getDatabaseConnection(),
-					\OC\Files\Filesystem::getMountManager(),
-					\OC\Files\Filesystem::getLoader(),
-					\OC::$server->getHTTPClientService(),
-					\OC::$server->getNotificationManager(),
-					\OC::$server->query(\OCP\OCS\IDiscoveryService::class),
-					$shareWith
-				);
-
-			try {
-				$externalManager->addShare($remote, $token, '', $name, $owner, false, $shareWith, $remoteId);
-				$shareId = \OC::$server->getDatabaseConnection()->lastInsertId('*PREFIX*share_external');
-
-				if ($ownerFederatedId === null) {
-					$ownerFederatedId = $this->cloudIdManager->getCloudId($owner, $this->cleanupRemote($remote))->getId();
-				}
-				// if the owner of the share and the initiator are the same user
-				// we also complete the federated share ID for the initiator
-				if ($sharedByFederatedId === null && $owner === $sharedBy) {
-					$sharedByFederatedId = $ownerFederatedId;
-				}
-
-				$event = \OC::$server->getActivityManager()->generateEvent();
-				$event->setApp('files_sharing')
-					->setType('remote_share')
-					->setSubject(RemoteShares::SUBJECT_REMOTE_SHARE_RECEIVED, [$ownerFederatedId, trim($name, '/')])
-					->setAffectedUser($shareWith)
-					->setObject('remote_share', (int)$shareId, $name);
-				\OC::$server->getActivityManager()->publish($event);
-
-				$urlGenerator = \OC::$server->getURLGenerator();
-
-				$notificationManager = \OC::$server->getNotificationManager();
-				$notification = $notificationManager->createNotification();
-				$notification->setApp('files_sharing')
-					->setUser($shareWith)
-					->setDateTime(new \DateTime())
-					->setObject('remote_share', $shareId)
-					->setSubject('remote_share', [$ownerFederatedId, $sharedByFederatedId, trim($name, '/')]);
-
-				$declineAction = $notification->createAction();
-				$declineAction->setLabel('decline')
-					->setLink($urlGenerator->getAbsoluteURL($urlGenerator->linkTo('', 'ocs/v2.php/apps/files_sharing/api/v1/remote_shares/pending/' . $shareId)), 'DELETE');
-				$notification->addAction($declineAction);
-
-				$acceptAction = $notification->createAction();
-				$acceptAction->setLabel('accept')
-					->setLink($urlGenerator->getAbsoluteURL($urlGenerator->linkTo('', 'ocs/v2.php/apps/files_sharing/api/v1/remote_shares/pending/' . $shareId)), 'POST');
-				$notification->addAction($acceptAction);
-
-				$notificationManager->notify($notification);
-
-				return new Http\DataResponse();
-			} catch (\Exception $e) {
-				$this->logger->logException($e, [
-					'message' => 'Server can not add remote share.',
-					'level' => ILogger::ERROR,
-					'app' => 'files_sharing'
-				]);
-				throw new OCSException('internal server error, was not able to add share from ' . $remote, 500);
-			}
+		if ($ownerFederatedId === null) {
+			$ownerFederatedId = $this->cloudIdManager->getCloudId($owner, $this->cleanupRemote($remote))->getId();
+		}
+		// if the owner of the share and the initiator are the same user
+		// we also complete the federated share ID for the initiator
+		if ($sharedByFederatedId === null && $owner === $sharedBy) {
+			$sharedByFederatedId = $ownerFederatedId;
 		}
 
-		throw new OCSException('server can not add remote share, missing parameter', 400);
+		$share = $this->cloudFederationFactory->getCloudFederationShare(
+			$shareWith,
+			$name,
+			'',
+			$remoteId,
+			$ownerFederatedId,
+			$owner,
+			$sharedByFederatedId,
+			$sharedBy,
+			['name' => 'webdav', 'options' => ['access_token' => $token]],
+			'user',
+			'file'
+		);
+
+		try {
+			$provider = $this->cloudFederationProviderManager->getCloudFederationProvider('file');
+			$provider->shareReceived($share);
+		} catch (ProviderDoesNotExistsException $e) {
+			throw new OCSException('Server does not support federated cloud sharing', 503);
+		} catch (ProviderCouldNotAddShareException $e) {
+			throw new OCSException($e->getMessage(), $e->getCode());
+		} catch (\Exception $e) {
+			throw new OCSException('internal server error, was not able to add share from ' . $remote, 500);
+		}
+
+		return new Http\DataResponse();
 	}
 
 	/**
diff --git a/apps/federatedfilesharing/lib/FederatedShareProvider.php b/apps/federatedfilesharing/lib/FederatedShareProvider.php
index d2962d9c59..ecc1e1710b 100644
--- a/apps/federatedfilesharing/lib/FederatedShareProvider.php
+++ b/apps/federatedfilesharing/lib/FederatedShareProvider.php
@@ -30,7 +30,6 @@
 namespace OCA\FederatedFileSharing;
 
 use OC\Share20\Share;
-use OCA\FederatedFileSharing\OCM\CloudFederationProvider;
 use OCP\Federation\ICloudIdManager;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\Files\Folder;
@@ -92,9 +91,6 @@ class FederatedShareProvider implements IShareProvider {
 	/** @var \OCP\GlobalScale\IConfig */
 	private $gsConfig;
 
-	/** @var CloudFederationProvider */
-	private $cloudFederationProvider;
-
 	/**
 	 * DefaultShareProvider constructor.
 	 *
@@ -109,7 +105,6 @@ class FederatedShareProvider implements IShareProvider {
 	 * @param IUserManager $userManager
 	 * @param ICloudIdManager $cloudIdManager
 	 * @param \OCP\GlobalScale\IConfig $globalScaleConfig
-	 * @param CloudFederationProvider $cloudFederationProvider
 	 */
 	public function __construct(
 			IDBConnection $connection,
@@ -122,8 +117,7 @@ class FederatedShareProvider implements IShareProvider {
 			IConfig $config,
 			IUserManager $userManager,
 			ICloudIdManager $cloudIdManager,
-			\OCP\GlobalScale\IConfig $globalScaleConfig,
-			CloudFederationProvider $cloudFederationProvider
+			\OCP\GlobalScale\IConfig $globalScaleConfig
 	) {
 		$this->dbConnection = $connection;
 		$this->addressHandler = $addressHandler;
@@ -136,8 +130,6 @@ class FederatedShareProvider implements IShareProvider {
 		$this->userManager = $userManager;
 		$this->cloudIdManager = $cloudIdManager;
 		$this->gsConfig = $globalScaleConfig;
-		$this->cloudFederationProvider = $cloudFederationProvider;
-
 	}
 
 	/**
diff --git a/apps/federatedfilesharing/lib/ocm/CloudFederationProvider.php b/apps/federatedfilesharing/lib/ocm/CloudFederationProvider.php
deleted file mode 100644
index 36b2d282b9..0000000000
--- a/apps/federatedfilesharing/lib/ocm/CloudFederationProvider.php
+++ /dev/null
@@ -1,83 +0,0 @@
-<?php
-/**
- * @copyright Copyright (c) 2018 Bjoern Schiessle <bjoern@schiessle.org>
- *
- * @license GNU AGPL version 3 or any later version
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-namespace OCA\FederatedFileSharing\OCM;
-
-use OCP\Federation\ICloudFederationFactory;
-use OCP\Federation\ICloudFederationProvider;
-use OCP\Federation\ICloudFederationShare;
-
-class CloudFederationProvider implements ICloudFederationProvider {
-
-	/** @var string */
-	private $shareType;
-
-	/**
-	 * CloudFederationProvider constructor.
-	 *
-	 * @param string $shareType
-	 */
-	public function __construct($shareType) {
-		$this->shareType = $shareType;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getShareType() {
-		return $this->shareType;
-	}
-
-	/**
-	 * send new share to another server
-	 *
-	 * @since 14.0.0
-	 */
-	public function sendShare() {
-		// TODO: Implement sendShare() method.
-	}
-
-	/**
-	 * share received from another server
-	 *
-	 * @param ICloudFederationShare $share
-	 * @return string provider specific unique ID of the share
-	 *
-	 * @since 14.0.0
-	 */
-	public function shareReceived(ICloudFederationShare $share) {
-		// TODO: Implement shareReceived() method.
-	}
-
-	/**
-	 * notification received from another server
-	 *
-	 * @param string $id unique ID of a already existing share
-	 * @param array $notification provider specific notification
-	 *
-	 * @throws \OCP\Federation\Exceptions\ShareNotFoundException
-	 *
-	 * @since 14.0.0
-	 */
-	public function notificationReceived($id, $notification) {
-		// TODO: Implement notificationReceived() method.
-	}
-}
diff --git a/apps/federatedfilesharing/lib/ocm/CloudFederationProviderFiles.php b/apps/federatedfilesharing/lib/ocm/CloudFederationProviderFiles.php
new file mode 100644
index 0000000000..f05f446914
--- /dev/null
+++ b/apps/federatedfilesharing/lib/ocm/CloudFederationProviderFiles.php
@@ -0,0 +1,272 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Bjoern Schiessle <bjoern@schiessle.org>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\FederatedFileSharing\OCM;
+
+use OC\AppFramework\Http;
+use OCA\Files_Sharing\Activity\Providers\RemoteShares;
+use OCA\FederatedFileSharing\AddressHandler;
+use OCA\FederatedFileSharing\FederatedShareProvider;
+use OCP\Activity\IManager as IActivityManager;
+use OCP\App\IAppManager;
+use OCP\Federation\Exceptions\ProviderCouldNotAddShareException;
+use OCP\Federation\ICloudFederationProvider;
+use OCP\Federation\ICloudFederationShare;
+use OCP\Federation\ICloudIdManager;
+use OCP\ILogger;
+use OCP\IURLGenerator;
+use OCP\IUserManager;
+use OCP\Notification\IManager as INotificationManager;
+
+class CloudFederationProviderFiles implements ICloudFederationProvider {
+
+	/** @var IAppManager */
+	private $appManager;
+
+	/** @var FederatedShareProvider */
+	private $federatedShareProvider;
+
+	/** @var AddressHandler */
+	private $addressHandler;
+
+	/** @var ILogger */
+	private $logger;
+
+	/** @var IUserManager */
+	private $userManager;
+
+	/** @var ICloudIdManager */
+	private $cloudIdManager;
+
+	/** @var IActivityManager */
+	private $activityManager;
+
+	/** @var INotificationManager */
+	private $notificationManager;
+
+	/** @var IURLGenerator */
+	private $urlGenerator;
+
+	/**
+	 * CloudFederationProvider constructor.
+	 *
+	 * @param IAppManager $appManager
+	 * @param FederatedShareProvider $federatedShareProvider
+	 * @param AddressHandler $addressHandler
+	 * @param ILogger $logger
+	 * @param IUserManager $userManager
+	 * @param ICloudIdManager $cloudIdManager
+	 * @param IActivityManager $activityManager
+	 * @param INotificationManager $notificationManager
+	 * @param IURLGenerator $urlGenerator
+	 */
+	public function __construct(IAppManager $appManager,
+								FederatedShareProvider $federatedShareProvider,
+								AddressHandler $addressHandler,
+								ILogger $logger,
+								IUserManager $userManager,
+								ICloudIdManager $cloudIdManager,
+								IActivityManager $activityManager,
+								INotificationManager $notificationManager,
+								IURLGenerator $urlGenerator
+	) {
+		$this->appManager = $appManager;
+		$this->federatedShareProvider = $federatedShareProvider;
+		$this->addressHandler = $addressHandler;
+		$this->logger = $logger;
+		$this->userManager = $userManager;
+		$this->cloudIdManager = $cloudIdManager;
+		$this->activityManager = $activityManager;
+		$this->notificationManager = $notificationManager;
+		$this->urlGenerator = $urlGenerator;
+	}
+
+
+
+	/**
+	 * @return string
+	 */
+	public function getShareType() {
+		return 'file';
+	}
+
+	/**
+	 * send new share to another server
+	 *
+	 * @since 14.0.0
+	 */
+	public function sendShare() {
+		// TODO: Implement sendShare() method.
+	}
+
+	/**
+	 * share received from another server
+	 *
+	 * @param ICloudFederationShare $share
+	 * @return string provider specific unique ID of the share
+	 *
+	 * @throws ProviderCouldNotAddShareException
+	 * @throws \OCP\AppFramework\QueryException
+	 * @throws \OC\HintException
+	 * @since 14.0.0
+	 */
+	public function shareReceived(ICloudFederationShare $share) {
+
+		if (!$this->isS2SEnabled(true)) {
+			throw new ProviderCouldNotAddShareException('Server does not support federated cloud sharing', '', Http::STATUS_SERVICE_UNAVAILABLE);
+		}
+
+		$protocol = $share->getProtocol();
+		if ($protocol['name'] !== 'webdav') {
+			throw new ProviderCouldNotAddShareException('Unsupported protocol for data exchange.', '', Http::STATUS_NOT_IMPLEMENTED);
+		}
+
+		list($ownerUid, $remote) = $this->addressHandler->splitUserRemote($share->getOwner());
+
+		$remote = $remote;
+		$token = isset($protocol['options']['access_token']) ? $protocol['options']['access_token'] : null;
+		$name = $share->getResourceName();
+		$owner = $share->getOwnerDisplayName();
+		$sharedBy = $share->getSharedByDisplayName();
+		$shareWith = $share->getShareWith();
+		$remoteId = $share->getProviderId();
+		$sharedByFederatedId = $share->getSharedBy();
+		$ownerFederatedId = $share->getOwner();
+
+		// if no explicit information about the person who created the share was send
+		// we assume that the share comes from the owner
+		if ($sharedByFederatedId === null) {
+			$sharedBy = $owner;
+			$sharedByFederatedId = $ownerFederatedId;
+		}
+
+		if ($remote && $token && $name && $owner && $remoteId && $shareWith) {
+
+			if (!\OCP\Util::isValidFileName($name)) {
+				throw new ProviderCouldNotAddShareException('The mountpoint name contains invalid characters.', '', Http::STATUS_BAD_REQUEST);
+			}
+
+			// FIXME this should be a method in the user management instead
+			$this->logger->debug('shareWith before, ' . $shareWith, ['app' => 'files_sharing']);
+			\OCP\Util::emitHook(
+				'\OCA\Files_Sharing\API\Server2Server',
+				'preLoginNameUsedAsUserName',
+				array('uid' => &$shareWith)
+			);
+			$this->logger->debug('shareWith after, ' . $shareWith, ['app' => 'files_sharing']);
+
+			if (!$this->userManager->userExists($shareWith)) {
+				throw new ProviderCouldNotAddShareException('User does not exists', '',Http::STATUS_BAD_REQUEST);
+			}
+
+			\OC_Util::setupFS($shareWith);
+
+			$externalManager = new \OCA\Files_Sharing\External\Manager(
+				\OC::$server->getDatabaseConnection(),
+				\OC\Files\Filesystem::getMountManager(),
+				\OC\Files\Filesystem::getLoader(),
+				\OC::$server->getHTTPClientService(),
+				\OC::$server->getNotificationManager(),
+				\OC::$server->query(\OCP\OCS\IDiscoveryService::class),
+				$shareWith
+			);
+
+			try {
+				$externalManager->addShare($remote, $token, '', $name, $owner, false, $shareWith, $remoteId);
+				$shareId = \OC::$server->getDatabaseConnection()->lastInsertId('*PREFIX*share_external');
+
+				$event = $this->activityManager->generateEvent();
+				$event->setApp('files_sharing')
+					->setType('remote_share')
+					->setSubject(RemoteShares::SUBJECT_REMOTE_SHARE_RECEIVED, [$ownerFederatedId, trim($name, '/')])
+					->setAffectedUser($shareWith)
+					->setObject('remote_share', (int)$shareId, $name);
+				\OC::$server->getActivityManager()->publish($event);
+
+				$notification = $this->notificationManager->createNotification();
+				$notification->setApp('files_sharing')
+					->setUser($shareWith)
+					->setDateTime(new \DateTime())
+					->setObject('remote_share', $shareId)
+					->setSubject('remote_share', [$ownerFederatedId, $sharedByFederatedId, trim($name, '/')]);
+
+				$declineAction = $notification->createAction();
+				$declineAction->setLabel('decline')
+					->setLink($this->urlGenerator->getAbsoluteURL($this->urlGenerator->linkTo('', 'ocs/v2.php/apps/files_sharing/api/v1/remote_shares/pending/' . $shareId)), 'DELETE');
+				$notification->addAction($declineAction);
+
+				$acceptAction = $notification->createAction();
+				$acceptAction->setLabel('accept')
+					->setLink($this->urlGenerator->getAbsoluteURL($this->urlGenerator->linkTo('', 'ocs/v2.php/apps/files_sharing/api/v1/remote_shares/pending/' . $shareId)), 'POST');
+				$notification->addAction($acceptAction);
+
+				$this->notificationManager->notify($notification);
+
+				return $shareId;
+			} catch (\Exception $e) {
+				$this->logger->logException($e, [
+					'message' => 'Server can not add remote share.',
+					'level' => \OCP\Util::ERROR,
+					'app' => 'files_sharing'
+				]);
+				throw new ProviderCouldNotAddShareException('internal server error, was not able to add share from ' . $remote, '', HTTP::STATUS_INTERNAL_SERVER_ERROR);
+			}
+		}
+
+		throw new ProviderCouldNotAddShareException('server can not add remote share, missing parameter', '', HTTP::STATUS_BAD_REQUEST);
+
+	}
+
+	/**
+	 * notification received from another server
+	 *
+	 * @param string $id unique ID of a already existing share
+	 * @param array $notification provider specific notification
+	 *
+	 * @throws \OCP\Federation\Exceptions\ShareNotFoundException
+	 *
+	 * @since 14.0.0
+	 */
+	public function notificationReceived($id, $notification) {
+		// TODO: Implement notificationReceived() method.
+	}
+
+	/**
+	 * check if server-to-server sharing is enabled
+	 *
+	 * @param bool $incoming
+	 * @return bool
+	 */
+	private function isS2SEnabled($incoming = false) {
+
+		$result = $this->appManager->isEnabledForUser('files_sharing');
+
+		if ($incoming) {
+			$result = $result && $this->federatedShareProvider->isIncomingServer2serverShareEnabled();
+		} else {
+			$result = $result && $this->federatedShareProvider->isOutgoingServer2serverShareEnabled();
+		}
+
+		return $result;
+	}
+
+
+}
diff --git a/lib/public/Federation/Exceptions/ProviderCouldNotAddShareException.php b/lib/public/Federation/Exceptions/ProviderCouldNotAddShareException.php
index b608437aa3..205206d5af 100644
--- a/lib/public/Federation/Exceptions/ProviderCouldNotAddShareException.php
+++ b/lib/public/Federation/Exceptions/ProviderCouldNotAddShareException.php
@@ -22,7 +22,13 @@
 namespace OCP\Federation\Exceptions;
 
 use OC\HintException;
+use OCP\AppFramework\Http;
 
 class ProviderCouldNotAddShareException extends HintException {
 
+	public function __construct($message, $hint = '', $code = Http::STATUS_BAD_REQUEST, \Exception $previous = null) {
+		parent::__construct($message, $hint, $code, $previous);
+	}
+
+
 }
diff --git a/lib/public/Federation/ICloudFederationProvider.php b/lib/public/Federation/ICloudFederationProvider.php
index 4c11fc2039..535f61aae8 100644
--- a/lib/public/Federation/ICloudFederationProvider.php
+++ b/lib/public/Federation/ICloudFederationProvider.php
@@ -21,6 +21,7 @@
 
 namespace OCP\Federation;
 
+use OCP\Federation\Exceptions\ProviderCouldNotAddShareException;
 use OCP\Federation\Exceptions\ShareNotFoundException;
 
 /**
@@ -35,17 +36,12 @@ use OCP\Federation\Exceptions\ShareNotFoundException;
 
 interface ICloudFederationProvider {
 
-	/**
-	 * ICloudFederationProvider constructor.
-	 *
-	 * @param $shareType define the share type, handled by this provider
-	 */
-	public function __construct($shareType);
-
 	/**
 	 * get the name of the share type, handled by this provider
 	 *
 	 * @return string
+	 *
+	 * @since 14.0.0
 	 */
 	public function getShareType();
 
@@ -62,6 +58,8 @@ interface ICloudFederationProvider {
 	 * @param ICloudFederationShare $share
 	 * @return string provider specific unique ID of the share
 	 *
+	 * @throws ProviderCouldNotAddShareException
+	 *
 	 * @since 14.0.0
 	 */
 	public function shareReceived(ICloudFederationShare $share);