Multiple VLAN Architecture system

• US 6,219,699 B1
• Filed: 03/26/1999
• Issued: 04/17/2001
• Est. Priority Date: 01/02/1996
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Young, Christopher, Finn, Norman W., James, Bernard R., McCloghrie, Keith
• Primary Examiner(s): Pan, Daniel H.
• Application Number:
  US09/277,329
• Time in Patent Office: 753 Days
• Field of Search: 370/396, 370/250, 370/230, 370/254, 370/392, 370/420, 370/351, 370/356, 370/452, 380/50, 365/49, 710/10, 709/218, 709/231, 709/272, 709/220, 709/221, 709/226, 714/4
• US Class Current: 709/221
• CPC Class Codes: H04L 12/4645 Details on frame tagging routing of packets H04L45/00; support for virtual LAN H04L49/354
• CPC Class Codes: H04L 12/4666 Operational details on the addition or the stripping of a tag in a frame, e.g. at a provider edge node
• CPC Class Codes: H04L 12/4679 Arrangements for the registration or de-registration of VLAN attribute values, e.g. VLAN identifiers, port VLAN membership

Abstract

A system in which a single VLAN architecture spans multiple VLAN transport protocols and technologies, including a method and system in which multiple different VLANs may be combined in a single enterprise network. Each LAN-switch in the system identifies each frame with an identifier, and associates that identifier with particular VLAN identifiers for each type of VLAN technology. When a frame is bridged or routed from a first type of VLAN to a second type of VLAN, the first VLAN encapsulation is removed and the second VLAN encapsulation is added, with appropriate change in the VLAN identifier for the frame or packet. The identifier may also be implicit for the frame, such as when a particular set of sender'"'"'s MAC addresses are identified with a particular VLAN. Individual VLANs, of whatever architecture, may be added, configured or reconfigured, modified, or deleted, using control tools associated with the multiple VLAN architecture system. Individual ports may be associated with particular VLANS, or may be designated “dynamic” so that frames or packets associated with those ports are associated with particular VLANs in response to source or destination addresses or other information.

Claims

1. A multiple VLAN architecture system, in which multiple different VLANs are capable of operating within a single network, comprising

at least one network communication medium;

a LAN-switch coupled to said at least one network communication medium and disposed to receive and route packets, each said packet having a VLAN identifier, and comprising means for routing from a first VLAN to a second VLAN, said means for routing comprising means for removing a first VLAN encapsulation and means for adding a second VLAN encapsulation, said means for adding said second VLAN encapsulation replacing said first VLAN encapsulation with said second VLAN encapsulation, said means for removing and said means for adding located at said LAN-switch; and

means for identifying said VLAN identifier and means for determining a new VLAN identifier for said second VLAN responsive thereto.

2. A multiple VLAN architecture system, in which multiple different VLANs are capable of operating within a single network, comprising

at least one network communication medium;

and

a LAN-switch coupled to said at least one network communication medium and disposed to receive and route packets, each said packet having a VLAN identifier, and comprising means for routing from a first VLAN to a second VLAN, said means for routing comprising means for removing a first VLAN encapsulation and means for adding a second VLAN encapsulation, said means for adding said second VLAN encapsulation replacing said first VLAN encapsulation with said second VLAN encapsulation, said means for removing and said means for adding located at said LAN-switch;

wherein said LAN-switch comprises a plurality of static ports, each said static port being associated with one of said VLANs.

3. A multiple VLAN architecture system, in which multiple different VLANs are capable of operating within a single network, comprising

a plurality of network communication media;

a first VLAN comprising a first plurality of devices, each one of said first plurality of devices coupled to at least one of said network communication media; and

a second VLAN comprising a second plurality of devices, each one of said second plurality of devices coupled to at least one of said network communication media;

said first plurality of devices and said second plurality of devices sharing at least one common device; and

said system further comprising;

means for receiving a packet having a first encapsulation according to said first VLAN;

means for removing said first encapsulation;

means for re-encapsulating said packet with a second encapsulation according to said second VLAN; and

means for receiving a packet from a source coupled to said first VLAN and transmitting said packet to a destination coupled to said second VLAN;

wherein said first encapsulation and said second encapsulation are substantially different, and said means for removing and said means for re-encapsulating are located at said at least one common device.

4. A multiple VLAN architecture system, in which multiple different VLANs are capable of operating within a single network, comprising

a plurality of network communication media;

a first VLAN comprising a first plurality of devices, each one of said first plurality of devices coupled to at least one of said network communication media; and

a second VLAN comprising a second plurality of devices, each one of said second plurality of devices coupled to at least one of said network communication media;

said first plurality of devices and said second plurality of devices sharing at least one common device; and

said system further comprising;

means for receiving a packet having a first encapsulation according to said first VLAN;

means for removing said first encapsulation;

means for re-encapsulating said packet with a second encapsulation according to said second VLAN; and

means for defining a new VLAN comprising a new corresponding plurality of devices, each one of said new corresponding plurality of devices coupled to at least one of said network communication media;

wherein said first encapsulation and said second encapsulation are substantially different, and said means for removing and said means for re-encapsulating are located at said at least one common device.

5. A method for routing a packet in a multiple VLAN architecture system, in which multiple different VLANs are capable of operating within a single network having at least one network communication medium, said system including a LAN-switch coupled to said at least one network communication medium and disposed to receive and route said packet, said packet having a VLAN identifier, said LAN-switch performing the step of:

routing said packet from a first VLAN to a second VLAN by;

removing a first VLAN encapsulation; and

replacing said first VLAN encapsulation with a second VLAN encapsulation;

wherein said LAN-switch includes a plurality of ports; and

wherein said plurality of ports include at least one dynamic port, and said method further includes steps of;

associating said at least one dynamic port with a first one of said VLANs; and

reassociating said at least one dynamic port with a second one of said VLANs.

6. A method for routing a packet in a multiple VLAN architecture system, in which multiple different VLANs are capable of operating within a single network having a plurality of network communication media, said system including a first VLAN comprising a first plurality of devices and a second VLAN comprising a second plurality of devices, each one of said second plurality of devices coupled to at least one of said network communication media, said first plurality of devices and said second plurality of devices sharing at least one common device, said at least one common device performing the steps of:

receiving a packet having a first encapsulation according to said first VLAN;

removing said first encapsulation;

re-encapsulating said packet with a second encapsulation according to said second VLAN, wherein said first encapsulation and said second encapsulation are substantially different; and

defining a new VLAN comprising a new corresponding plurality of devices, each one of said new corresponding plurality of devices coupled to at least one of said network communication media.

7. An apparatus having a central processing unit (CPU) and a memory coupled to said CPU for switching a packet between a plurality of different VLAN segments operational within a single network having one or more VLANs and one or more management domains, each management domain for management of at least one VLAN, the apparatus including:

a network interface in communication with at least one network communication medium and with said CPU;

a packet reception mechanism configured to receive said packet from said at least one network communication medium using the network interface, said packet having a VLAN identifier and originating from a first VLAN segment;

a packet routing mechanism configured to route said packet to a second VLAN segment; and

a VLAN configuration mechanism configured to maintain said one or more management domains in said apparatus, wherein the VLAN configuration mechanism includes;

a case detection mechanism configured to detect when to request an advertisement message;

a request advertisement mechanism, responsive to the case detection mechanism, configured to send an advert-request message over said at least one network communication medium;

an advertisement reception mechanism configured to receive said advertisement message from said at least one network communication medium; and

a configuration maintenance mechanism, responsive to changes in said one or more management domains, configured to maintain a configuration revision number for each of said one or more management domains.

8. The apparatus of claim 7 wherein said advert-request message includes:

an advert-request identification value in a type of message field; and

a management domain identification value of said apparatus in a management domain field.

9. The apparatus of claim 8 wherein said advert-request message further includes:

a start field containing a VLAN selection value that controls which of said one or more VLANS respond to said advert-request message.

10. The apparatus of claim 7 wherein the case detection mechanism is responsive to a condition selected from the group consisting of:

a condition of the apparatus initializing;

a condition of the apparatus having received one of a set of advertisement subset messages having a configuration value higher than said configuration revision number;

a condition of the apparatus having received an advertisement summary message having a configuration value higher than said configuration revision number without a subsequent one of a set of advertisement subset messages;

a condition of the apparatus having not received each of a set of advertisement subset messages as specified by an advertisement summary message;

or

a condition of the apparatus having received an advertisement summary message having a configuration value more than one higher than said configuration revision number.

11. The apparatus of claim 7 wherein said advertisement message includes:

an advertisement summary message; and

a set of advertisement subset messages;

wherein each message has a type of message field and a type of message field.

12. The apparatus of claim 11 wherein said advertisement summary message includes:

an advertisement summary message identification value, in said type of message field, that identifies said advertisement summary message;

a management domain identification value of a source of said advertisement summary message in said management domain field;

a followers value, in a followers field, that specifies a number of said set of advertisement subset messages related to said advertisement summary message; and

a configuration value, in a configuration revision number field, that identifies a configuration state for the source of said advertisement summary message.

13. The apparatus of claim 11 wherein each of said set of advertisement subset messages includes:

an advertisement subset message identification value, in said type of message field, that identifies said advertisement subset message;

a configuration value, in a configuration revision number field, that identifies the configuration state for a source of the advertisement subset message;

a sequence value, in a sequence number field, that distinguishes each of said set of advertisement subset messages; and

a set of VLAN block specific information for the VLANs advertised by the source of said advertisement subset messages.

14. An apparatus having a central processing unit (CPU) and a memory coupled to said CPU for switching a packet between a plurality of different VLAN segments operational within a single network having one or more VLANs and one or more management domains, each management domain for management of at least one VLAN, the apparatus including:

a network interface in communication with at least one network communication medium and with said CPU;

a packet reception mechanism configured to receive said packet from said at least one network communication medium using the network interface, said packet having a VLAN identifier and originating from a first VLAN segment;

a packet routing mechanism configured to route said packet to a second VLAN segment; and

a VLAN configuration mechanism configured to maintain said one or more management domains in said apparatus, wherein the VLAN configuration mechanism includes;

a case detection mechanism configured to detect when to send an advertisement message;

a send advertisement sending mechanism, responsive to the case detection mechanism, configured to send an advertisement message over said at least one network communication medium;

an advert-request message reception mechanism configured to receive an advert-request message from said at least one network communication medium; and

a configuration maintenance mechanism, responsive to changes in said one or more management domains, configured to maintain a configuration revision number for each of said one or more management domains.

15. The apparatus of claim 14 wherein the case detection mechanism is responsive to a condition selected from the group consisting of:

a condition of the apparatus having modified said configuration revision number;

a condition of an expiration of a timer without the apparatus having sent said advertisement message or the apparatus having received another advertisement message from said at least one network communication medium;

or

a condition of receipt of said advert-request message by the advert-request message reception mechanism.

16. A computer program product including:

a computer usable storage medium having computer readable code embodied therein for causing a computer to switch a packet between a plurality of different VLAN segments operational within a single network having one or more VLANs and one or more management domains, each management domain for management of at least one VLAN, said computer readable code including;

computer readable program code configured to cause said computer to effect a network interface in communication with at least one network communication medium and with said CPU;

computer readable program code configured to cause said computer to effect a packet reception mechanism configured to receive said packet from said at least one network communication medium using the network interface, said packet having a VLAN identifier and originating from a first VLAN segment;

computer readable program code configured to cause said computer to effect a packet routing mechanism configured to route said packet to a second VLAN segment; and

computer readable program code configured to cause said computer to effect a VLAN configuration mechanism configured to maintain said one or more management domains in said product, wherein the VLAN configuration mechanism includes;

computer readable program code configured to cause said computer to effect a case detection mechanism configure to detect when to request an advertisement message;

computer readable program code configured to cause said computer to effect a request advertisement mechanism, responsive to the case detection mechanism, configured to send an advert-request message over said at least one network communication medium;

computer readable program code configure to cause said computer to effect an advertisement reception mechanism configured to receive said advertisement message from said at least one network communication medium; and

computer readable program code configured to cause said computer to effect a configuration maintenance mechanism, responsive to changes in said one or more management domains, configured to maintain a configuration revision number for each of said one or more management domains.

17. The product of claim 16 wherein the case detection mechanism is responsive to a condition selected from the group consisting of:

a condition of the product initializing;

a condition of the product having received one of a set of advertisement subset messages having a configuration value higher than said configuration revision number;

a condition of the product having received an advertisement summary message having a configuration value higher than said configuration revision number without a subsequent one of a set of advertisement subset messages;

a condition of the product having not received each of a set of advertisement subset messages as specified by an advertisement summary message;

or

a condition of the product having received an advertisement summary message having a configuration value more than one higher than said configuration revision number.

18. A computer program product including:

a computer usable storage medium having computer readable code embodied therein for causing a computer to switch a packet between a plurality of different VLAN segments operational within a single network having one or more VLANs and one or more management domains, each management domain for management of at least one VLAN, said computer readable code including;

computer readable program code configured to cause said computer to effect a network interface in communication with at least one network communication medium and with said CPU;

computer readable program code configured to cause said computer to effect a packet reception mechanism configured to receive said packet from said at least one network communication medium using the network interface, said packet having a VLAN identifier and originating from a first VLAN segment;

computer readable program code configured to cause said computer to effect a packet routing mechanism configured to route said packet to a second VLAN segment; and

computer readable program code configured to cause said computer to effect a VLAN configuration mechanism configured to maintain said one or more management domains in said product, wherein the VLAN configuration mechanism includes;

computer readable program code configured to cause said computer to effect a case detection mechanism configured to detect when to send an advertisement message;

computer readable program code configured to cause said computer to effect a send advertisement sending mechanism, responsive to the case detection mechanism, configured to send an advertisement message over said at least one network communication medium;

computer readable program code configured to cause said computer to effect an advert-request message reception mechanism configured to receive an advert-request message from said at least one communication medium; and

computer readable program code configured to cause said computer to effect a configuration maintenance mechanism, responsive to changes in said one or more management domains, configured to maintain a configuration revision number for each of said one or more management domains.

19. The product of claim 18 wherein the case detection mechanism is responsive to a condition selected from the group consisting of:

a condition of the product having modified said configuration revision number;

a condition of an expiration of a timer without the product having sent said advertisement message or the product having received another advertisement message from said at least one network communication medium;

or

a condition of receipt of said advert-request message by the advert-request message reception mechanism.

20. A multiple VLAN architecture in which multiple different VLANs are capable of operating within a single network, comprising

at least one network communication medium;

and

a LAN-switch coupled to said at least one network communication medium and disposed to receive and route packets, each said packet having a VLAN identifier, and comprising means for routing from a first VLAN to a second VLAN, said means for routing comprising means for removing a first VLAN encapsulation and means for adding a second VLAN encapsulation, said means for adding said second VLAN encapsulation replacing said first VLAN encapsulation with said second VLAN encapsulation, said means for removing and said means for adding located at said LAN-switch;

wherein said LAN-switch comprises a plurality of ports; and

wherein said plurality of ports include at least one dynamic port which is associated with a first one of said VLANs and includes means for being reassociated with a second one of said VLANs.