Tag switching (4)
Modules to support routing functions
- in hierarchical routing, within a domain routing is provided via interior routing (e.g. OSPF), while routing access domains is provided via exterior routing (e.g. BGP)
- tag switching allows the decoupling of interior and exterior routing
- packets can carry no ONE but a set tags organized as a stack
- in multicast routing , multicast routing procedures (e.g.PIM) are responsible for constructing spanning trees, with receivers as leaves
- tag switch supports multicast by utilizing data-link layer multicast capabilities
QoS is a tag switch capability based on
- classification of packets into different classes
- handling of packets via appropriate QoS characteristics