User's Manual

3 Detailed Description
APCD-LM043-4.0 27
5. If the route to the destination is through the CCU Radio Port, then the CCU obtains the
destination Ethernet MAC address from the ARP Table, described in ARP Table (CCU
and EUM) on page 187. If the destination is not listed in the ARP Table, the CCU
obtains its MAC address by issuing an ARP query. Once it gets the MAC address, it
adds the entry to the ARP Table.
6. Using the destination Ethernet MAC address, the CCU obtains the EUM ID from the
Address Translation Table, described in Address Translation Table (CCU only) on
page 188.
7. Using the EUM ID, the CCU obtains the EUM grade of service from the Registration
Table, described in Registration Table (CCU only) on page 190.
8. The IP packet is then transmitted through the Polling MAC and radio interface to the
EUM.
9. The EUM receives the packet through the EUM radio port and checks the port
number. If the port number appears in the EUM Port Filter Table, the packet is
discarded.
10. If the port number does not appear in the EUM Port Filter Table, the EUM checks the
destination MAC address. If the MAC address is the EUM MAC address, then the
packet is forwarded to the EUM application; otherwise, the IP packet is sent out
through the Ethernet port to the end user’s equipment.
End-user Computer to Internet Data Transmission
1. The EUM receives IP packets from the end-user’s equipment through the Ethernet
port.
2. The EUM checks the port number. If the port is listed in the EUM Port Filter Table, the
packet is discarded.
3. If it is not already in the list, the EUM adds the source Ethernet address to the
Customer Table, described in Customer Table (EUM only) on page 192. The EUM
determines whether or not the source is entitled to air access, based on the Customer
Table.
4. If the source is not entitled to air access, the packet is discarded.
5. The EUM checks the destination MAC address. If the destination MAC address
appears in the Customer Table, meaning the destination is on the Ethernet side, the
packet is discarded.
6. If the destination MAC address is the same as the EUM MAC address, then the
packet is forwarded to the EUM application; otherwise, it is forwarded through the
polling MAC and radio link to the CCU.
7. The CCU receives the packet through the CCU radio port. The CCU either updates or
adds the Ethernet address to the Address Table.
8. The CCU checks the port number. If the port number appears in the CCU Port Filter
Table, the packet is discarded.
9. The CCU checks the destination MAC address. If the destination MAC address is not
in the Address Table, the packet is sent to the CCU router application.