The main basic functions of the aggregation layer are:

1. Convergence of user traffic at the access layer, aggregation, forwarding and exchange of data packet transmission;

< p>2. Based on user traffic at the access layer, perform local routing, filtering, traffic balancing, QoS priority management, security mechanisms, IP address translation, traffic shaping, multicast management, etc.;

3. Forward user traffic to the core switching layer or perform routing processing locally based on the processing results;

4. Complete the conversion of various protocols (such as routing summary and re-publication, etc.) to ensure that the core layer Connect areas running different protocols.