Network Working Group                                                    Forest
Request for Comments: 12345                            Communication Center UBB
Category: Internet-drafts                                         December 2001



			 Hello Protocol -- HP/1.0

Status of this Memo

     This document specifies an Internet draft protocol for the
Internet community, and requests discussion and suggestions for
improvements.  Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.

Abstract

     The Hello Protocol (HP) is an application-level protocol designed to
help III-rd year students to learn the concept of Internet sockets. It is a
generic, very simplistic, connection-oriented protocol and its only purpose 
is the one mentined above.    

Table of Contents

   1 Introduction.................................................1
   2 Terminology..................................................2
   3 Specification................................................2
   4 Errors.......................................................2
   5 Final observations...........................................3



1 Introduction

     Being a simple protocol, designed only to serve as an example for
socket communication between two diferent machines, the Hello Protocol 
uses TCP (Transmission Control Protocol) as the transport layer protocol
and does perform error-checking at application level. The HP/1.0 
involves two machines, a client and a server. They perform simple
conversation, exchanging strings of maximum 255 characters without any 
special meaning.



Forest                      Internet-drafts                        [Page 2]

RFC 12345                        HP/1.0                       December 2001 



2 Terminology

     The two machines involved in the conversation are called the client (C)
and the server (S). The server will listen for connections on the standard 
port 12345 (P).

3 Specification

     The HP/1.0 is the basic specification for the "hello-conversation".
The server listen for connections on port P. When a client connects to the
port P, the server expects to receive a message of the form
                  HELLO;name
where name is an array of characters representing the name of the client. 
This name must be maximum 250 characters long. If the message does not begin
with the string "HELLO;", the server will reply with an 200 error message.
Otherwise, the server will send back to the client the message
                  HELLO name! Server is pleased to meet you.
where the string "Server" represents the name or the IP address of the
server. After the server sends this message, he will close the connection
with the client.    

4 Errors

     There is only one error message with error code of 200 and that is
                   Message not understood!
This error happens if the string received from the client doesn't begin
with "HELLO;"



Forest                      Internet-drafts                        [Page 3]

RFC 12345                        HP/1.0                       December 2001



5 Final observations 

     This protocol (HP/1.0) was born due to Andreea's (mail:deiush@cs.ubbcluj.ro)
complainings regarding the fact that the III-rd year Operating Systems
students don't have any written material that describes a very simple, easy
to understand socket communication. (The author of this memo hopes she's
happy now;)
     The port number (P) 12345 was initialy specified to be 1234, but Grigo
(mail:grigo@cs.ubbcluj.ro) for no particular reason changed it to 12345.
Happy coding!;)