On 11-07-2012 11:40, Paul Boven wrote:
Hi Freek,
On 07/11/2012 11:30 AM, Freek Dijkstra wrote:
I disagree, to me the VLAN is part of the header, not of the data stream. I presume that the actual end-user submits his/hers data to the network without VLAN, even though by the time it reaches the first STP the network provider will likely added a VLAN to the data.
As an end-user, I can tell you we have a differing view here: one of the things that makes NSI attractive to us is having the ability to aggregate multiple lightpaths on each 10G link between us and our NREN, by using VLAN tags. So I am assuming that the traffic leaves/arrives tagged at the end user. Please also take note of how SURFnet intends to use 'Multi Service Ports' in the SURFnet-7 that is currently being rolled out.
For clarification: I was not implying that you MUST NOT use VLAN tags at the end-site. In fact, I am well aware of your setup, and how useful this ability is. What I was commenting on is if the VLAN ID may or may not be changed along the way. For example, I have some connection with NORDUnet which they tag as VPLS 1000, and arrives with C-VLAN ID 1000 at Netherlight. Since that VLAN is already is use with SARA, NetherLight retags it to VLAN 2001. I combined Henriks comment that the "VLAN [ID] is part of the data [stream]" with my personal mantra "don't alter the customers data stream" as to read "don't ever change the VLAN ID", and I disagreed with that. Hope this clarifies things. What do you think, may a NSI network alter the VLAN ID ("swap label") along the way? Freek