Filter-based control information query in software-defined networking (SDN) environments

1. A method for a host to perform filter-based control information query in a software-defined networking (SDN) environment that includes the host and a network management entity, wherein the method comprises:

identifying a first query key for querying control information associated with the first query key from the network management entity;

applying a set membership filter to determine whether the first query key is possibly a member of a set of second query keys that are known to the network management entity; and

in response to determination that the first query key is possibly a member of the set of second query keys, generating and sending a query message to the network management entity over a control-plane channel to query for the control information associated with the first query key; otherwise, not generating and sending the query message to the network management entity.

2. The method of claim 1 , wherein the method further comprises:

configuring the set membership filter based on configuration information from the network management entity, wherein the set membership filter includes k hash functions, and an array with m elements that are configured based on the set of second query keys.

3. The method of claim 2 , wherein applying the set membership filter comprises:

applying the k hash functions on the first query key to map the first query key onto k elements in the array; and

determining whether the first query key is possibly a member of the set of second query keys based on the k elements.

4. The method of claim 1 , wherein identifying the first query key comprises:

performing snooping to detect, from a virtualized computing instance supported by the host, an address resolution request message that specifies an Internet Protocol (IP) address associated with a destination with which the virtualized computing instance wishes to communicate; and

identifying the IP address to be the first query key for retrieving control information that includes a Media Access Control (MAC) address associated with the destination.

5. The method of claim 4 , wherein the method comprises:

receiving, from the network management entity responsive to the query message, the control information that includes the MAC address associated with the destination; and

generating and sending an address resolution response message to the virtualized computing instance, wherein the address resolution response message identifies the IP address and the MAC address.

6. The method of claim 4 , wherein the method comprises:

determining that the first query key is not a member of the set of second query keys after applying the set membership filter, or receiving an invalid result message from the network management entity responsive to the query message, wherein the invalid result message indicates a false positive produced by the set membership filter; and

broadcasting the address resolution request message within a logical overlay network in which the virtualized computing instance is located.

7. The method of claim 1 , wherein identifying the first query key comprises:

identifying a MAC address to be the first query key for retrieving control information that includes virtual tunnel endpoint (VTEP) information associated with a destination host, wherein the destination host supports a destination virtualized computing instance associated with the MAC address.

8. A non-transitory computer-readable storage medium that includes a set of instructions which, in response to execution by a processor of a computer system, cause the processor to perform a method of filter-based control information query in a software-defined networking (SDN) environment that includes the computer system and a network management entity, wherein the method comprises:

identifying a first query key for querying control information associated with the first query key from the network management entity;

applying a set membership filter to determine whether the first query key is possibly a member of a set of second query keys that are known to the network management entity; and

in response to determination that the first query key is possibly a member of the set of second query keys, generating and sending a query message to the network management entity over a control-plane channel to query for the control information associated with the first query key; otherwise, not generating and sending the query message to the network management entity.

9. The non-transitory computer-readable storage medium of claim 8 , wherein the method further comprises:

configuring the set membership filter based on configuration information from the network management entity, wherein the set membership filter includes k hash functions, and an array with m elements that are configured based on the set of second query keys.

10. The non-transitory computer-readable storage medium of claim 9 , wherein applying the set membership filter comprises:

applying the k hash functions on the first query key to map the first query key onto k elements in the array; and

determining whether the first query key is possibly a member of the set of second query keys based on the k elements.

11. The non-transitory computer-readable storage medium of claim 8 , wherein identifying the first query key comprises:

performing snooping to detect, from a virtualized computing instance, an address resolution request message that specifies an Internet Protocol (IP) address associated with a destination with which the virtualized computing instance wishes to communicate; and

identifying the IP address to be the first query key for retrieving control information that includes a Media Access Control (MAC) address associated with the destination.

12. The non-transitory computer-readable storage medium of claim 11 , wherein the method comprises:

receiving, from the network management entity responsive to the query message, the control information that includes the MAC address associated with the destination; and

generating and sending an address resolution response message to the virtualized computing instance, wherein the address resolution response message identifies the IP address and the MAC address.

13. The non-transitory computer-readable storage medium of claim 11 , wherein the method comprises:

determining that the first query key is not a member of the set of second query keys after applying the set membership filter, or receiving an invalid result message from the network management entity responsive to the query message, wherein the invalid result message indicates a false positive produced by the set membership filter; and

broadcasting the address resolution request message within a logical overlay network in which the virtualized computing instance is located.

14. The non-transitory computer-readable storage medium of claim 8 , wherein identifying the first query key comprises:

identifying a MAC address to be the first query key for retrieving control information that includes virtual tunnel endpoint (VTEP) information associated with a destination host, wherein the destination host supports a destination virtualized computing instance associated with the MAC address.

15. A host configured to perform filter-based control information query in a software-defined networking (SDN) environment that includes the host and a network management entity, wherein the host comprises:

a processor; and

a non-transitory computer-readable medium having stored thereon instructions that, when executed by the processor, cause the processor to:

identify a first query key for querying control information associated with the first query key from the network management entity;

apply a set membership filter to determine whether the first query key is possibly a member of a set of second query keys that are known to the network management entity; and

in response to determination that the first query key is possibly a member of the set of second query keys, generate and send a query message to the network management entity over a control-plane channel to query for the control information associated with the first query key; otherwise, not generate and send the query message to the network management entity.

16. The host of claim 15 , wherein the instructions further cause the processor to:

configure the set membership filter based on configuration information from the network management entity, wherein the set membership filter includes k hash functions, and an array with m elements that are configured based on the set of second query keys.

17. The host of claim 16 , wherein instructions for applying the set membership filter cause the processor to:

apply the k hash functions on the first query key to map the first query key onto k elements in the array; and

determine whether the first query key is possibly a member of the set of second query keys based on the k elements.

18. The host of claim 15 , wherein instructions for identifying the first query key cause the processor to:

perform snooping to detect, from a virtualized computing instance supported by the host, an address resolution request message that specifies an Internet Protocol (IP) address associated with a destination with which the virtualized computing instance wishes to communicate; and

identify the IP address to be the first query key for retrieving control information that includes a Media Access Control (MAC) address associated with the destination.

19. The host of claim 18 , wherein the instructions further cause the processor to:

receive, from the network management entity responsive to the query message, the control information that includes the MAC address associated with the destination; and

generate and sending an address resolution response message to the virtualized computing instance, wherein the address resolution response message identifies the IP address and the MAC address.

20. The host of claim 18 , wherein the instructions further cause the processor to:

determine that the first query key is not a member of the set of second query keys after applying the set membership filter, or receiving an invalid result message from the network management entity responsive to the query message, wherein the invalid result message indicates a false positive produced by the set membership filter; and

broadcast the address resolution request message within a logical overlay network in which the virtualized computing instance is located.

21. The host of claim 15 , wherein instructions for identifying the first query key cause the processor to:

identify a MAC address to be the first query key for retrieving control information that includes virtual tunnel endpoint (VTEP) information associated with a destination host, wherein the destination host supports a destination virtualized computing instance associated with the MAC address.