Seitenhistorie

The circuit ID consists of three fields. Note that the circuit ID in the switch is already encoded in binary, but is expected by hexadecimal notation. As the router also expects the circuit ID in hexadecimal notation, it doesn't have to be converted. This can be seen in an Ethernet trace (filtered for BootP). For this reason In the router the circuit ID must be prefixed with the string 0x. Furthermore, the VID and the port number must be converted if necessary.  

1. vlan_id: Stands for the VLAN ID of the switch port. The field has four digits, so the entry could be 0010 000a for example.
2. module_id: Stands for the Module ID of the switch. For GS-3xxx switches this is always 00.
3. port_no: Stands for the Port number of the switch port. The field has two digits, so the entry could be 07 for example.

Example:

A network member in VLAN 10 and connected to port 7 should be given a specific IP address. The VID 10 is a in hexadecimal notation. The resulting circuit ID appears as follows: