diff --git a/packages/Keyguard/src/com/android/keyguard/KeyguardUpdateMonitor.java b/packages/Keyguard/src/com/android/keyguard/KeyguardUpdateMonitor.java
index a9f6dc9052b3a..4c8c0362cbf26 100644
--- a/packages/Keyguard/src/com/android/keyguard/KeyguardUpdateMonitor.java
+++ b/packages/Keyguard/src/com/android/keyguard/KeyguardUpdateMonitor.java
@@ -1625,7 +1625,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener {
      */
     public void reportSimUnlocked(int subId) {
         if (DEBUG_SIM_STATES) Log.v(TAG, "reportSimUnlocked(subId=" + subId + ")");
-        int slotId = SubscriptionManager.getSlotId(subId);
+        int slotId = SubscriptionManager.getSlotIndex(subId);
         handleSimStateChange(subId, slotId, State.READY);
     }
 
@@ -1794,7 +1794,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener {
         for (int i = 0; i < list.size(); i++) {
             final SubscriptionInfo info = list.get(i);
             final int id = info.getSubscriptionId();
-            int slotId = SubscriptionManager.getSlotId(id);
+            int slotId = SubscriptionManager.getSlotIndex(id);
             if (state == getSimState(id) && bestSlotId > slotId ) {
                 resultId = id;
                 bestSlotId = slotId;
diff --git a/telephony/java/android/telephony/PhoneNumberUtils.java b/telephony/java/android/telephony/PhoneNumberUtils.java
index 199a12ae70df3..bc5e4d51e0f8f 100644
--- a/telephony/java/android/telephony/PhoneNumberUtils.java
+++ b/telephony/java/android/telephony/PhoneNumberUtils.java
@@ -1897,7 +1897,7 @@ public class PhoneNumberUtils
         number = extractNetworkPortionAlt(number);
 
         String emergencyNumbers = "";
-        int slotId = SubscriptionManager.getSlotId(subId);
+        int slotId = SubscriptionManager.getSlotIndex(subId);
 
         // retrieve the list of emergency numbers
         // check read-write ecclist property first
diff --git a/telephony/java/android/telephony/SubscriptionManager.java b/telephony/java/android/telephony/SubscriptionManager.java
index dd6f9cb157b67..201f3ad5dce70 100644
--- a/telephony/java/android/telephony/SubscriptionManager.java
+++ b/telephony/java/android/telephony/SubscriptionManager.java
@@ -521,14 +521,14 @@ public class SubscriptionManager {
     }
 
     /**
-     * Get the active SubscriptionInfo associated with the slotIdx
-     * @param slotIdx the slot which the subscription is inserted
+     * Get the active SubscriptionInfo associated with the slotIndex
+     * @param slotIndex the slot which the subscription is inserted
      * @return SubscriptionInfo, maybe null if its not active
      */
-    public SubscriptionInfo getActiveSubscriptionInfoForSimSlotIndex(int slotIdx) {
-        if (VDBG) logd("[getActiveSubscriptionInfoForSimSlotIndex]+ slotIdx=" + slotIdx);
-        if (!isValidSlotId(slotIdx)) {
-            logd("[getActiveSubscriptionInfoForSimSlotIndex]- invalid slotIdx");
+    public SubscriptionInfo getActiveSubscriptionInfoForSimSlotIndex(int slotIndex) {
+        if (VDBG) logd("[getActiveSubscriptionInfoForSimSlotIndex]+ slotIndex=" + slotIndex);
+        if (!isValidSlotIndex(slotIndex)) {
+            logd("[getActiveSubscriptionInfoForSimSlotIndex]- invalid slotIndex");
             return null;
         }
 
@@ -537,7 +537,7 @@ public class SubscriptionManager {
         try {
             ISub iSub = ISub.Stub.asInterface(ServiceManager.getService("isub"));
             if (iSub != null) {
-                result = iSub.getActiveSubscriptionInfoForSimSlotIndex(slotIdx,
+                result = iSub.getActiveSubscriptionInfoForSimSlotIndex(slotIndex,
                         mContext.getOpPackageName());
             }
         } catch (RemoteException ex) {
@@ -671,24 +671,24 @@ public class SubscriptionManager {
     /**
      * Add a new SubscriptionInfo to SubscriptionInfo database if needed
      * @param iccId the IccId of the SIM card
-     * @param slotId the slot which the SIM is inserted
+     * @param slotIndex the slot which the SIM is inserted
      * @return the URL of the newly created row or the updated row
      * @hide
      */
-    public Uri addSubscriptionInfoRecord(String iccId, int slotId) {
-        if (VDBG) logd("[addSubscriptionInfoRecord]+ iccId:" + iccId + " slotId:" + slotId);
+    public Uri addSubscriptionInfoRecord(String iccId, int slotIndex) {
+        if (VDBG) logd("[addSubscriptionInfoRecord]+ iccId:" + iccId + " slotIndex:" + slotIndex);
         if (iccId == null) {
             logd("[addSubscriptionInfoRecord]- null iccId");
         }
-        if (!isValidSlotId(slotId)) {
-            logd("[addSubscriptionInfoRecord]- invalid slotId");
+        if (!isValidSlotIndex(slotIndex)) {
+            logd("[addSubscriptionInfoRecord]- invalid slotIndex");
         }
 
         try {
             ISub iSub = ISub.Stub.asInterface(ServiceManager.getService("isub"));
             if (iSub != null) {
                 // FIXME: This returns 1 on success, 0 on error should should we return it?
-                iSub.addSubInfoRecord(iccId, slotId);
+                iSub.addSubInfoRecord(iccId, slotIndex);
             }
         } catch (RemoteException ex) {
             // ignore it
@@ -830,15 +830,15 @@ public class SubscriptionManager {
     }
 
     /**
-     * Get slotId associated with the subscription.
-     * @return slotId as a positive integer or a negative value if an error either
+     * Get slotIndex associated with the subscription.
+     * @return slotIndex as a positive integer or a negative value if an error either
      * SIM_NOT_INSERTED or < 0 if an invalid slot index
      * @hide
      */
-    public static int getSlotId(int subId) {
+    public static int getSlotIndex(int subId) {
         if (!isValidSubscriptionId(subId)) {
             if (DBG) {
-                logd("[getSlotId]- fail");
+                logd("[getSlotIndex]- fail");
             }
         }
 
@@ -847,7 +847,7 @@ public class SubscriptionManager {
         try {
             ISub iSub = ISub.Stub.asInterface(ServiceManager.getService("isub"));
             if (iSub != null) {
-                result = iSub.getSlotId(subId);
+                result = iSub.getSlotIndex(subId);
             }
         } catch (RemoteException ex) {
             // ignore it
@@ -858,8 +858,8 @@ public class SubscriptionManager {
     }
 
     /** @hide */
-    public static int[] getSubId(int slotId) {
-        if (!isValidSlotId(slotId)) {
+    public static int[] getSubId(int slotIndex) {
+        if (!isValidSlotIndex(slotIndex)) {
             logd("[getSubId]- fail");
             return null;
         }
@@ -869,7 +869,7 @@ public class SubscriptionManager {
         try {
             ISub iSub = ISub.Stub.asInterface(ServiceManager.getService("isub"));
             if (iSub != null) {
-                subId = iSub.getSubId(slotId);
+                subId = iSub.getSubId(slotIndex);
             }
         } catch (RemoteException ex) {
             // ignore it
@@ -1155,8 +1155,8 @@ public class SubscriptionManager {
     }
 
     /** @hide */
-    public static boolean isValidSlotId(int slotId) {
-        return slotId >= 0 && slotId < TelephonyManager.getDefault().getSimCount();
+    public static boolean isValidSlotIndex(int slotIndex) {
+        return slotIndex >= 0 && slotIndex < TelephonyManager.getDefault().getSimCount();
     }
 
     /** @hide */
@@ -1179,7 +1179,7 @@ public class SubscriptionManager {
         if (VDBG) logd("putPhoneIdAndSubIdExtra: phoneId=" + phoneId + " subId=" + subId);
         intent.putExtra(PhoneConstants.SUBSCRIPTION_KEY, subId);
         intent.putExtra(PhoneConstants.PHONE_KEY, phoneId);
-        //FIXME this is using phoneId and slotId interchangeably
+        //FIXME this is using phoneId and slotIndex interchangeably
         //Eventually, this should be removed as it is not the slot id
         intent.putExtra(PhoneConstants.SLOT_KEY, phoneId);
     }
@@ -1228,9 +1228,9 @@ public class SubscriptionManager {
     }
 
     /**
-     * Returns a constant indicating the state of sim for the slot idx.
+     * Returns a constant indicating the state of sim for the slot index.
      *
-     * @param slotIdx
+     * @param slotIndex
      *
      * {@See TelephonyManager#SIM_STATE_UNKNOWN}
      * {@See TelephonyManager#SIM_STATE_ABSENT}
@@ -1244,13 +1244,13 @@ public class SubscriptionManager {
      *
      * {@hide}
      */
-    public static int getSimStateForSlotIdx(int slotIdx) {
+    public static int getSimStateForSlotIndex(int slotIndex) {
         int simState = TelephonyManager.SIM_STATE_UNKNOWN;
 
         try {
             ISub iSub = ISub.Stub.asInterface(ServiceManager.getService("isub"));
             if (iSub != null) {
-                simState = iSub.getSimStateForSlotIdx(slotIdx);
+                simState = iSub.getSimStateForSlotIndex(slotIndex);
             }
         } catch (RemoteException ex) {
         }
diff --git a/telephony/java/android/telephony/TelephonyManager.java b/telephony/java/android/telephony/TelephonyManager.java
index d0eb2f77d1453..a4182383175c1 100644
--- a/telephony/java/android/telephony/TelephonyManager.java
+++ b/telephony/java/android/telephony/TelephonyManager.java
@@ -863,15 +863,15 @@ public class TelephonyManager {
      * <p>Requires Permission:
      *   {@link android.Manifest.permission#READ_PHONE_STATE READ_PHONE_STATE}
      *
-     * @param slotId of which deviceID is returned
+     * @param slotIndex of which deviceID is returned
      */
     /** {@hide} */
-    public String getDeviceSoftwareVersion(int slotId) {
+    public String getDeviceSoftwareVersion(int slotIndex) {
         ITelephony telephony = getITelephony();
         if (telephony == null) return null;
 
         try {
-            return telephony.getDeviceSoftwareVersionForSlot(slotId, getOpPackageName());
+            return telephony.getDeviceSoftwareVersionForSlot(slotIndex, getOpPackageName());
         } catch (RemoteException ex) {
             return null;
         } catch (NullPointerException ex) {
@@ -906,15 +906,15 @@ public class TelephonyManager {
      * <p>Requires Permission:
      *   {@link android.Manifest.permission#READ_PHONE_STATE READ_PHONE_STATE}
      *
-     * @param slotId of which deviceID is returned
+     * @param slotIndex of which deviceID is returned
      */
-    public String getDeviceId(int slotId) {
-        // FIXME this assumes phoneId == slotId
+    public String getDeviceId(int slotIndex) {
+        // FIXME this assumes phoneId == slotIndex
         try {
             IPhoneSubInfo info = getSubscriberInfo();
             if (info == null)
                 return null;
-            return info.getDeviceIdForPhone(slotId, mContext.getOpPackageName());
+            return info.getDeviceIdForPhone(slotIndex, mContext.getOpPackageName());
         } catch (RemoteException ex) {
             return null;
         } catch (NullPointerException ex) {
@@ -941,17 +941,17 @@ public class TelephonyManager {
      * <p>Requires Permission:
      *   {@link android.Manifest.permission#READ_PHONE_STATE READ_PHONE_STATE}
      *
-     * @param slotId of which deviceID is returned
+     * @param slotIndex of which deviceID is returned
      *
      * @hide
      */
     @SystemApi
-    public String getImei(int slotId) {
+    public String getImei(int slotIndex) {
         ITelephony telephony = getITelephony();
         if (telephony == null) return null;
 
         try {
-            return telephony.getImeiForSlot(slotId, getOpPackageName());
+            return telephony.getImeiForSlot(slotIndex, getOpPackageName());
         } catch (RemoteException ex) {
             return null;
         } catch (NullPointerException ex) {
@@ -971,11 +971,11 @@ public class TelephonyManager {
     /**
      * Returns the NAI. Return null if NAI is not available.
      *
-     *  @param slotId of which Nai is returned
+     *  @param slotIndex of which Nai is returned
      */
     /** {@hide}*/
-    public String getNai(int slotId) {
-        int[] subId = SubscriptionManager.getSubId(slotId);
+    public String getNai(int slotIndex) {
+        int[] subId = SubscriptionManager.getSubId(slotIndex);
         try {
             IPhoneSubInfo info = getSubscriberInfo();
             if (info == null)
@@ -1171,23 +1171,23 @@ public class TelephonyManager {
      *
      * @hide
      */
-    public int getCurrentPhoneTypeForSlot(int slotId) {
+    public int getCurrentPhoneTypeForSlot(int slotIndex) {
         try{
             ITelephony telephony = getITelephony();
             if (telephony != null) {
-                return telephony.getActivePhoneTypeForSlot(slotId);
+                return telephony.getActivePhoneTypeForSlot(slotIndex);
             } else {
                 // This can happen when the ITelephony interface is not up yet.
-                return getPhoneTypeFromProperty(slotId);
+                return getPhoneTypeFromProperty(slotIndex);
             }
         } catch (RemoteException ex) {
             // This shouldn't happen in the normal case, as a backup we
             // read from the system property.
-            return getPhoneTypeFromProperty(slotId);
+            return getPhoneTypeFromProperty(slotIndex);
         } catch (NullPointerException ex) {
             // This shouldn't happen in the normal case, as a backup we
             // read from the system property.
-            return getPhoneTypeFromProperty(slotId);
+            return getPhoneTypeFromProperty(slotIndex);
         }
     }
 
@@ -1901,17 +1901,17 @@ public class TelephonyManager {
     /**
      * @return true if a ICC card is present for a subscription
      *
-     * @param slotId for which icc card presence is checked
+     * @param slotIndex for which icc card presence is checked
      */
     /** {@hide} */
-    // FIXME Input argument slotId should be of type int
-    public boolean hasIccCard(int slotId) {
+    // FIXME Input argument slotIndex should be of type int
+    public boolean hasIccCard(int slotIndex) {
 
         try {
             ITelephony telephony = getITelephony();
             if (telephony == null)
                 return false;
-            return telephony.hasIccCardUsingSlotId(slotId);
+            return telephony.hasIccCardUsingSlotIndex(slotIndex);
         } catch (RemoteException ex) {
             // Assume no ICC card if remote exception which shouldn't happen
             return false;
@@ -1936,31 +1936,31 @@ public class TelephonyManager {
      * @see #SIM_STATE_CARD_RESTRICTED
      */
     public int getSimState() {
-        int slotIdx = getDefaultSim();
-        // slotIdx may be invalid due to sim being absent. In that case query all slots to get
+        int slotIndex = getDefaultSim();
+        // slotIndex may be invalid due to sim being absent. In that case query all slots to get
         // sim state
-        if (slotIdx < 0) {
+        if (slotIndex < 0) {
             // query for all slots and return absent if all sim states are absent, otherwise
             // return unknown
             for (int i = 0; i < getPhoneCount(); i++) {
                 int simState = getSimState(i);
                 if (simState != SIM_STATE_ABSENT) {
-                    Rlog.d(TAG, "getSimState: default sim:" + slotIdx + ", sim state for " +
-                            "slotIdx=" + i + " is " + simState + ", return state as unknown");
+                    Rlog.d(TAG, "getSimState: default sim:" + slotIndex + ", sim state for " +
+                            "slotIndex=" + i + " is " + simState + ", return state as unknown");
                     return SIM_STATE_UNKNOWN;
                 }
             }
-            Rlog.d(TAG, "getSimState: default sim:" + slotIdx + ", all SIMs absent, return " +
+            Rlog.d(TAG, "getSimState: default sim:" + slotIndex + ", all SIMs absent, return " +
                     "state as absent");
             return SIM_STATE_ABSENT;
         }
-        return getSimState(slotIdx);
+        return getSimState(slotIndex);
     }
 
     /**
      * Returns a constant indicating the state of the device SIM card in a slot.
      *
-     * @param slotIdx
+     * @param slotIndex
      *
      * @see #SIM_STATE_UNKNOWN
      * @see #SIM_STATE_ABSENT
@@ -1973,8 +1973,8 @@ public class TelephonyManager {
      * @see #SIM_STATE_CARD_IO_ERROR
      * @see #SIM_STATE_CARD_RESTRICTED
      */
-    public int getSimState(int slotIdx) {
-        int simState = SubscriptionManager.getSimStateForSlotIdx(slotIdx);
+    public int getSimState(int slotIndex) {
+        int simState = SubscriptionManager.getSimStateForSlotIndex(slotIndex);
         return simState;
     }
 
@@ -3066,12 +3066,12 @@ public class TelephonyManager {
      *
      * @hide
      */
-    public int getCallStateForSlot(int slotId) {
+    public int getCallStateForSlot(int slotIndex) {
         try {
             ITelephony telephony = getITelephony();
             if (telephony == null)
                 return CALL_STATE_IDLE;
-            return telephony.getCallStateForSlot(slotId);
+            return telephony.getCallStateForSlot(slotIndex);
         } catch (RemoteException ex) {
             // the phone process is restarting.
             return CALL_STATE_IDLE;
@@ -3889,7 +3889,7 @@ public class TelephonyManager {
 
     /** {@hide} */
     public int getDefaultSim() {
-        return SubscriptionManager.getSlotId(SubscriptionManager.getDefaultSubscriptionId());
+        return SubscriptionManager.getSlotIndex(SubscriptionManager.getDefaultSubscriptionId());
     }
 
     /**
@@ -4254,7 +4254,7 @@ public class TelephonyManager {
      * feature or {@link null} if the service is not available. If an ImsServiceController is
      * available, the {@link IImsServiceFeatureListener} callback is registered as a listener for
      * feature updates.
-     * @param slotId The SIM slot that we are requesting the {@link IImsServiceController} for.
+     * @param slotIndex The SIM slot that we are requesting the {@link IImsServiceController} for.
      * @param feature The IMS Feature we are requesting, corresponding to {@link ImsFeature}.
      * @param callback Listener that will send updates to ImsManager when there are updates to
      * ImsServiceController.
@@ -4262,12 +4262,12 @@ public class TelephonyManager {
      * it is unavailable.
      * @hide
      */
-    public IImsServiceController getImsServiceControllerAndListen(int slotId, @Feature int feature,
+    public IImsServiceController getImsServiceControllerAndListen(int slotIndex, @Feature int feature,
             IImsServiceFeatureListener callback) {
         try {
             ITelephony telephony = getITelephony();
             if (telephony != null) {
-                return telephony.getImsServiceControllerAndListen(slotId, feature, callback);
+                return telephony.getImsServiceControllerAndListen(slotIndex, feature, callback);
             }
         } catch (RemoteException e) {
             Rlog.e(TAG, "getImsServiceControllerAndListen, RemoteException: " + e.getMessage());
@@ -5405,7 +5405,7 @@ public class TelephonyManager {
     /**
      * Set SIM card power state. Request is equivalent to inserting or removing the card.
      *
-     * @param slotId SIM slot id
+     * @param slotIndex SIM slot id
      * @param powerUp True if powering up the SIM, otherwise powering down
      *
      * <p>Requires Permission:
@@ -5413,11 +5413,11 @@ public class TelephonyManager {
      *
      * @hide
      **/
-    public void setSimPowerStateForSlot(int slotId, boolean powerUp) {
+    public void setSimPowerStateForSlot(int slotIndex, boolean powerUp) {
         try {
             ITelephony telephony = getITelephony();
             if (telephony != null) {
-                telephony.setSimPowerStateForSlot(slotId, powerUp);
+                telephony.setSimPowerStateForSlot(slotIndex, powerUp);
             }
         } catch (RemoteException e) {
             Log.e(TAG, "Error calling ITelephony#setSimPowerStateForSlot", e);
@@ -5953,7 +5953,7 @@ public class TelephonyManager {
     }
 
     /**
-     * Set the allowed carrier list for slotId
+     * Set the allowed carrier list for slotIndex
      * Require system privileges. In the future we may add this to carrier APIs.
      *
      * <p>Requires Permission:
@@ -5967,11 +5967,11 @@ public class TelephonyManager {
      * @hide
      */
     @SystemApi
-    public int setAllowedCarriers(int slotId, List<CarrierIdentifier> carriers) {
+    public int setAllowedCarriers(int slotIndex, List<CarrierIdentifier> carriers) {
         try {
             ITelephony service = getITelephony();
             if (service != null) {
-                return service.setAllowedCarriers(slotId, carriers);
+                return service.setAllowedCarriers(slotIndex, carriers);
             }
         } catch (RemoteException e) {
             Log.e(TAG, "Error calling ITelephony#setAllowedCarriers", e);
@@ -5982,7 +5982,7 @@ public class TelephonyManager {
     }
 
     /**
-     * Get the allowed carrier list for slotId.
+     * Get the allowed carrier list for slotIndex.
      * Require system privileges. In the future we may add this to carrier APIs.
      *
      * <p>Requires Permission:
@@ -5996,11 +5996,11 @@ public class TelephonyManager {
      * @hide
      */
     @SystemApi
-    public List<CarrierIdentifier> getAllowedCarriers(int slotId) {
+    public List<CarrierIdentifier> getAllowedCarriers(int slotIndex) {
         try {
             ITelephony service = getITelephony();
             if (service != null) {
-                return service.getAllowedCarriers(slotId);
+                return service.getAllowedCarriers(slotIndex);
             }
         } catch (RemoteException e) {
             Log.e(TAG, "Error calling ITelephony#getAllowedCarriers", e);
diff --git a/telephony/java/com/android/internal/telephony/ISub.aidl b/telephony/java/com/android/internal/telephony/ISub.aidl
index f6aef0859e906..71f2c6b80927c 100755
--- a/telephony/java/com/android/internal/telephony/ISub.aidl
+++ b/telephony/java/com/android/internal/telephony/ISub.aidl
@@ -52,12 +52,12 @@ interface ISub {
     SubscriptionInfo getActiveSubscriptionInfoForIccId(String iccId, String callingPackage);
 
     /**
-     * Get the active SubscriptionInfo associated with the slotIdx
-     * @param slotIdx the slot which the subscription is inserted
+     * Get the active SubscriptionInfo associated with the slotIndex
+     * @param slotIndex the slot which the subscription is inserted
      * @param callingPackage The package maing the call.
      * @return SubscriptionInfo, maybe null if its not active
      */
-    SubscriptionInfo getActiveSubscriptionInfoForSimSlotIndex(int slotIdx, String callingPackage);
+    SubscriptionInfo getActiveSubscriptionInfoForSimSlotIndex(int slotIndex, String callingPackage);
 
     /**
      * Get the SubscriptionInfo(s) of the active subscriptions. The records will be sorted
@@ -96,10 +96,10 @@ interface ISub {
     /**
      * Add a new SubscriptionInfo to subinfo database if needed
      * @param iccId the IccId of the SIM card
-     * @param slotId the slot which the SIM is inserted
+     * @param slotIndex the slot which the SIM is inserted
      * @return the URL of the newly created row or the updated row
      */
-    int addSubInfoRecord(String iccId, int slotId);
+    int addSubInfoRecord(String iccId, int slotIndex);
 
     /**
      * Set SIM icon tint color by simInfo index
@@ -142,9 +142,9 @@ interface ISub {
      */
     int setDataRoaming(int roaming, int subId);
 
-    int getSlotId(int subId);
+    int getSlotIndex(int subId);
 
-    int[] getSubId(int slotId);
+    int[] getSubId(int slotIndex);
 
     int getDefaultSubId();
 
@@ -177,10 +177,10 @@ interface ISub {
     String getSubscriptionProperty(int subId, String propKey, String callingPackage);
 
     /**
-     * Get the SIM state for the slot idx
+     * Get the SIM state for the slot index
      * @return SIM state as the ordinal of IccCardConstants.State
      */
-    int getSimStateForSlotIdx(int slotIdx);
+    int getSimStateForSlotIndex(int slotIndex);
 
     boolean isActiveSubId(int subId);
 }
diff --git a/telephony/java/com/android/internal/telephony/ITelephony.aidl b/telephony/java/com/android/internal/telephony/ITelephony.aidl
index d21efc6e091a8..3a99cb98b97b5 100644
--- a/telephony/java/com/android/internal/telephony/ITelephony.aidl
+++ b/telephony/java/com/android/internal/telephony/ITelephony.aidl
@@ -370,7 +370,7 @@ interface ITelephony {
     /**
      * Returns the call state for a slot.
      */
-     int getCallStateForSlot(int slotId);
+     int getCallStateForSlot(int slotIndex);
 
      int getDataActivity();
      int getDataState();
@@ -386,9 +386,9 @@ interface ITelephony {
      * Returns the current active phone type as integer for particular slot.
      * Returns TelephonyManager.PHONE_TYPE_CDMA if RILConstants.CDMA_PHONE
      * and TelephonyManager.PHONE_TYPE_GSM if RILConstants.GSM_PHONE
-     * @param slotId - slot to query.
+     * @param slotIndex - slot to query.
      */
-    int getActivePhoneTypeForSlot(int slotId);
+    int getActivePhoneTypeForSlot(int slotIndex);
 
     /**
      * Returns the CDMA ERI icon index to display
@@ -542,10 +542,10 @@ interface ITelephony {
 
     /**
      * Return true if an ICC card is present for a subId.
-     * @param slotId user preferred slotId.
+     * @param slotIndex user preferred slotIndex.
      * Return true if an ICC card is present
      */
-    boolean hasIccCardUsingSlotId(int slotId);
+    boolean hasIccCardUsingSlotIndex(int slotIndex);
 
     /**
      * Return if the current radio is LTE on CDMA. This
@@ -746,7 +746,7 @@ interface ITelephony {
      *  requested as well as registering the ImsServiceController for callbacks using the
      *  IImsServiceFeatureListener interface.
      */
-    IImsServiceController getImsServiceControllerAndListen(int slotId, int feature,
+    IImsServiceController getImsServiceControllerAndListen(int slotIndex, int feature,
                 IImsServiceFeatureListener callback);
 
     /**
@@ -1054,22 +1054,22 @@ interface ITelephony {
     /**
      * Returns the IMEI for the given slot.
      *
-     * @param slotId - device slot.
+     * @param slotIndex - device slot.
      * @param callingPackage The package making the call.
      * <p>Requires Permission:
      *   {@link android.Manifest.permission#READ_PHONE_STATE READ_PHONE_STATE}
      */
-    String getImeiForSlot(int slotId, String callingPackage);
+    String getImeiForSlot(int slotIndex, String callingPackage);
 
     /**
      * Returns the device software version.
      *
-     * @param slotId - device slot.
+     * @param slotIndex - device slot.
      * @param callingPackage The package making the call.
      * <p>Requires Permission:
      *   {@link android.Manifest.permission#READ_PHONE_STATE READ_PHONE_STATE}
      */
-    String getDeviceSoftwareVersionForSlot(int slotId, String callingPackage);
+    String getDeviceSoftwareVersionForSlot(int slotIndex, String callingPackage);
 
     /**
      * Returns the subscription ID associated with the specified PhoneAccount.
@@ -1167,22 +1167,22 @@ interface ITelephony {
     List<TelephonyHistogram> getTelephonyHistograms();
 
     /**
-     * Set the allowed carrier list for slotId
+     * Set the allowed carrier list for slotIndex
      * Require system privileges. In the future we may add this to carrier APIs.
      *
      * @return The number of carriers set successfully. Should match length of
      * carriers on success.
      */
-    int setAllowedCarriers(int slotId, in List<CarrierIdentifier> carriers);
+    int setAllowedCarriers(int slotIndex, in List<CarrierIdentifier> carriers);
 
     /**
-     * Get the allowed carrier list for slotId.
+     * Get the allowed carrier list for slotIndex.
      * Require system privileges. In the future we may add this to carrier APIs.
      *
      * @return List of {@link android.service.carrier.CarrierIdentifier}; empty list
      * means all carriers are allowed.
      */
-    List<CarrierIdentifier> getAllowedCarriers(int slotId);
+    List<CarrierIdentifier> getAllowedCarriers(int slotIndex);
 
     /**
      * Action set from carrier signalling broadcast receivers to enable/disable metered apns
@@ -1229,11 +1229,11 @@ interface ITelephony {
 
     /**
      * Set SIM card power state. Request is equivalent to inserting or removing the card.
-     * @param slotId SIM slot id
+     * @param slotIndex SIM slot id
      * @param powerUp True if powering up the SIM, otherwise powering down
      * @hide
      * */
-    void setSimPowerStateForSlot(int slotId, boolean powerUp);
+    void setSimPowerStateForSlot(int slotIndex, boolean powerUp);
 
     /**
      * Returns a list of Forbidden PLMNs from the specified SIM App