Chapter 4
SCALABLE RECURSIVE
MULTICAST PROTOCOL
Scalable Recursive Multicast protocol (SReM) is a novel scalable multicast protocol for fixed
network which will be discussed in details at this chapter. This discussion will include a
detailed description of this protocol as well as the simulation environment, scenarios and
metrics used to evaluate its performance for this protocol. Finally the output results will be
presented and evaluated.
4.1 Introduction
Due to the scarce resources in the Internet, multicast provides an efficient solution to use
these recourses fully and efficiently. Because of the explosive increasing in traffic over the
Internet, multicasting became an important issue in routing protocols [66, 6]. Some issues
are still open such as scalability [26], billing [25], address allocation [8] and security [44],
where the scalability has drawn much attention for Internet application.
The main issue that causes the scalability problem is the increasing demand on the Multicast
Forwarding Table (MFT) because of the increase in multicast group members or the increase
in the number of multicast groups. So there are two main aspects that can be used to evaluate
the scalability in multicast protocols: scalability with regard to the number of group
members and to the number of multicast groups in the network. Recently, there are a number
of proposed mechanisms to solve the scalability issue in multicast protocols, which can be
categorized into tunnelling techniques, forwarding state reduction and explicit multicast. Our
research falls in the explicit multicast mechanism; a detailed discussion for this mechanism
was performed in the previous chapter.
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