Protocol stack G.hn

g.hn protocol stack

g.hn specifies physical layer , data link layer, according osi model.

the g.hn data link layer (recommendation g.9961) divided 3 sub-layers:

the application protocol convergence (apc) layer, accepts frames (usually in ethernet format) upper layer (application entity) , encapsulates them g.hn apc protocol data units (apdus). maximum payload of each apdu 2 bytes.
the logical link control (llc), responsible encryption, aggregation, segmentation , automatic repeat-request. sub-layer responsible relaying of apdus between nodes may not able communicate through direct connection.
the medium access control (mac), schedules channel access.


the g.hn physical layer (recommendation g.9960) divided 3 sub-layers:

the physical coding sub-layer (pcs), responsible generating phy headers.
the physical medium attachment (pma), responsible scrambling , forward error correction coding/decoding.
the physical medium dependent (pmd), responsible bit-loading , ofdm modulation.

the pmd sub-layer sub-layer in g.hn stack medium dependent (i.e., parameters may have different values each media - power lines, phone lines , coaxial cable). rest of sub-layers (apc, llc, mac, pcs , pma) medium independent .

the interface between application entity , data link layer called a-interface. interface between data link layer , physical layer called medium independent interface (mii). interface between physical layer , actual transmission medium called medium dependent interface (mdi).