Hello All Again, As a follow up to what I mentioned earlier regarding the same packet on eth3 and eth3.2, I should also have mentioned the following: -When I monitor(using ethereal) just the eth3 I see a Tagged(VLAN) Packet being sent from it and it shows the source address as 51.1.2.2. However, when I monitor eth3.2 I see an UnTagged(no VLAN) Packet sent from it and it also shows the same source IP of 51.1.2.2. Should this not be the other way arround. I would expect the monitoring of eth3.2 to show VLAN and eth3 to UnTagged(no VLAN) packet. Does the internal Linux handling of the VLAN justify what I am seeing? Thanks, Cyprian. ------------- Cyprian Clement <cyprian_clement@xxxxxxxxxxx> wrote:Hi Ben, To answer your question, all I observe on the ethereal is as follows: Source Destination 51.1.2.2 51.1.20.2 51.1.2.2 51.1.20.2 Now when I click on one of them I see a packet with VLAN Tag but when I click on the second one I see exactly the same packet(same seq number, SSRC, and Timestamp) but without a Tag(i.e. without .1q). From this I deduce it's the same packet but sent differently. Not sure whether it's actually sent twice or once simply once but one of them is stripped off .1q Any Comments? Regards, Cyprian. ------------ Ben Greear <greearb@xxxxxxxxxxxxxxx> wrote: Cyprian Clement wrote: > Hello community, > > > > I have a query regarding packet transmission in the VLAN arena. First, > let me give a picture of the configuration I have: > > > > Eth3 eth4 > > Eth3.2 eth4.2 > > > > I have assigned eth3.2 an IP of 51.1.2.2 and eth4.2 an IP of 51.1.20.2 > > > > A call is made from 51.1.2.2(i.e. eth3.2) to 51.1.20.2(i.e. eth4.2). The > issue I have noted is that when monitoring a call via ethereal I see > that the same RTP packet is being sent twice. However, one of the packet > is has a VLAN Tag while the other one has no Tag but both of them go to > the same address. > > > > -The question is why is this the case? i.e. why do we have same packet > t! wice; one Tagged while the other Untagged? > > -Is it fair to assume that the Tagged packet goes to eth4.2 while the > Untagged one goes to eth4 ? > > -If this is the case does it mean eth3.2 originates the same packet > twice? Or it?s simply that the same packet is being sent twice but one > by eth3(Untagged) and the other by eth3.2(Tagged) ? I wonder why this > would be the case though. Are you sure it's being sent twice, or are you watching the same packet traverse the .1q interface and then the physical interface on the way to the wire? Ben > > > > As always, Thank you in advance. > > > > Regards, > > > > Cyprian. > > ------------ > > Send instant messages to your online friends http://uk.messenger.yahoo.com > > > ------------------------------------------------------------------------ > > _______________________________________________ > Vlan mailing list > Vlan@xxxxxxxxxxxxxxx > http://www.lanforge.com/mailman/listinfo/vlan -- Ben Greear Candela Technologies Inc http://www.candelatech.com _______________________________________________ Vlan mailing list Vlan@xxxxxxxxxxxxxxx http://www.lanforge.com/mailman/listinfo/vlan Send instant messages to your online friends http://uk.messenger.yahoo.com _______________________________________________ Vlan mailing list Vlan@xxxxxxxxxxxxxxx http://www.lanforge.com/mailman/listinfo/vlan Send instant messages to your online friends http://uk.messenger.yahoo.com -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.candelatech.com/pipermail/vlan/attachments/20050404/873e31cf/attachment.htm
