patchlwIP - A Lightweight TCP/IP stack - Patches: patch #7993, Add support for transmitting...


You are not allowed to post comments on this tracker with your current authentication level.

patch #7993: Add support for transmitting packets with VLAN headers

Submitter:  Fatih Aşıcı <fatih>
Submitted:  Wed 03 Apr 2013 08:52:42 AM UTC
Category:  None Priority:  5 - Normal
Status:  Done Privacy:  Public
Assigned to:  goldsimon Open/Closed:  Closed
Planned Release:  None

Thu 20 Feb 2014 08:11:19 PM UTC, comment #5: 

Right. Done as in the patch, thanks for it.

Simon Goldschmidt <goldsimon>
Group administrator
Mon 20 Jan 2014 01:11:49 PM UTC, comment #4: 

I don't have a broad knowledge on the purpose of VLAN priority. Without this patch, it was impossible to get connection with the uplink port of a switch used in the project which I was working for at that time.

I am not sure whether adding this info per pcb is a simple task.

Fatih Aşıcı <fatih>
Sat 18 Jan 2014 09:38:00 PM UTC, comment #3: 

There are industrial automation protocols which do rely on the application influencing the priority. The next switch is of course not obliged to take over this priority setting, but in an automation network with correctly configured switches, it does.

This might be a different thing for non-automation-network devices, of course, where the network maintainer wants to stay in control over prioritization...

Simon Goldschmidt <goldsimon>
Group administrator
Fri 17 Jan 2014 10:50:27 PM UTC, comment #2: 

The Class of Service (CoS) field is separate from DiffServ/DSCP. I don't think anything at the IP layer should influence the 802.1q CoS.

I'm not sure it even makes sense for an end device to apply a VLAN CoS. A switch would probably just ignore it and reapply its own CoS value, depending on what the network administrator has configured for that VLAN's priority.

Typically I'd think the 802.1q header should be applied at the interface level, but I think this patch might be OK for a lightweight environment.

I just had to respond to this because I'd hate to see upper-layer PCBs influence the 802.1q CoS.

Mike Pontillo <pontillo>
Fri 17 Jan 2014 09:38:33 PM UTC, comment #1: 

I'm not sure this is the right approach. It might be for the VLAN ID, but the priority rather depends on the actual packet to be sent. I think adding this per pcb would be a better approach. This way, you could prevent adding a VLAN header to all packets, even if the VLAN ID and priority stay at 0.

Simon Goldschmidt <goldsimon>
Group administrator
Wed 03 Apr 2013 08:52:42 AM UTC, original submission:  

Fatih Aşıcı <fatih>


(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)


Depends on the following items: None found

Items that depend on this one: None found


Carbon-Copy List
  • -email is unavailable- added by pontillo (Posted a comment)
  • -email is unavailable- added by goldsimon (Posted a comment)
  • -email is unavailable- added by fatih (Submitted the item)

    There are 0 votes so far. Votes easily highlight which items people would like to see resolved in priority, independently of the priority of the item set by tracker managers.


    Follow 5 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2014-02-20 goldsimon StatusWont Do Done
        Assigned toNone goldsimon
        Open/ClosedOpen Closed
    2014-01-17 goldsimon StatusNone Wont Do
    2013-04-03 fatih Attached File- Added Add-support-for-transmitting-packets-with-VLAN-heade.patch, #27752

    Back to the top

    Powered by Savane 3.13-4448.
    Corresponding source code