Medium Access Control (MAC) and Physical Layer (PHY) - CISE

4-June-07 P1901_PRO_016_r0
Furthermore, there are MAC primitives to give the QoS scheduler an idea of the BPL topology. These primitives
collect information in the Upstream direction. These primitives allows to compute correctly the Validity field. These
parameters are:
• Maximum Number of Hops in the network
• Number of Downstream Nodes
9 LAYER MANAGEMENT
9.1 CONTROL PROTOCOLS
9.1.1 CCP (Communication Control Protocol) Description
The exchange of management messages between IEEE P1901 nodes needs a special and homogeneous structure in
order to simplify implementation and clarify information exchanges between nodes. Such information will have as
source and destination IEEE P1901 nodes, and will be used for internal management.
The structure of the packet that will be exchanged by two BPL nodes will follow the scheme presented in Figure 67:
TPID
DSAP
SSAP
CTL
OUI0
OUI1
OUI2
Type0
Type1
Length
Dest MAC Src MAC Payload
TCI
Figure 67 Management packet
The management information will be encapsulated using SNAP as depicted in Figure 67 into a regular Ethernet
Frame. Using SNAP with an assigned OUI, it is possible to create specific protocols for IEEE P1901 nodes.
Encapsulated fields will be described in the following table:
Field Length Description
Submission page 186 UPA-OPERA
Data
DSAP 1 byte Destination Service Access Point