diff --git a/rw_core/core/device/state_transitions.go b/rw_core/core/device/state_transitions.go
new file mode 100644
index 0000000..f7be154
--- /dev/null
+++ b/rw_core/core/device/state_transitions.go
@@ -0,0 +1,338 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+
+ * http://www.apache.org/licenses/LICENSE-2.0
+
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package device
+
+import (
+	"context"
+	"github.com/opencord/voltha-go/rw_core/coreif"
+	"github.com/opencord/voltha-protos/v3/go/voltha"
+)
+
+// deviceType mentions type of device like parent, child
+type deviceType int32
+
+const (
+	parent deviceType = 0
+	child  deviceType = 1
+	any    deviceType = 2
+)
+
+type matchResult uint8
+
+const (
+	noMatch            matchResult = iota // current state has not match in the transition table
+	currWildcardMatch                     // current state matches the wildcard *_UNKNOWN state in the transition table
+	currStateOnlyMatch                    // current state matches the current state and previous state matches the wildcard in the transition table
+	currPrevStateMatch                    // both current and previous states match in the transition table
+)
+
+// match is used to keep the current match states
+type match struct {
+	admin, oper, conn matchResult
+}
+
+// toInt returns an integer representing the matching level of the match (the larger the number the better)
+func (m *match) toInt() int {
+	return int(m.admin<<4 | m.oper<<2 | m.conn)
+}
+
+// isExactMatch returns true if match is an exact match
+func (m *match) isExactMatch() bool {
+	return m.admin == currPrevStateMatch && m.oper == currPrevStateMatch && m.conn == currPrevStateMatch
+}
+
+// isBetterMatch returns true if newMatch is a worse match
+func (m *match) isBetterMatch(newMatch *match) bool {
+	return m.toInt() > newMatch.toInt()
+}
+
+// deviceState has admin, operational and connection status of device
+type deviceState struct {
+	Admin       voltha.AdminState_Types
+	Connection  voltha.ConnectStatus_Types
+	Operational voltha.OperStatus_Types
+}
+
+// TransitionHandler function type which takes the current and previous device info as input parameter
+type TransitionHandler func(context.Context, *voltha.Device) error
+
+// Transition represent transition related attributes
+type Transition struct {
+	deviceType    deviceType
+	previousState deviceState
+	currentState  deviceState
+	handlers      []TransitionHandler
+}
+
+// TransitionMap represent map of transitions and device manager
+type TransitionMap struct {
+	transitions []Transition
+	dMgr        coreif.DeviceManager
+}
+
+// NewTransitionMap creates transition map
+func NewTransitionMap(dMgr coreif.DeviceManager) *TransitionMap {
+	var transitionMap TransitionMap
+	transitionMap.dMgr = dMgr
+	transitionMap.transitions = make([]Transition, 0)
+	transitionMap.transitions = append(
+		transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVE},
+			handlers:      []TransitionHandler{dMgr.CreateLogicalDevice}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_DISCOVERED},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			handlers:      []TransitionHandler{}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_DISCOVERED},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVE},
+			handlers:      []TransitionHandler{dMgr.SetupUNILogicalPorts}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_DISCOVERED},
+			handlers:      []TransitionHandler{}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVE},
+			handlers:      []TransitionHandler{dMgr.SetupUNILogicalPorts}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_PREPROVISIONED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DELETED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.RunPostDeviceDelete}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_UNKNOWN, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DELETED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.DisableAllChildDevices, dMgr.DeleteAllUNILogicalPorts, dMgr.DeleteAllChildDevices, dMgr.DeleteAllLogicalPorts, dMgr.DeleteLogicalDevice, dMgr.RunPostDeviceDelete}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_REACHABLE, Operational: voltha.OperStatus_ACTIVE},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNREACHABLE, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.DeleteAllLogicalPorts, dMgr.DeleteLogicalDevice, dMgr.DeleteAllChildDevices, dMgr.DeleteAllDeviceFlows}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_REACHABLE, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_UNREACHABLE, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.DeleteAllLogicalPorts, dMgr.DeleteLogicalDevice, dMgr.DeleteAllChildDevices, dMgr.DeleteAllDeviceFlows}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNREACHABLE, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_REACHABLE, Operational: voltha.OperStatus_ACTIVE},
+			handlers:      []TransitionHandler{dMgr.CreateLogicalDevice}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_UNREACHABLE, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_REACHABLE, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.CreateLogicalDevice}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_UNKNOWN, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DELETED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.ChildDeviceLost, dMgr.DeleteLogicalPorts, dMgr.RunPostDeviceDelete}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DELETED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.ChildDeviceLost, dMgr.DeleteLogicalPorts, dMgr.RunPostDeviceDelete}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVE},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_PREPROVISIONED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_UNKNOWN, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DOWNLOADING_IMAGE, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_UNKNOWN, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    parent,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVE},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_ACTIVATING},
+			currentState:  deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_ENABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_PREPROVISIONED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    child,
+			previousState: deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_UNKNOWN, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_PREPROVISIONED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+	transitionMap.transitions = append(transitionMap.transitions,
+		Transition{
+			deviceType:    any,
+			previousState: deviceState{Admin: voltha.AdminState_DOWNLOADING_IMAGE, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			currentState:  deviceState{Admin: voltha.AdminState_DISABLED, Connection: voltha.ConnectStatus_UNKNOWN, Operational: voltha.OperStatus_UNKNOWN},
+			handlers:      []TransitionHandler{dMgr.NotifyInvalidTransition}})
+
+	return &transitionMap
+}
+
+func getDeviceStates(device *voltha.Device) *deviceState {
+	return &deviceState{Admin: device.AdminState, Connection: device.ConnectStatus, Operational: device.OperStatus}
+}
+
+// isMatched matches a state transition.  It returns whether there is a match and if there is whether it is an exact match
+func getHandler(previous *deviceState, current *deviceState, transition *Transition) ([]TransitionHandler, *match) {
+	m := &match{}
+	// Do we have an exact match?
+	if *previous == transition.previousState && *current == transition.currentState {
+		return transition.handlers, &match{admin: currPrevStateMatch, oper: currPrevStateMatch, conn: currPrevStateMatch}
+	}
+
+	// Do we have Admin state match?
+	if current.Admin == transition.currentState.Admin && transition.currentState.Admin != voltha.AdminState_UNKNOWN {
+		if previous.Admin == transition.previousState.Admin {
+			m.admin = currPrevStateMatch
+		} else if transition.previousState.Admin == voltha.AdminState_UNKNOWN {
+			m.admin = currStateOnlyMatch
+		}
+	} else if current.Admin == transition.currentState.Admin && transition.currentState.Admin == voltha.AdminState_UNKNOWN {
+		if previous.Admin == transition.previousState.Admin || transition.previousState.Admin == voltha.AdminState_UNKNOWN {
+			m.admin = currWildcardMatch
+		}
+	}
+	if m.admin == noMatch {
+		// invalid transition - need to match on current admin state
+		return nil, m
+	}
+
+	// Do we have an operational state match?
+	if current.Operational == transition.currentState.Operational && transition.previousState.Operational != voltha.OperStatus_UNKNOWN {
+		if previous.Operational == transition.previousState.Operational || transition.previousState.Operational == voltha.OperStatus_UNKNOWN {
+			m.oper = currPrevStateMatch
+		} else {
+			m.oper = currStateOnlyMatch
+		}
+	} else if current.Operational == transition.currentState.Operational && transition.previousState.Operational == voltha.OperStatus_UNKNOWN {
+		if previous.Operational == transition.previousState.Operational || transition.previousState.Operational == voltha.OperStatus_UNKNOWN {
+			m.oper = currWildcardMatch
+		}
+	}
+
+	// Do we have an connection state match?
+	if current.Connection == transition.currentState.Connection && transition.previousState.Connection != voltha.ConnectStatus_UNKNOWN {
+		if previous.Connection == transition.previousState.Connection || transition.previousState.Connection == voltha.ConnectStatus_UNKNOWN {
+			m.conn = currPrevStateMatch
+		} else {
+			m.conn = currStateOnlyMatch
+		}
+	} else if current.Connection == transition.currentState.Connection && transition.previousState.Connection == voltha.ConnectStatus_UNKNOWN {
+		if previous.Connection == transition.previousState.Connection || transition.previousState.Connection == voltha.ConnectStatus_UNKNOWN {
+			m.conn = currWildcardMatch
+		}
+	}
+
+	return transition.handlers, m
+}
+
+// GetTransitionHandler returns transition handler & a flag that's set if the transition is invalid
+func (tMap *TransitionMap) GetTransitionHandler(device *voltha.Device, pState *deviceState) []TransitionHandler {
+	//1. Get the previous and current set of states
+	cState := getDeviceStates(device)
+
+	// Do nothing is there are no states change
+	if *pState == *cState {
+		return nil
+	}
+
+	//logger.Infow("deviceType", log.Fields{"device": pDevice})
+	deviceType := parent
+	if !device.Root {
+		logger.Info("device is child")
+		deviceType = child
+	}
+	logger.Infof("deviceType:%d-deviceId:%s-previous:%v-current:%v", deviceType, device.Id, pState, cState)
+
+	//2. Go over transition array to get the right transition
+	var currentMatch []TransitionHandler
+	var tempHandler []TransitionHandler
+	var m *match
+	bestMatch := &match{}
+	for _, aTransition := range tMap.transitions {
+		// consider transition only if it matches deviceType or is a wild card - any
+		if aTransition.deviceType != deviceType && aTransition.deviceType != any {
+			continue
+		}
+		tempHandler, m = getHandler(pState, cState, &aTransition)
+		if tempHandler != nil {
+			if m.isExactMatch() && aTransition.deviceType == deviceType {
+				return tempHandler
+			} else if m.isExactMatch() || m.isBetterMatch(bestMatch) {
+				currentMatch = tempHandler
+				bestMatch = m
+			}
+		}
+	}
+	return currentMatch
+}