US6680945B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for support of tagging and untagging per VLAN per port
Assignee: GlobalFoundries Inc
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Filing: 1999-05-24
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Granted: 2004-01-20
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Expires: 2019-05-24
Abstract
Abstract An integrated multiport switch operating in a packet switched network provides the capability via distributed egress logic to alter VLAN tags on a port by port basis. An internal rules checker (IRC) analyzes the header of a data frame to determine the frame type: untagged, VLAN-tagged, or priority-tagged. The IRC searches the untagged set table for the set of ports that are untagged for a particular VLAN. The IRC passes a forwarding descriptor that includes the frame type and a operational code (opcode) to a Port Vector FIFO logic (PVF). The PVF is responsible for creating a new opcode that instructs a dequeuing logic to add, remove, modify the VLAN tag, or send the frame unmodified. The opcodes generated by the PVF are individualized for each output port.
Inventors
- 👤 Shashank Merchant
- 👤 Robert A. Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:38
CPC Classifications
H; H04; H04L; H04L45/00; H04L12/00; H04L12/28; H04L12/46; H04L12/4641; H04L12/4645; H04L12/467; H04L45/50
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
176 words
A multiport switch configured for transferring a data frame to a network node, comprising: a plurality of output ports for transmitting the data frame; rules checker logic for determining a type of data frame based upon header information associated with the data frame and for generating a corresponding forwarding descriptor; and port logic for receiving the forwarding descriptor and for generating a modified forwarding descriptor in response to the received forwarding descriptor, the modified forwarding descriptor comprising an operation code indicating a tag operation for modifying the data frame based upon the frame type and untagged set information, the untagged set information specifying on a VLAN by VLAN basis which one or more of the output ports is a member of an untagged set; wherein the tag operation comprises one of: inserting a VLAN tag into the header information, stripping the VLAN tag from the header information, modifying the VLAN tag of the header information, and transmitting the data frame via one or more of the outputs without modifying the VLAN tag of the header information.
Claim 2
Dependent Claim
176 words
A multiport switch configured for transferring a data frame to a network node, comprising: a plurality of output ports for transmitting the data frame; rules checker logic for determining a type of data frame based upon header information associated with the data frame and for generating a corresponding forwarding descriptor; and port logic for receiving the forwarding descriptor and for generating a modified forwarding descriptor in response to the received forwarding descriptor, the modified forwarding descriptor comprising an operation code indicating a tag operation for modifying the data frame based upon the frame type and untagged set information, the untagged set information specifying on a VLAN by VLAN basis which one or more of the output ports is a member of an untagged set; wherein the tag operation comprises one of: inserting a VLAN tag into the header information, stripping the VLAN tag from the header information, modifying the VLAN tag of the header information, and transmitting the data frame via one or more of the outputs without modifying the VLAN tag of the header information.
Claim 3
Dependent Claim
43 words
The multiport switch as in claim 1 , wherein each of the output ports is coupled to a corresponding dequeuing logic, the dequeuing logic being configured for receiving the modified forwarding descriptor from the port logic and for executing the corresponding tag operation.
Claim 4
Dependent Claim
52 words
The multiport switch as in claim 1 , wherein types of data frame comprise an untagged type indicating that the data frame does not include a VLAN tag, a priority-tagged type indicating that the data frame has queuing priority, and a VLAN-tagged type indicating that the data frame includes a VLAN tag.
Claim 5
Dependent Claim
150 words
The multiport switch as in claim 3 , wherein the operation code indicates the tag operation of: inserting the VLAN tag if the data frame is of the untagged type and a corresponding one of the output ports is not a member of the untagged set; stripping the VLAN tag if the data frame is of the priority-tagged type or VLAN-tagged type and the corresponding one of the output ports is a member of the untagged set; modifying the VLAN tag if the data frame is of the priority-tagged type and the corresponding one of the output ports is not a member of the untagged set; or transmitting the data frame via the corresponding one of the output ports without modifying the VLAN tag if the data frame is of the VLAN tagged type and the corresponding one of the output ports is not a member of the untagged set.
Claim 6
Dependent Claim
20 words
The multiport switch as in claim 1 , further comprising a untagged set table for storing the untagged set information.
Claim 7
Dependent Claim
22 words
The multiport switch as in claim 5 , wherein the untagged set table is managed by a host central processing unit (CPU).
Claim 8
Dependent Claim
33 words
The multiport switch as in claim 1 , wherein the VLAN tag comprises a VLAN Tag Protocol Identifier (TPID) field and a Tag Control Information (TCI) field in compliance with IEEE 802.1d standard.
Claim 9
Independent Claim
163 words
A method for processing a data frame, comprising the steps of: determining data frame type based upon header information associated with the data frame and generating a corresponding forwarding descriptor by a first logic; receiving the forwarding descriptor a second logic; and generating a modified forwarding descriptor based upon the received forwarding descriptor by the second logic, the modified forwarding descriptor comprising an operation code indicating a tag operation for modifying the data frame based upon the frame type and untagged set information, the untagged set information specifying on a VLAN by VLAN basis which one or more of a plurality of output ports is a member of an untagged set; wherein the tag operation comprises one of: inserting the VLAN tag into the header information, stripping the VLAN tag from the header information, modifying the VLAN tag of the header information, and transmitting the data frame via one or more of the outputs without modifying the VLAN tag of the header information.
Claim 10
Independent Claim
163 words
A method for processing a data frame, comprising the steps of: determining data frame type based upon header information associated with the data frame and generating a corresponding forwarding descriptor by a first logic; receiving the forwarding descriptor a second logic; and generating a modified forwarding descriptor based upon the received forwarding descriptor by the second logic, the modified forwarding descriptor comprising an operation code indicating a tag operation for modifying the data frame based upon the frame type and untagged set information, the untagged set information specifying on a VLAN by VLAN basis which one or more of a plurality of output ports is a member of an untagged set; wherein the tag operation comprises one of: inserting the VLAN tag into the header information, stripping the VLAN tag from the header information, modifying the VLAN tag of the header information, and transmitting the data frame via one or more of the outputs without modifying the VLAN tag of the header information.
Claim 11
Dependent Claim
21 words
The method as in claim 8 , wherein the first logic in the step of determining is a rules checker logic.
Claim 12
Dependent Claim
22 words
The method as in claim 8 , wherein the second logic in the steps of receiving and generating is a port logic.
Claim 13
Dependent Claim
38 words
The method as in claim 8 , wherein each of the output ports is coupled to a corresponding dequeuing logic, the dequeuing logic being configured for receiving the modified forwarding descriptor and for executing the corresponding tag operation.
Claim 14
Dependent Claim
51 words
The method as in claim 8 , wherein types of data frame comprise an untagged type indicating that the data frame does not include a VLAN tag, a priority-tagged type indicating that the data frame has queuing priority, and a VLAN-tagged type indicating that the data frame includes a VLAN tag.
Claim 15
Dependent Claim
149 words
The method as in claim 12 , wherein the operation code indicates the tag operation of: inserting the VLAN tag if the data frame is of the untagged type and a corresponding one of the output ports is not a member of the untagged set; stripping the VLAN tag if the data frame is of the priority-tagged type or VLAN-tagged type and the corresponding one of the output ports is a member of the untagged set; modifying the VLAN tag if the data frame is of the priority-tagged type and the corresponding one of the output ports is not a member of the untagged set; or transmitting the data frame via the corresponding one of the output ports without modifying the VLAN tag if the data frame is of the VLAN tagged type and the corresponding one of the output ports is not a member of the untagged set.
Claim 16
Dependent Claim
19 words
The method as in claim 8 , further comprising storing the untagged set information in an untagged set table.
Claim 17
Dependent Claim
21 words
The method as in claim 14 , wherein the untagged set table is managed by a host central processing unit (CPU).
Claim 18
Dependent Claim
32 words
The method as in claim 8 , wherein the VLAN tag comprises a VLAN Tag Protocol Identifier (TPID) field and a Tag Control Information (TCI) field in compliance with IEEE 802.1d standard.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-01-19 | 2007-07-21 | 2008-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-01-19 | 2011-07-21 | 2012-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-01-19 | 2015-07-21 | 2016-01-20 | $7700.00 | Window Closed / Lapsed |