Patent Description:
<CIT> and <CIT> disclose a method and system in which a first base station in a first communication system obtains an evolved packet system (EPS) bearing information mapped by a QoS flow (quality of service flow) in a packet data unit (PDU) session through a switching process in the system; the first base station sends a switching request message to an access and mobile function entity (AMF), wherein the switching request message includes the EPS bearing information, the first base station receives a switching command message carrying data forwarding channel information sent by the AMF, and the first base station forwards the data according to the received data forwarding channel information. According to the method, the problem of data forwarding when the UE moves between an LTE and a <NUM> system is address, data loss is avoided and service continuity is maintained.

<CIT> discloses a communication scheme and system for converging an IoT technology and a <NUM> communication system to support a high data transmission rate beyond that of a <NUM> system. The application relates to a method of processing an anchor UPF for local offloading when a UE moves in a <NUM> cellular wireless communication system. The disclosure may be applied to intelligent services (for example, services related to a smart home, smart building, smart city, smart car, connected car, health care, digital education, retail business, security, and safety) based on <NUM> communication technology and IoT-related technology.

A wireless cellular network, such as a <NUM> New Radio (NR) cellular network, can be constructed using various architectures. A first architecture may only use one radio access technology (RAT) or a single wireless cellular communication protocol, such as <NUM> NR for the radio access network (RAN) and a <NUM> core as the cellular network's core componentry. Such a dedicated <NUM> NR wireless cellular network can be referred to as a "standalone <NUM> network" and can have certain advantages, such as having a simpler architecture and less expensive to deploy than other forms of cellular networks that include compatibility for other cellular communication protocols. However, a drawback to a standalone <NUM> network may be the lack of compatibility for other cellular protocols. For instance, user equipment (UE) roaming on a non-<NUM> cellular network (e.g., a <NUM> LTE network) or non-standalone <NUM> cellular network (e.g., a network that uses <NUM> for communication with UE but where the core network uses <NUM> Evolved Packet Core (EPC)) may not be possible if the UE's home cellular network's architecture is a standalone <NUM> network that has a <NUM> core and, therefore, does not support additional wireless communication protocols to enable communication with an EPC.

A second possible architecture for a wireless cellular network can involve the cellular network being accessible via multiple RATs or multiple wireless cellular communication protocols. For instance, a cellular network could be compatible with <NUM> LTE and <NUM> NR. While such a network may have both <NUM> and <NUM> network components, the network core may use <NUM> components, which can be referred to as a <NUM> core or EPC. Such an arrangement may have the advantage of being able to accommodate multiple RATs, may help transition from <NUM> to <NUM>, and faster deployment of <NUM>, but may have the drawback of using a less efficient (and possibly more expensive) core network architecture. The core network may be built around an older RAT, such as <NUM>'s EPC architecture with compatibility incorporated for <NUM>.

An anchor point refers to the cellular network core component that serves as a gateway between an external data network, such as the Internet, and the user equipment. For some types of cellular networks, such as the previously-detailed second architecture that can use <NUM> EPC, the anchor point is fixed. That is, regardless of where the UE physically moves while connected with the cellular network, even if hundreds or thousands of miles away, the network's core component that functions as the anchor point between the UE and the data network remains the same. Such an arrangement can result in increased latency, lower bandwidth, or both due to the increased path length between the UE and the data network. However, for some other types of cellular networks, such as the previously-discussed first architecture that uses a <NUM> NR core, the anchor point can be adjusted to decrease latency. Depending on the mode of the cellular network, the anchor point can be reassigned as the UE moves. Therefore, an anchor point that is most efficient (e.g., lowest latency, greatest bandwidth, shortest physical distance) may be used based on where the UE is located.

Embodiments detailed herein capture at least some of the advantages of the first architecture and the second architecture. For instance, embodiments detailed herein focus on a compound cellular network that uses <NUM> core components (and allow for the anchor point to be varied). However, near physical edges of the network footprint, where a UE is more likely to travel into a region where roaming occurs on a separate cellular network (e.g., another carrier's <NUM> LTE network), converged core components may be used that are compatible with multiple RATs (e.g., <NUM> and <NUM>).

Further detail is provided in reference to the figures. <FIG> illustrates an embodiment of a block diagram of a communication environment 100A that includes a compound cellular network. Communication environment 100A includes compound cellular network <NUM> and cellular network <NUM>. Compound cellular network <NUM> may be the primary (e.g., home) cellular network for various pieces of UE. However, occasionally, the UE may use cellular network <NUM> for cellular service, such as in geographical areas where a connection with a base station (BS) of compound cellular network <NUM> cannot be obtained. Physically, it is possible that compound cellular network <NUM> may cover a wholly different geographical region than cellular network <NUM>. However, in many embodiments, there is significant overlap in the geographical regions serviced by compound cellular network <NUM> and cellular network <NUM>.

Compound cellular network <NUM> may include multiple generations of cellular network core components. Compound cellular network <NUM> may include multiple standalone network components <NUM> (e.g., <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>). Each of these standalone network components <NUM> may employ a single RAT, such as 5GNR. When UE physically moves within regions covered by compound cellular network <NUM>, the UE may switch among using various standalone network components <NUM> as an anchor point to access data network <NUM>, which may be the Internet. An anchor point defines the componentry of the cellular network that serves as a gateway between the cellular network and an external data network, such as the Internet. For instance, when a UE is in the vicinity of standalone network components <NUM>-<NUM>, core components of standalone network components <NUM>-<NUM> may be used to access data network <NUM>. At another time, the UE may be located in the vicinity of standalone network components <NUM>-<NUM>, core components of standalone network components <NUM>-<NUM> may then be used to access data network <NUM>.

Converged core network components <NUM> of compound cellular network <NUM> can function similarly to standalone network components <NUM> while a UE is in communication with compound cellular network <NUM>. That is, if a UE moves to a geographic region near converged core network components <NUM>, converged core network components <NUM> may be used as an anchor point to access data network <NUM>. If the UE then moves away and is closer to, for example, standalone network components <NUM>-<NUM>, standalone network components <NUM>-<NUM> may begin being used as the anchor point to access data network <NUM>.

Converged core network components <NUM> has additional capabilities beyond standalone network components <NUM>. While standalone network components <NUM> can communicate using only a single cellular RAT, such as <NUM>, converged core network components <NUM> include core components that function using multiple cellular standards, such as <NUM> NR and <NUM> LTE EPC. When UE is communicating with cellular network <NUM>, which can be a <NUM> LTE cellular network, non-standalone <NUM> cellular network, or a cellular network based on some other RAT, regardless of which of second cellular network core components <NUM> that the UE is communicating with, converged core network components <NUM> remains used as the anchor point to access data network <NUM>. Therefore, regardless of where the UE roams within cellular network <NUM>, the anchor point is fixed to be converged core network components <NUM>.

In order to decrease latency, converged core network components <NUM> may be located near where UE is expected to use cellular network <NUM>. For instance, converged core network components <NUM> can be located near where a coverage area of compound cellular network <NUM> ends, but where coverage of cellular network <NUM> begins or continues.

<FIG> illustrates another embodiment of a block diagram of a communication environment 100B that includes a compound cellular network. In communication environment 100B, multiple converged core network components (<NUM>, <NUM>) are illustrated as part of compound cellular network <NUM>. As detailed in relation to <FIG>, compound cellular network <NUM> may include multiple standalone network components <NUM> (e.g., <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>). Each of these standalone network components <NUM> may employ a single RAT, such as <NUM> NR. When UE physically moves within regions covered by compound cellular network <NUM>, the UE may switch among using various standalone network components <NUM> as an anchor point to access data network <NUM>, which may be the Internet.

Converged core network components <NUM> and <NUM> of compound cellular network <NUM> can function similarly to standalone network components <NUM> while a UE is in communication with compound cellular network <NUM>. That is, if a UE moves to a geographic region near converged core network components <NUM> or converged core network components <NUM>, converged core network components <NUM> or <NUM> may be used as an anchor point to access data network <NUM>.

Converged core network components <NUM> and <NUM> include core components that function using multiple cellular standards, such as <NUM> NR and <NUM> LTE EPC. When a UE transitions to communicating using cellular network <NUM> instead of compound cellular network <NUM>, the components of compound cellular network <NUM> used as the anchor point to access data network <NUM> becomes fixed. For instance, if the UE was previously communicating with converged core network components <NUM> and then roams onto cellular network <NUM>, converged core network components <NUM> may be used as the fixed anchor point for as long as the UE is roaming on cellular network <NUM> (regardless of where the UE roams within cellular network <NUM>). If the UE was previously communicating with converged core network components <NUM> and then roams onto cellular network <NUM>, converged core network components <NUM> may be used as the fixed anchor point for as long as the UE is roaming on cellular network <NUM> (regardless of where the UE roams within cellular network <NUM>).

The UE may be assigned a particular converged core network components of compound cellular network <NUM> when the UE begins roaming on cellular network <NUM> to be used as the anchor point for the duration of the time that the UE is roaming on cellular network <NUM>. For instance, if a UE was previously connected with standalone network components <NUM>-<NUM> then is next connected with second cellular network core components <NUM>-<NUM> of cellular network <NUM>, either converged core network components <NUM> or converged core network components <NUM> may be selected by compound cellular network <NUM> to serve as the anchor point for the UE for the duration of the time that the UE is roaming within cellular network, regardless of where the UE roams within cellular network <NUM>. The selection may be based on latency, geographic location, or one or more other factors.

As an example of how an anchor point is locked, if a UE connects with cellular network <NUM> using second cellular network core components <NUM>-<NUM>, converged core network components <NUM> of compound cellular network <NUM> may be locked as the anchor point for accessing data network <NUM>. If the UE moves and later communicates with second cellular network core components <NUM>-<NUM>, even if converged core network components <NUM> would have lower latency or is geographically closer, converged core network components <NUM> remains used as the anchor point for the duration of the time that the UE is connected with cellular network <NUM>.

If the UE disconnects from cellular network <NUM> and communicates directly with either converged core network components <NUM>, converged core network components <NUM>, or one or standalone network components <NUM>, the anchor point may resume being shifted among these components. If the UE then reconnects with cellular network <NUM>, an anchor point may be selected (and thus may be a different converged core network components of compound cellular network <NUM>) and again may be locked.

In the examples of <FIG> and <FIG>, the number of standalone network components <NUM>, converged core network components <NUM> and <NUM>, and second cellular network core components <NUM> is merely exemplary. In real-word implementations, the number of cellular networks from which a UE can roam onto from compound cellular network <NUM> may be greater than one and many more components and components may be present.

<FIG> illustrates an embodiment of a communication environment <NUM>. Communication environment <NUM> represents a more detailed embodiment of <FIG>. Communication environment <NUM> can be used in the context of bridging functionality between a <NUM> NR and a <NUM> LTE network on to which UE may roam. The communication environment <NUM> includes: compound cellular network <NUM> and cellular network <NUM>. Compound cellular network <NUM> includes multiple portions, including: standalone network portion <NUM>; and converged core network portion <NUM>. Standalone network portion <NUM> represents a portion of compound cellular network <NUM> that includes a RAN and core components that function according to a single RAT, such as <NUM>. Standalone network portion <NUM> may only communicate using one RAT, such as <NUM> NR. Within standalone network portion <NUM> may be multiple anchor points. For a cellular network using <NUM> core components, the anchor point can be referred to as a UPF (user plane function). UPF <NUM> serve as the gateway between UE and data network <NUM>, which may be the Internet. Multiple UPFs <NUM> (<NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>) are present. Each UPF may serve one or more base stations of base stations <NUM>. Base stations <NUM> can be gNodeBs (gNBs) in a <NUM> NR network. The UPF of UPFs <NUM> that serves a given base station of base stations <NUM> may be fixed.

As depicted, each UPF of UPF <NUM> are illustrated as in communication with particular base stations of base stations <NUM>. Depending on the Session and Service Continuity (SSC) mode used for standalone network portion <NUM>, which particular UPF a base station is communicating with on behalf of a UE may vary. For instance, in a first mode (e.g., SSC3), despite a UE moving among base stations, the UE may continue using a UPF as its anchor point until a new connection with a more efficient (e.g., lower latency, higher bandwidth, shorter geographic distance) UPF is made, which can be referred to colloquially as "make-before-break. " In another mode (e.g., SSC2), a connection with the previously-used UPF may be ended before a new connection with a more efficient UPF is made, which can be referred to colloquially as "break-before-make. " Therefore, while connections indicate the UPF which may be most efficient for a given base station, base stations may route data for UEs with other UPFs if needed.

If the compound cellular network is set to a permissible mode (e.g., SSC2 or SSC3 for 5GNR), as a UE moves within standalone network portion <NUM> and connects with different base stations of base stations <NUM>, the UPF used to connect the UE with data network <NUM> can change. For instance, if a UE was connected with base station <NUM>-<NUM>, UPF <NUM>-<NUM> may be used as the anchor point for the UE to communicate with data network <NUM>. If the UE moves and begins communicating with base station <NUM>-<NUM>, UPF <NUM>-<NUM> can be used as the anchor point for the UE to communicate with data network <NUM>.

Converged core network portion <NUM> represents a portion of compound cellular network <NUM> that includes core components that are compatible with multiple RATs (multiple cellular communication protocols, such as <NUM> NR and <NUM> LTE. Rather than having the same type of anchor points as standalone network portion <NUM>, converged core network portion <NUM> can have one or more anchor points that are compatible with multiple RATs. While a UE is operating as part of converged core network portion <NUM>, such as by having a wireless connection with base station <NUM>, functionality may be similar to as if the UE was within standalone network portion <NUM>. That is, the anchor point may be adjusted to be UPF/PGW <NUM>. While the UE is directly connected with a base station of converged core network portion <NUM>, UPF/PGW <NUM> may function similarly to UPFs <NUM>. For instance, if the UE moves back into standalone network portion <NUM>, a transition may occur such that a different UPF is used as the UE's anchor point.

UPF/PGW <NUM> (User Plane Function/Packet Gateway) can represent a single component or multiple components functioning in concert. While a UPF may be used as a gateway between data network <NUM> and UE for <NUM> communication; a PGW may perform a similar function for <NUM> communication.

A UE may exit the region of compound cellular network <NUM> that has converged core regional data centers and may roam on cellular network <NUM>. Cellular network <NUM> can be operated by a different network provider than compound cellular network <NUM>. For instance, the provider of compound cellular network <NUM> may have an operating agreement with the provider of cellular network <NUM>. Cellular network <NUM> operates using a different RAT than standalone network portion <NUM>. For instance, cellular network <NUM> be a <NUM> LTE network or a <NUM> non-standalone network (that uses <NUM> EPC as its core). <NUM> LTE and <NUM> non-standalone (utilizing <NUM> EPC) differs from a standalone <NUM> NR network in that anchor points in a <NUM> EPC core network are fixed. While a UE is communicating with a base station of base stations <NUM> of cellular network <NUM>, UPF/PGW <NUM> may remain the anchor point used for the UE regardless of where the UE roams within cellular network <NUM>.

Within cellular network <NUM>, each of base stations <NUM> may communicate with a serving gateway (SGW) <NUM>. A SGW may forward data communications to the PGW servicing the UE, which would be UPF/PGW <NUM> of converged core network portion <NUM>. If the UE moves within cellular network <NUM>, the SGW of SGWs <NUM> used for forwarding data to UPF/PGW <NUM> may vary, but the anchor point for communicating with data network <NUM> remains UPF/PGW <NUM>. UPF/PGW <NUM> may remain the anchor point at least until the UE disconnects from cellular network <NUM> and reconnects with compound cellular network <NUM>. If the UE reconnects with a base station (e.g., base station <NUM>) that is part of converged core network portion <NUM>, UPF/PGW <NUM> may remain, at least initially, the anchor point for communication with data network <NUM>. However, if the UE reconnects with another base station, such as base station <NUM>-<NUM>, a UPF of UPFs <NUM> may be used as the anchor point instead.

Converged core network portion <NUM> may overlap with cellular network <NUM>. That is, converged core network portion <NUM> may represent a region where UE can communicate with both compound cellular network <NUM> and cellular network <NUM>. However, since compound cellular network <NUM> is the UE's home network, the UE would not connect with cellular network <NUM> unless compound cellular network <NUM> is unavailable. Regardless of whether converged core network portion <NUM> overlaps the coverage area of cellular network <NUM> or not, converged core network portion <NUM> may be located near a geographic edge of compound cellular network <NUM>. Since the PGW functionality of converged core network portion <NUM> is only needed when a UE is communicating with a roaming cellular network that requires <NUM> compatibility or non-standalone <NUM> compatibility, there can be no need for implementing PGW functionality in standalone network portion <NUM>. One possible goal when choosing a location for converged core network portion <NUM> may be to locate it such that UPF/PGW <NUM> will have relatively low latency for a large region in which UE may be expected to roam on cellular network <NUM>.

<FIG> illustrates an embodiment <NUM> of a UE moving within and roaming off of the compound cellular network. Embodiment <NUM> represents a UE moving within compound cellular network and roaming on cellular network <NUM>. A UE may be any type of communication equipment that is capable of exchanging data with a wireless cellular network. Examples of UE can involve smartphones, cellular phones, tablet computer, wireless modems, laptop computers, and wireless access points (APs).

In embodiment <NUM>, a single UE is depicted moving from UE location <NUM> to UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>-<NUM> of standalone network portion <NUM>. Assuming standalone network portion <NUM> is <NUM> and uses a <NUM> core network, the UE may connect to data network <NUM> using UPF <NUM>-<NUM> as the anchor point. The UE may move the UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>-<NUM>. The UE may be transitioned from using UPF <NUM>-<NUM> to using UPF <NUM>-<NUM> as the anchor point to connect with data network <NUM>. The UE may move to UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>. While base station <NUM> is part of converged core network portion <NUM>, since the UE is still directly connected with compound cellular network <NUM>, the anchor point can continue to be moved. UPF/PGW <NUM> may be used as the anchor point for the UE communicating with data network <NUM>.

At UE location <NUM>, the UE has begun roaming on cellular network <NUM>. Assuming cellular network <NUM> uses <NUM> as its RAT, UPF/PGW <NUM> is now locked as the anchor point for the UE to communicate with data network <NUM>. Therefore, regardless of where the UE travels within cellular network <NUM>, UPF/PGW <NUM> with remain the UE's anchor point. At UE location <NUM>, the UE may communicate with base station <NUM>-<NUM>, which may be an eNodeB (eNB). The UE may communicate with UPF/PGW <NUM> via SGW <NUM>-<NUM>. The UE may move to UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>-<NUM>. To communicate with data network <NUM>, data may be routed through SGW <NUM>-<NUM> and UPF/PGW <NUM>. At UE location <NUM>, the UE may be communicating with base station <NUM>-<NUM>. Again here, to communicate with data network <NUM>, data may be routed through SGW <NUM>-<NUM> and UPF/PGW <NUM>. However, when the UE moves to UE location <NUM>, since the UE is now back on compound cellular network <NUM>, the anchor point of the UE may be transitioned to UPF <NUM>-<NUM>.

<FIG> illustrates an embodiment <NUM> of a UE moving within and roaming off of compound cellular network <NUM>. Embodiment <NUM> represents a UE moving within compound cellular network and roaming on cellular network <NUM>. In this embodiment, UPF/PGW <NUM> is not located in a geographic region that physical overlaps a coverage area of cellular network <NUM>.

In embodiment <NUM>, a single UE is depicted moving from UE location <NUM> to UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>-<NUM>, which is part of a standalone network portion. UPF <NUM>-<NUM> is part of a standalone <NUM> network portion and uses a <NUM> core network, therefore the UE may connect to data network <NUM> using UPF <NUM>-<NUM> as the anchor point. The UE may move the UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>-<NUM>. The UE may be transitioned from using UPF <NUM>-<NUM> to using UPF <NUM>-<NUM> as the anchor point to connect with data network <NUM>. The UE may then move to UE location <NUM>. At UE location <NUM>, the UE may communicate with base station <NUM>, which is connected with SGW <NUM>-<NUM>. A PGW that is part of compound cellular network <NUM> may be used as a fixed anchor point for the remainder of time that the UE is roaming on cellular network <NUM>. SGW <NUM>-<NUM> may communicate with UPF/PGW <NUM> of compound cellular network <NUM>. In some embodiments, a private network connection is used between SGW <NUM>-<NUM> and UPF/PGW <NUM>; in other embodiments, data network <NUM> may be used for communication between SGW <NUM>-<NUM> and UPF/PGW <NUM>.

At UE location <NUM>, the UE may communicate with BS <NUM>-<NUM>, which communicates with SGW <NUM>-<NUM>. SGW <NUM>-<NUM> may communicate with UPF/PGW <NUM>, which remains the anchor point, either via a private network connection or via data network <NUM>. At UE location <NUM>, the UE may communication with BS <NUM>-<NUM>, which may communicate with SGW <NUM>-<NUM>. SGW <NUM>-<NUM> may communicate with UPF/PGW <NUM> either via a private network connection or via data network <NUM>. Similarly, at UE location <NUM>, may communicate with BS <NUM>-<NUM>, which continues to communicate using SGW <NUM>-<NUM>.

At UE location <NUM>, the UE has resumed communicating with compound cellular network <NUM>. Since the UE has resumed communicating with compound cellular network <NUM>, the anchor point is no longer locked. At UE location <NUM>, the UE is communicating with BS <NUM>-<NUM>. For BS <NUM>-<NUM>, UPF <NUM>-<NUM> is used as the anchor point, either because UPF <NUM>-<NUM> is assigned to BS <NUM>-<NUM> or UPF <NUM>-<NUM> results in one or more beneficial characteristics, such as relatively low latency compared to other UPFs. As the UE moves throughout compound cellular network <NUM>, the UPF used as the anchor point can continue to change. If the UE moves onto cellular network <NUM>, the anchor point may again be locked to a PGW of compound cellular network <NUM>, which may be the same PGW previously used or a different PGW.

Various methods may be performed using the systems detailed in relation to <FIG>. <FIG> illustrates an embodiment of a method <NUM> for managing anchor point movement in a compound cellular network. At block <NUM>, a UE may be connected with a data network via a first anchor point while the UE is communicating with a compound cellular network. This first anchor point may be a UPF that is not capable of functioning as a PGW for <NUM> RAT or non-standalone <NUM>. The compound cellular network can include a standalone <NUM> core portion and a converged <NUM>/<NUM> core portion. At block <NUM>, the UE may move to a new location that is geographically covered by the compound cellular network. In other embodiments, method <NUM> may proceed directly to block <NUM>. At block <NUM>, the anchor point assigned to the UE may be transitioned from the first anchor point to a second anchor point. This second anchor point may also be a UPF that is not capable of functioning as a PGW for <NUM> RAT or non-standalone <NUM>. Since the UE is connected with the compound cellular network, assuming the compound cellular network is set to a mode that permits it (e.g., SSC3), the anchor point can be changed, such as to allow for more efficient (e.g., lower latency, higher bandwidth) communication between the UE and the data network. At block <NUM>, the UE may be connected with the data network using the second anchor point while the UE is communicating with the compound cellular network.

At block <NUM>, the UE may move to another new physical location. At the new location, the UE may roam on a different cellular network, which can be operated by a different network provider. This other cellular network may be <NUM> LTE, non-standalone <NUM> (in both embodiments, <NUM> EPC is used for the network's core), or some other cellular network standard. At block <NUM>, the compound cellular network may transition the UE's anchor point from the second anchor point to a converged anchor point that can function as a PGW. At block <NUM>, the PGW may be locked as the anchor point for the UE while the UE is roaming on the different cellular network that uses <NUM> or non-standalone <NUM>. Regardless of where the UE roams on this other cellular network, the PGW of block <NUM> will remain the anchor point between a data network and the UE.

Once the UE returns to its home network, the anchor point is no longer locked and the anchor point can be moved among UPFs and converged UPF/PGWs of the compound cellular network. If the UE again roams onto a <NUM> LTE network or non-standalone <NUM> network, a converged UPF/PGW is again used as a fixed anchor point for the remainder of the time that the UE is roaming on the <NUM> or non-standalone <NUM> cellular network.

Specific details are given in the description to provide a thorough understanding of example configurations (including implementations). However, configurations may be practiced without these specific details. For example, well-known circuits, processes, algorithms, structures, and techniques have been shown without unnecessary detail in order to avoid obscuring the configurations. This description provides example configurations only, and does not limit the scope, applicability, or configurations of the claims. Rather, the preceding description of the configurations will provide those skilled in the art with an enabling description for implementing described techniques. Various changes may be made in the function and arrangement of elements without departing from the scope of the claimed invention.

Also, configurations may be described as a process which is depicted as a flow diagram or block diagram. Although each may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process may have additional steps not included in the figure. Furthermore, examples of the methods may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware, or microcode, the program code or code segments to perform the necessary tasks may be stored in a non-transitory computer-readable medium such as a storage medium. Processors may perform the described tasks.

Claim 1:
A compound cellular network (<NUM>) that accommodates multiple cellular communication protocols, the system comprising:
a standalone network portion (<NUM>) of a first cellular network comprising a plurality of anchor points, wherein:
the standalone network portion (<NUM>) is configured to operate according to only a first cellular communication protocol;
the plurality of anchor points (<NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>) are geographically distributed;
each anchor point of the plurality of anchor points (<NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>) is a cellular network core component configured to serve as a gateway for a user equipment to communicate with an external data network (<NUM>); and
which anchor point of the plurality of anchor points (<NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>) is configured to serve as the gateway for the user equipment is configured to be varied based on latency or load;
a converged core network portion (<NUM>) of the first cellular network, comprising a converged anchor point (<NUM>) distinct from the plurality of anchor points (<NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>), wherein:
the converged core network portion (<NUM>) is configured to operate according to the first cellular communication protocol and a second cellular communication protocol;
when the user equipment connects with a separate, second cellular network (<NUM>) configured to use the second cellular communication protocol, the user equipment is locked to the converged anchor point (<NUM>) of the converged core network portion (<NUM>) of the first cellular network as the gateway (<NUM>) with the external data network (<NUM>), such that the user equipment uses the converged anchor point (<NUM>) to access the external data network (<NUM>) for the duration of time that the user equipment is connected with the second cellular network (<NUM>); and
wherein the converged core network portion (<NUM>) is located near a geographical edge of the compound cellular network (<NUM>) such that beyond the geographical edge, the user equipment roams on the second cellular network (<NUM>) configured to use the second cellular communication protocol.