1. TRILL Multi Topology Encoding and Nickname Expansion draft-tissa-trill-mt-encode-01 Tissa Senevirathne Naveen Nimmu Sam Aldrin

2. Objective No Changes to the TRILL header Ability to selectively include or exclude proposed extensions ◦Allow to interface with older RBridges Minimize or eliminate need for mapping of Topology ID space

3. Methodology Encode as part of the outer header Separate EtherType to demarcate Multi Topology ID Separate EtherType to demarcate Upper bits of nicknames

4. Encoding Outer Header EthType=X MT-ID EthType=YEG-NKIG-NK TRILL Header Inner Frame

5. Multi Topology Interoperability Older Rbridges belong only to a single topology New Rbridges selectively encode the MT- ID New RB Old RB New RB Encode MT-ID Do not Encode MT-ID MT Aware cloud Non MT Aware cloud They belong only to a single topology

6. Nickname Interoperability Green field deployments use entire 24bits. In mixed mode ◦Old RBridges in a different set of topologies ◦New RBridges in 24bit RBridge specific topologies ◦Old and new RBridges can not communicate, directly.