Dual connectivity flow control
User equipment (UE) can be connected to both a first base station and a second base station. A flow controller at the first base station can determine packet latency goals associated with packets. The flow controller can also determine connection latencies associated with a first connection from the first base station to the UE and a second connection from the second base station to the UE, where one leg of a split bearer passes from the first base station to the UE over the first connection and another leg of the split bearer passes from the first base station to the second base station and then to the UE over the second connection. The flow controller can route packets with lower packet latency goals via the leg of the lower-latency connection, and route other packets with higher packet latency goals over the leg of the higher-latency connection.
1. A method comprising:
receiving, by a flow controller operating on a first base station at a Packet Data Convergence Protocol (PDCP) layer, a set of data packets for a user equipment (UE) from a core network over a split bearer, wherein the split bearer divides at the first base station into a first leg that passes through the first base station to the UE and a second leg that passes from the first base station to the UE via a second base station; determining, by the flow controller, packet latency goals associated with data packets of the set of data packets;
determining, by the flow controller, a first connection latency associated with a first connection from the first base station to the UE and a second connection latency associated with a second connection from the second base station to the UE;
determining, by the flow controller, that one of the first leg and the second leg has lower latency than the other of the first leg and the second leg based on a comparison of the first connection latency and the second connection latency;
grouping, by the flow controller and based on PDCP aggregation, the set of data packets into a first subset associated with lower packet latency goals and a second subset associated with higher packet latency goals, wherein the lower packet latency goals are packet latency goals that are relatively lower compared with the higher packet latency goals;
routing, by the flow controller, the first subset to the UE via the one of the first leg and the second leg that has the lower latency and the second subset to the UE via the other of the first leg and the second leg; and
routing to the UE, by the flow controller, the first subset and the second subset via different ones of the first leg and the second leg based at least in part on a change to at least one of the first connection latency and second connection latency.
2. The method of claim 1 , wherein the routing is based on PDCP aggregation.
3. The method of claim 1 , wherein the flow controller determines the packet latency goals by inspecting the data packets for information about at least one of a priority level, a service type, a Quality of Service (QoS) value, or a Class of Service (CoS) value.
4. The method of claim 3 , wherein the information is indicated by a Differentiated Services Code Point (DSCP) field in headers of the data packets.
5. The method of claim 3 , wherein the information is indicated by Service Data Adaptation Protocol (SDAP) headers of the data packets.
6. The method of claim 1 , wherein one of the first base station and the second base station is a fifth generation (5G) base station and another one of the first base station and the second base station is a Long-Term Evolution (LTE) base station linked to the 5G base station in a dual connectivity configuration.
7. The method of claim 1 , wherein the flow controller determines at least one of the first connection latency and the second connection latency at least in part based on measuring a round-trip time associated with a data transmission between the first base station and the UE over the first connection or between the second base station and the UE over the second connection.
8. The method of claim 1 , wherein the flow controller determines at least one of the first connection latency and the second connection latency at least in part based on at least one of radio conditions, available bandwidth, network congestion levels, numbers of connections to the first base station or the second base station, or a buffer fullness level at the first base station or the second base station.
9. A base station, comprising: one or more processors;
transmission interfaces associated with a first connection to a user equipment (UE), a second connection to a second base station, and a third connection to a core network of a telecommunication network;
memory storing computer-executable instructions for a flow controller that, when executed by the one or more processors, cause the flow controller to operate at a Packet Data Convergence Protocol (PDCP) layer to:
receive a set of data packets for the UE from the core network via a split bearer over the third connection, wherein the split bearer divides into a first leg that passes over the first connection to the UE and a second leg that passes over the second connection to the second base station and from the second base station to the UE;
determine packet latency goals associated with data packets of the set of data packets;
determine a first connection latency associated with the first connection and a second connection latency associated with the second connection;
determine that one of the first leg and the second leg has a lower latency than the other of the first leg and the second leg based on a comparison of the first connection latency and the second connection latency;
group, based on PDCP aggregation, the set of data packets into a first subset associated with lower packet latency goals and a second subset associated with higher packet latency goals, wherein the lower packet latency goals are packet latency goals that are relatively lower compared with the higher packet latency goals;
route the first subset to the UE via the one of the first leg and the second leg that has the lower latency and the second subset to the UE via the other of the first leg and the second leg; and
route, to the UE, the first subset and the second subset via different ones of the first leg and the second leg based at least in part on a change to at least one of the first connection latency and second connection latency.
10. The base station of claim 9 , wherein the flow controller determines the packet latency goals by inspecting the data packets for information about at least one of a priority level, a service type, a Quality of Service (QoS) value, or a Class of Service (CoS) value.
11. The base station of claim 10 , wherein one of the base station and the second base station is a fifth generation (5G) base station and another one of the base station and the second base station is a Long-Term Evolution (LTE) base station linked to the 5 G base station in a dual connectivity configuration.
12. The base station of claim 9 , wherein the flow controller determines at least one of the first connection latency and the second connection latency at least in part based on measuring a round-trip time associated with a data transmission between the base station and the UE over the first connection or between the second base station and the UE over the second connection.
13. The base station of claim 9 , wherein the flow controller determines at least one of the first connection latency and the second connection latency at least in part based on at least one of radio conditions, available bandwidth, network congestion levels, numbers of connections to the base station or the second base station, or a buffer fullness level at the base station or the second base station.
14. One or more non-transitory computer-readable media storing computer-executable instructions that, when executed by one or more processors of a base station of a telecommunication network, cause the base station to perform operations of a flow controller at a Packet Data Convergence Protocol (PDCP) layer, the operations comprising:
receive a set of data packets for a user equipment (UE) from a core network via a split bearer, wherein the split bearer divides into a first leg that passes over a first connection from the base station to the UE and a second leg that passes over a second connection from the base station to a second base station and from the second base station to the UE;
determine packet latency goals associated with data packets of the set of data packets;
determine a first connection latency associated with the first connection and a second connection latency associated with the second connection;
determine that one of the first leg and the second leg has a lower latency than the other of the first leg and the second leg based on a comparison of the first connection latency and the second connection latency;
group, based on PDCP aggregation the set of data packets into a first subset associated with lower packet latency goals and a second subset associated with higher packet latency goals, wherein the lower packet latency goals are packet latency goals that are relatively lower compared with the higher packet latency goals;
route the first subset to the UE via the one of the first leg and the second leg that has the lower latency and the second subset to the UE via the other of the first leg and the second leg; and
route, to the UE, the first subset and the second subset via different ones of the first leg and the second leg based at least in part on a change to at least one of the first connection latency and second connection latency.
15. The one or more non-transitory computer-readable media of claim 14 , wherein the packet latency goals are determined by inspecting the data packets for information about at least one of a priority level, a service type, a Quality of Service (QoS) value, or a Class of Service (CoS) value.
16. The one or more non-transitory computer-readable media of claim 14 , wherein one of the base station and the second base station is a fifth generation (5G) base station and another one of the base station and the second base station is a Long- Term Evolution (LTE) base station linked to the 5G base station in a dual connectivity configuration.
17. The one or more non-transitory computer-readable media of claim 14 , wherein at least one of the first connection latency and the second connection latency is determined at least in part based on one of measuring a round-trip time associated with a data transmission between the base station and the UE over the first connection or between the second base station and the UE over the second connection, radio conditions, available bandwidth, network congestion levels, numbers of connections to the base station or the second base station, or a buffer fullness level at the base station or the second base station.