Network slicing including modeling, distribution, traffic engineering and maintenance
The techniques describe network slicing in computer networks. For example, a node receives a slice policy definition. The slice policy definition comprising a slice selector to identify packets belonging to one or more network slices, referred to as a “slice aggregate,” and one or more network resource requirements for the slice aggregate to meet one or more Service Level Objectives (SLOs). The node configures, based on the slice policy definition, a path for the slice aggregate that complies with the one or more network resource requirements. In response to receiving a packet, the node determines whether the packet is associated with the slice aggregate and, in response to determining that the packet is associated with the slice aggregate, forwards the packet along the path for the slice aggregate.
1. A network controller comprising:
a memory;
one or more processors operably coupled to the memory, wherein the one or more processors are configured to:
receive a network slice intent to instantiate a plurality of network slices having a logical network topology to connect a plurality of network slice endpoints using one or more nodes of an underlay network in accordance with one or more Service Level Objectives (SLOs);
map the plurality of network slices to a slice aggregate, wherein the slice aggregate comprises one or more packet flows belonging to the plurality of network slices;
generate a slice policy definition for the slice aggregate, wherein the slice policy definition comprises:
a global identifier slice selector used to identify the slice aggregate, wherein the global identifier slice selector comprises at least one of a single forwarding address or a single Multiprotocol Label Switching (MPLS) label associated with the slice aggregate, and
one or more network resource requirements for the slice aggregate to meet the one or more SLOs; and
send the slice policy definition to the one or more nodes of the underlay network to cause the one or more nodes to identify, based on the global identifier slice selector, the slice aggregate and to allocate one or more network resources for the slice aggregate, based on the one or more network resource requirements for the slice aggregate, for forwarding a packet including the global identifier slice selector along a path of the slice aggregate, wherein the global identifier slice selector in the packet is independent of a forwarding address or MPLS label associated with a destination of the packet.
2. The controller of claim 1 , wherein the slice policy definition comprises:
a data plane policy comprising at least the global identifier slice selector;
a control plane policy comprising at least an amount of the one or more network resources to be allocated, a network resource sharing requirement to share the one or more network resources with a plurality of slice aggregates, or a reservation priority to prioritize the one or more network resources for one or more slice aggregates of the plurality of slice aggregates; and
a topology membership policy comprising a topology filter policy that specifies a network topology for the slice aggregate.
3. The controller of claim 2 , wherein the topology filter policy comprises a flexible-algorithm definition or a multi-topology identifier.
4. A node of a plurality of nodes of an underlay network, the node comprising:
a forwarding component comprising processing circuitry; and
a routing component comprising processing circuitry and configured to:
receive, from a controller, a slice policy definition, wherein the slice policy definition comprises:
a global identifier slice selector to identify to a slice aggregate, wherein the slice aggregate comprises one or more packet flows belonging to a plurality of network slices having a logical network topology to connect a plurality of network slice endpoints using one or more nodes of an underlay network in accordance with one or more Service Level Objectives (SLOs), wherein the global identifier slice selector comprises at least one of a single forwarding address or a single Multiprotocol Label Switching (MPLS) label associated with the slice aggregate, and
one or more network resource requirements for the slice aggregate to meet the one or more SLOs;
identify, based on the global identifier slice selector, the slice aggregate;
configure, based on the one or more network resource requirements for the slice aggregate, a path for the slice aggregate; and
wherein, based on the configuration of the path for the slice aggregate, the processing circuitry of the forwarding component is configured to:
receive a packet; and
based on determining that the packet includes the global identifier slice selector, forward the packet along the path for the slice aggregate, wherein the global identifier slice selector in the packet is independent of a forwarding address or MPLS label associated with a destination of the packet.
5. The node of claim 4 ,
wherein the node is an ingress node to the slice aggregate, and
wherein, to forward the packet along the path, the forwarding component is further configured to include the global identifier slice selector in the packet.
6. The node of claim 5 , wherein, to forward the packet along the path, the forwarding component further configured to include a Differentiated Service Class Selector in the packet to differentiate the packet from among a plurality of packets associated with the slice aggregate.
7. The node of claim 4 , wherein the routing component is further configured to:
send a routing protocol message including slice aggregate information to another node of the plurality of nodes.
8. The node of claim 7 , wherein the slice aggregate information comprises one or more of an indication that the node is capable of slice aggregate aware traffic engineering, link identification information for a link of the slice aggregate, attributes of the link, unreserved bandwidth of the link, residual bandwidth of the link, available bandwidth of the link, utilized bandwidth of the link, a prefix-segment identifier of the slice aggregate, an adjacency-segment identifier of the slice aggregate, a local area network (LAN) adjacency-segment identifier, or a segment routing version 6 segment identifier.
9. The node of claim 7 , wherein the routing protocol message includes at least one of an intermediate system to intermediate system (IS-IS) protocol message, or an Open Shortest Path First (OSPF) protocol message, or a Border Gateway Protocol (BGP) message.
10. The node of claim 4 , wherein to receive the slice policy definition, the routing component is further configured to:
receive a routing protocol message including the slice policy definition from another node of the plurality of nodes.
11. The node of claim 10 , wherein the routing protocol message includes at least one of an intermediate system to intermediate system (IS-IS) protocol message, or an Open Shortest Path First (OSPF) protocol message, or a Border Gateway Protocol (BGP) message.
12. A method comprising:
receiving, from a controller and by a node of a plurality of nodes in an underlay network, a slice policy definition, wherein the slice policy definition comprises:
a global identifier slice selector to identify a slice aggregate, wherein the slice aggregate comprises one or more packet flows belonging to a plurality of network slices having a logical network topology to connect a plurality of network slice endpoints using one or more nodes of an underlay network in accordance with one or more Service Level Objectives (SLOs), wherein the global identifier slice selector comprises at least one of a single forwarding address or a single Multiprotocol Label Switching (MPLS) label associated with the slice aggregate, and
one or more network resource requirements for the slice aggregate to meet the one or more SLOs;
identifying, by the node and based on the global identifier slice selector associated with the slice aggregate, the slice aggregate;
configuring, by the node and based on the one or more network resource requirements for the slice aggregate, a path for the slice aggregate;
receiving, by the node, a packet; and
based on determining that the packet includes the global identifier slice selector, forwarding, by the node, the packet along the path for the slice aggregate, wherein the global identifier slice selector in the packet is independent of a forwarding address or MPLS label associated with a destination of the packet.
13. The method of claim 12 ,
wherein the node is an ingress node to the slice aggregate, and
wherein forwarding the packet along the path comprises including the global identifier slice selector in the packet.
14. The method of claim 13 , wherein, forwarding the packet along the path comprises including a Differentiated Service Class Selector in the packet to differentiate the packet from among a plurality of packets associated with the slice aggregate.
15. The method of claim 12 , wherein receiving the slice policy definition comprises:
receiving a routing protocol message including slice aggregate information from another node of the plurality of nodes, wherein the routing protocol message includes at least one of an intermediate system to intermediate system (IS-IS) protocol message, or an Open Shortest Path First (OSPF) protocol message, or a Border Gateway Protocol (BGP) message.
16. The method of claim 15 , wherein the slice aggregate information comprises one or more of an indication that the node is capable of slice aggregate aware traffic engineering, link identification information for a link of the slice aggregate, attributes of the link, unreserved bandwidth of the link, residual bandwidth of the link, available bandwidth of the link, utilized bandwidth of the link, a prefix-segment identifier of the slice aggregate, an adjacency-segment identifier of the slice aggregate, a local area network (LAN) adjacency-segment identifier, or a segment routing version 6 segment identifier.
17. The controller of claim 1 , wherein the one or more processors are further configured to:
send the slice policy definition to a proxy node using a transport mechanism including at least one of NETCONF, RESTCONF, or gRPC, and
wherein the proxy node is configured to send, to other nodes of the one or more nodes, a routing protocol message including the slice policy definition, wherein the routing protocol message includes at least one of an intermediate system to intermediate system (IS-IS) protocol message, or an Open Shortest Path First (OSPF) protocol message, or a Border Gateway Protocol (BGP) message.