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

4-June-07 P1901_PRO_016_r0
Point-to-point ports and edge ports
In order to achieve fast convergence on a port, the protocol relies upon two new variables: edge ports and link type.
All BPL ports can be assumed to be point-to-point ports. Ethernet ports can be considered edge ports, unless another
bridge is connected to the same segment. Anyway, since the standard establishes that the first BPDU coming into an
edge port removes its edge port status, it can be assumed at startup that all ports are candidate to directly transition
to forwarding:
Ethernet ports start in forwarding state (edge ports).
BPL ports, even though they start in blocking state, are ready for handshake and rapid transition to forwarding
(point-to-point).
STP and VLANs
If VLANs are active, STP packets must use the management VLAN inside the power-line network.
Common STP
Ethernet interfaces must support the possibility of being configured to remove/add the VLAN tag to the
outgoing/incoming STP packets. That is, the VLAN tag of the STP packets going out the BPL network is removed.
On the other hand, VLAN tag must be added to the incoming STP packets, so as to make sure that STP packets
inside the power-line network use the management VLAN.
10 SECURITY
10.1 LOW LEVEL ENCRYPTION AND INTEGRITY
10.1.1 Overview
Encryption and Integrity are two key features needed by any communication device to guarantee security and
privacy in the message exchange.
For encryption IEEE P1901 uses as basic building block the Advanced Encryption Standard (AES) according to
FIPS-97(2002).
AES is a block cipher algorithm while higher layers have to deal with variable length packets. To be able to encrypt
these variable length packets IEEE P1901 uses the operation mode known as Counter Mode (CTR) defined in
Submission page 279 UPA-OPERA