Assumption for flow:
Ethernet connection between two nodes through switches/bridges only
- No VLAN (802.1Q) header
- VLAN having same ID and priority (same PCP, DEI, and VID)
May frame reordering (misordering) then occur, or is it safe to assume that frames for the flow are received in same order as transmitted?
Background for question: I am implementing a hardware module that handles Ethernet frames at L2 level, and I consider whether I can safely assume that frames are not reordered when going from the source to destination through switches/bridges. The network is assumed to be a star topology, thus without loops, so based on this I assume that the comment in "K.3 Frame misordering" below does not apply, since there is no possibility for change of topology through e.g. STP/RSTP.
Standard information: From "802.1D-2004 Media Access Control (MAC) Bridges":
6.3.3 Frame misordering
The MAC Service (9.2 of ISO/IEC 15802-1) permits a negligible rate of reordering of frames with a given user priority for a given combination of destination address and source address.
K.3 Frame misordering
A change in the active topology between two communicating end stations can result in frame misordering, as a frame sent after reconfiguration can experience a lower transit delay, being queued at fewer Bridge Ports or for less time.