RRC Connection Establishment, Re-Establishment, and Resumption in a Wireless Communication System

Abstract

A wireless device ( 14 ) transmits, to a radio network node ( 12 ), a radio resource control (RRC) connection request ( 18 ) that requests the establishment, re-establishment, or resumption of an RRC connection ( 16 ). The RRC connection request ( 18 ) indicates a type of core network to which the wireless device ( 14 )selects to connect. The wireless device ( 14 ) in some embodiments receives a response to the RRC connection request ( 18 ), based on the type of core network to which the wireless device ( 14 ) selects to connect. For example, the wireless device ( 14 ) may receive the response using a protocol stack determined based on the type of core network to which the wireless device ( 14 ) selects to connect.

1 .- 40 . (canceled) 
     
     
         41 . A method performed by a wireless device, the method comprising:
 transmitting, to a radio network node, a radio resource control, RRC, connection request that requests the establishment, re-establishment, or resumption of an RRC connection and that indicates a type of core network to which the wireless device selects to connect, wherein the transmitting of the RRC connection request is without integrity protection and/or confidentiality protection, and   receiving a response to the RRC connection request that is integrity protected and/or confidentiality protected according to a security algorithm that depends on a type of core network indicated by the RRC connection request .   
     
     
         42 . The method of  claim 41 , wherein the RRC connection request indicates the type of core network to which the wireless device selects to connect based on a type of the RRC connection request, wherein different possible types of RRC connection requests indicate different possible types of core networks to which the wireless device selects to connect. 
     
     
         43 . The method of  claim 41 , further comprising selecting a type of core network to which to connect and generating the RRC connection request to indicate the selected type of core network. 
     
     
         44 . The method of  claim 41 , comprising transmitting the RRC connection request on a first type of signaling bearer that uses a first protocol stack, and further comprising receiving a response to the RRC connection request on a second type of signaling bearer that uses different possible protocol stacks depending on a type of core network indicated by the RRC connection request. 
     
     
         45 . The method of  claim 44 , wherein the different possible protocol stacks have different versions of a packet data convergence protocol, PDCP. 
     
     
         46 . The method of  claim 41 , further comprising:
 receiving a response to the RRC connection request based on the type of core network to which the wireless device selects to connect.   
     
     
         47 . The method of  claim 46 , wherein said receiving comprises:
 determining, from different possible protocol stacks supported by the wireless device for receiving a response to the RRC connection request and based on the type of core network to which the wireless device selects to connect, a protocol stack to use for receiving the response to the RRC connection request; and   receiving the response to the RRC connection request using the determined protocol stack.   
     
     
         48 . A method performed by a radio network node, the method comprising:
 receiving, from a wireless device, a radio resource control, RRC, connection request that requests the establishment, re-establishment, or resumption of an RRC connection and that indicates a type of core network to which the wireless device selects to connect, wherein the received RRC connection request is without integrity protection and/or confidentiality protection,   selecting, based on a type of core network indicated by the RRC connection request, a security algorithm to use to apply integrity protection and/or confidentiality protection to a response to the RRC connection request,   applying integrity protection and/or confidentiality protection to the response using the selected security algorithm, and   transmitting the response as integrity protected and/or confidentiality protected.   
     
     
         49 . The method of  claim 48 , wherein the RRC connection request indicates the type of core network to which the wireless device selects to connect based on a type of the RRC connection request, wherein different possible types of RRC connection requests indicate different possible types of core networks to which the wireless device selects to connect. 
     
     
         50 . The method of  claim 48 , comprising receiving the RRC connection request on a first type of signaling bearer that uses a first protocol stack, and further comprising:
 selecting, based on a type of core network indicated by the RRC connection request and from different possible protocol stacks supported by the radio network node, a protocol stack to use for a second type of signaling bearer on which to transmit a response to the RRC connection request; and   transmitting the response to the RRC connection request on the second type of signaling bearer using the selected protocol stack.   
     
     
         51 . The method of  claim 48 , further comprising:
 transmitting a response to the RRC connection request based on the type of core network to which the wireless device selects to connect.   
     
     
         52 . The method of  claim 51 , wherein said transmitting comprises:
 determining, from different possible protocol stacks supported by the radio network node for transmitting the response to the RRC connection request and based on the type of core network to which the wireless device selects to connect, a protocol stack to use for transmitting the response to the RRC connection request; and   transmitting the response to the RRC connection request using the determined protocol stack.   
     
     
         53 . A method performed by a radio network node, the method comprising:
 receiving, from a wireless device, a radio resource control, RRC, connection request that requests the re-establishment or resumption of an RRC connection;   responsive to the RRC connection request, attempting to retrieve a context for the wireless device for re-establishing or resuming the RRC connection; and   determining, based on said attempting to retrieve the context for the wireless device, a type of core network to which the wireless device selects to connect.   
     
     
         54 . The method of  claim 53 , further comprising, before receiving the RRC connection request, releasing or suspending the RRC connection and storing core network type information in the context for the wireless device or in association with the context for the wireless device, wherein the core network type information indicates the type of core network to which the wireless device selected to connect for the RRC connection, wherein said determining comprises determining said type based on the core network type information stored in or in association with the retrieved context. 
     
     
         55 . The method of  claim 53 , further comprising, before receiving the RRC connection request, releasing or suspending the RRC connection and storing the context for the wireless device in one of multiple different possible storage locations respectively associated with different possible types of core networks selectable by the wireless device, wherein said attempting comprises attempting to retrieve the context from one or more of the multiple different possible storage locations and wherein said determining comprises determining said type based on from which possible storage location the context is successfully retrieved. 
     
     
         56 . The method of  claim 53 , wherein said attempting comprises attempting to retrieve the context for the wireless device over one or more of multiple different types of interfaces to another radio network node respectively associated with different types of core networks, and wherein said determining comprises determining said type based on over which type of interface the context is successfully retrieved. 
     
     
         57 . The method of  claim 55 , further comprising retrieving multiple candidate contexts that are candidates for being the context for the wireless device, and determining which of the candidate contexts comprises the context for the wireless device based on which of the candidate contexts includes a security token that is verified by the radio network node. 
     
     
         58 . The method of  claim 53 , further comprising transmitting a response to the RRC connection request based on the type of core network determined. 
     
     
         59 . The method of  claim 53 , comprising receiving the RRC connection request without integrity protection and/or confidentiality protection, and further comprising:
 selecting, based on the type of core network determined, a security algorithm to use to apply integrity protection and/or confidentiality protection to a response to the RRC connection request;   applying integrity protection and/or confidentiality protection to the response using the selected security algorithm; and   transmitting the response as integrity protected and/or confidentiality protected.   
     
     
         60 . The method of  claim 53 , comprising receiving the RRC connection request on a first type of signaling bearer that uses a first protocol stack, and further comprising:
 selecting, based on the type of core network determined and from different possible protocol stacks supported by the radio network node, a protocol stack to use for a second type of signaling bearer on which to transmit a response to the RRC connection request; and   transmitting the response to the RRC connection request on the second type of signaling bearer using the selected protocol stack.   
     
     
         61 . A wireless device comprising:
 communication circuitry; and   processing circuitry configured to
 transmit, to a radio network node, a radio resource control, RRC, connection request that requests the establishment, re-establishment, or resumption of an RRC connection and that indicates a type of core network to which the wireless device selects to connect, wherein the transmitted RRC connection request is without integrity protection and/or confidentiality protection, and 
 receive a response to the RRC connection request that is integrity protected and/or confidentiality protected according to a security algorithm that depends on a type of core network indicated by the RRC connection request. 
   
     
     
         62 . The wireless device of  claim 61 , wherein the RRC connection request indicates the type of core network to which the wireless device selects to connect based on a type of the RRC connection request, wherein different possible types of RRC connection requests indicate different possible types of core networks to which the wireless device selects to connect. 
     
     
         63 . A radio network node comprising:
 communication circuitry; and   processing circuitry configured to
 receive, from a wireless device, a radio resource control, RRC, connection request that requests the establishment, re-establishment, or resumption of an RRC connection and that indicates a type of core network to which the wireless device selects to connect, wherein the received RRC connection request is without integrity protection and/or confidentiality protection, 
 select, based on a type of core network indicated by the RRC connection request, a security algorithm to use to apply integrity protection and/or confidentiality protection to a response to the RRC connection request, 
 apply integrity protection and/or confidentiality protection to the response using the selected security algorithm, and 
 transmit the response as integrity protected and/or confidentiality protected. 
   
     
     
         64 . The radio network node of  claim 63 , wherein the RRC connection request indicates the type of core network to which the wireless device selects to connect based on a type of the RRC connection request, wherein different possible types of RRC connection requests indicate different possible types of core networks to which the wireless device selects to connect. 
     
     
         65 . A radio network node comprising:
 communication circuitry; and   processing circuitry configured to:
 receive, from a wireless device, a radio resource control, RRC, connection request that requests the re-establishment or resumption of an RRC connection; 
 responsive to the RRC connection request, attempt to retrieve a context for the wireless device for re-establishing or resuming the RRC connection; and 
 determine, based on said attempting to retrieve the context for the wireless device, a type of core network to which the wireless device selects to connect. 
   
     
     
         66 . The radio network node of  claim 65 , the processing circuitry further configured to, before receiving the RRC connection request, release or suspend the RRC connection and store core network type information in the context for the wireless device or in association with the context for the wireless device, wherein the core network type information indicates the type of core network to which the wireless device selected to connect for the RRC connection, wherein said type of core network is determined based on the core network type information stored in or in association with the retrieved context.