This document discusses group communication. It begins by stating that RPC only allows communication between two parties, whereas sometimes multiple processes need to communicate with each other, which RPC cannot handle. An example given is a group of file servers cooperating to provide a fault-tolerant file service. The document then defines group communication as one-to-many communication, and notes that groups are dynamic - new groups can form and old groups can disband, and processes can join or leave groups. The purpose of group communication is to allow processes to interact with collections of other processes as a single entity.

1. Introduction to Group Communication
 RPC involves only two parties, the client and server.
 Sometimes we need multiple processes to communication among each
others. RPC cannot handle this.
 For example, a group of file servers co-operating to offer a single, fault
tolerant file service.
 Group Communication:
 one-to-many other than one-to-one communication
 Groups are dynamic:
 New groups can be created and old groups can be destroyed.
 A process can join a group or leave one.
 A process can be a member of several groups at the same time.
 The purpose of introducing groups is to allow processes to deal with
collections of processes as a single abstraction. Thus, a process can send
a message to a group of servers without having to know how many there
are or where they are.

2. Meaning and Definition of
Group
A group consists of two or more persons who
interact with each other, consciously for the
achievement of certain common objectives. The
members of the group are inter-dependent and are
aware that they are part of a group.

3. Characteristics of a Group
Social Interaction
 Stable Structure
Common Interest
Perceive Themselves as Part of Group

4. Social Interaction:One of the most obvious characteristics of group is. In
other words, the members of group must have influthat they are composed of
two or more people in social interactionence on each other.The interaction
between parties may either verbal on non-verbal, but the parties must have
some impact on each other to be considered as a group.
Stable Structure:Group also must posses a stable structure. Although groups
can change, and often do, there must be some stable relationships that keep
group members together and functioning as an unit.
Common Interest:The formulation of a group is closely related to some
common goals or purpose. The achievement of common goals of a group is
a matter of common concern for every member and they have an obligation
to contribute for attaining the common goals.
Perceive Themselves as Part of Group:Finally, to be a group, the individuals
involved must perceive themselves as a group. Group is composed of people
who recognize each other as a member of their group and can distinguish
these individuals from non-members.

5. Importance of Group
Communication
1. Wide Knowledge:
2. Diversity of Views
3. Acceptance
4. Legitimacy

6. 1) Wide Knowledge: Groups permit to pool more detailed information
and knowledge. They constitute crucial
impulse for sound decision-making. The aggregation of ideas of
several individuals helps to make quality
and sound decision.
2) Diversity of Views: There is no scope in group deliberations for any
homogeneity of ideas. Groups permit
not only more knowledge and information as input but it can bring
heterogeneity in the decision-making
process. Several alternatives can be considered and the best
possible solutions can be arrived at.
3) Acceptance: In addition to heterogeneity to the decision-making
group, decisions are accepted for
implementation. Increased acceptance of solution is possible, people
concerned with the decisions will be
more likely to accept it and encourage others. There is a support and
backing for group decision.
4) Legitimacy: In a democratic set-up, group decisions are based on
the principles of democracy. Group
decisions are more consistent with democratic ideas. These are
therefore, legitimate than decisions made
by a single person. A single person’s decision is known for its
autocracy and arbitrariness.

7. Name: Patel Vivek
Enrollment no: 13010125089
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