• SMT (Session Membership Table): - This table maintains the membership for a
given session.
• SFT (Session Forwarding Table):- This table maps the destinations to their next hop.
Nodes with the same next hop are grouped together.
• XFT (eXplicit Forwarder Table):- Nodes working as a XFs and their downstream
session members.
The source node maintains SMT for the members of each session and also for each session
the XFT stores all XFs to their corresponding list of destinations addresses. The source
maintains the SFT by grouping the group members to their respective next hop. This SFT is
further divided into subsets according to their next hops. Each XF maintains both SFT and
SMT tables. XF does not need to maintain a XFT table. Figure 3.3 shows an example of E2M
packet delivery. Node A is the source node and nodes (B to G) are receivers, where N6 is an
XF. The MFT source contains the XFs and receivers to its next hop, in our example, MFT at
A contains N6 as an XF and B,C as receivers grouped to the next hop N1. Upon receiving the
data packet, N1 forward the packet to its next hop without any changes, N2 will act similarly
as the source did and sends two packets to its next hops. N6 will receive this packet and
depending in its XFT, it generates a number of packets and forwards these packets to its next
hops, the procedure continues until all receivers get the data packet.
Figure 3.3 E2M packet delivery [7]
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