Paul Barry 
Programming the Network with Perl 

After providing an introduction to the Perl programming language, this helpful guide teaches computer networking using Perl. Topics discussed include ethernet network analysis, programming standard Internet protocols, and exploring mobile agent programming.

* Each chapter provides a general discussion of the technologies under consideration, the support for programming the technologies as provided by Perl, and implementations of working examples

* Covers Mobile Agent Technology, which is set to become one of the ‘next big things’ on the Internet

* Further information is supplied, including a listing of Web and print resources, programming exercises, and tips to expand the reader’s understanding of the material

Table of Content

1. Meet Perl

Perl’s Default Behaviour

Using Variables in Perl

Controlling Flow

Boolean in Perl

Perl Operators

Subroutines

Perl I/O

Packages, Modules and Objects

More Perl

Where to From Here?

Print Resources

Web Resources

2. Snooping

Thank You, Tim Potter

Preparing to Snoop

Building Low-Level Snooping Tools

Snooping IP Datagrams

Transport Snoopers

The Network Debugger

Where to From Here?

Print Resources

Web Resources

3. Sockets

Clients and Servers

Transport Services

Introducing the Perl Socket API

Socket Support Subroutines

Simple UDP Clients and Servers

Genericity and Robustness

UDP is Unreliable

Sending and Receiving with UDP

Dealing with Deadlock

TCP Clients and Servers

A Common TCP Gotcha

More TCP Socket Communication

The Concurrent Syntax Checker

Object-Oriented Sockets

Where to From Here?

Print Resources

Web Resources

4. Protocols

Gotcha!

Working with the Web

The World’s Worst Web Browser

HTTP Status Codes

It’s the Gisle and Graham Show!

The Library for WWW Access in Perl

The LWPwwwb Program

Doing More with LWPwwwb

Building a Custom Web Server

The libnet Library

Email Enabling simplehttpd

Other Networking Add-on Modules

Where to From Here?

Print Resources

Web Resources

5. Management

Simple Management with ICMP

Doing the Ping Thing

Doing the Net: Ping Thing

Tracing Routes

Not So Simple Management with SNMP

The SNMP Management Framework

Managed Data

The SNMP Protocol

The Net: SNMP Module

Working with Net: SNMP

What’s Up?

Setting MIB-II Data

IP Router Mapping

Where to From Here?

Print Resources

Web Resources

6. Mobile Agents

What is a Mobile Agent?

Mobile-Agent Examples

Mobile-Agent Advantages/Disavantages

Perl Agents

The Agent.pm Module

Ooooh, Objects!

The Default Mobile Agent

A Launching Mobile-Agent Environment

A One-Shot Location

Relocating to Multiple Locations

The Mobile-Agent multiwho

The Mobile-Agent ipdetermine

The Cloning Mobile-Agent ipdetermine

Other Perl Agent Examples

Where to From Here?

Print Resources

Web Resources

Appendices

Index

About the author

Paul Barry is a lecturer in computing networking at the Institute of Technology in Carlow, Ireland where he regularly teaches undergraduate students and professionals how to program networks using Perl.