Asus iPBX30 User manual

iPBX30
User Manual
E2883 / December 2006

Table of Contents
1 Introduction............................................................1
1.1 Features ....................................................................1
1.2 System Requirements ...............................................1
1.3 Using this Document .................................................2
1.3.1 Notational conventions............................................... 2
1.3.2 Typographical conventions......................................... 2
1.3.3 Special messages ...................................................... 2
2 Getting to Know your iPBX30...............................3
2.1 Parts List ...................................................................3
2.2 Hardware Features....................................................3
2.3 Software Features .....................................................4
2.3.1 NAT Features ............................................................. 4
2.3.2 Firewall Features........................................................ 5
2.3.2.1 Stateful Packet Inspection .................................. 5
2.3.2.2 Packet Filtering – ACL (Access Control List) ...... 5
2.3.2.3 Defense against DoS Attacks ............................. 6
2.3.2.4 Application Level Gateway (ALG) ....................... 7
2.3.2.5 Log...................................................................... 7
2.4 Finding Your Way Around..........................................8
2.4.1 Front Panel................................................................. 8
2.4.2 Rear Panel ................................................................. 9
2.4.3 Bottom View ............................................................. 10
2.5 Placement Options ..................................................10
2.5.1 Desktop Placement .................................................. 10
2.5.2 Wall Mount Instructions: ........................................... 10
3 Quick Start Guide ................................................12

3.1 Part 1 — Connecting the Hardware ........................12
3.1.1 Step 1. Connecting an ADSL or a cable modem...... 12
3.1.2 Step 2. Connecting computers or a Network............ 13
3.1.3 Step 3. Attaching the AC adapter ............................. 13
3.1.4 Step 4. Powering on iPBX30, the ADSL or cable
modem and power up your computers..................... 13
3.2 Part 2 — Conguring Your Computers ....................14
3.2.1 Before you begin ...................................................... 14
3.2.2 Windows® XP PC .................................................... 15
3.2.3 Windows® 2000 PC ................................................ 15
3.2.4 Windows® 95, 98, and ME PC................................. 16
3.2.5 Windows® NT 4.0 workstation: ................................ 17
3.2.6 Assigning static IP addresses to your PC................. 18
3.3 Part 3 — Quick Conguration of the iPBX30...........19
3.3.1 Setting Up the iPBX30.............................................. 19
3.3.2 Testing Your Setup ................................................... 21
3.3.3 Default Router Settings ............................................ 22
4 Using the Web UI Management..........................23
4.1 Log into the Web UI Management...........................23
4.2 Functional Layout ....................................................24
4.2.1 Menu Navigation ...................................................... 25
4.2.2 Commonly Used Buttons and Icons......................... 25
4.3 System Conguration Overview ...............................26
5 Router Setup........................................................27
5.1 LAN Conguration ...................................................27
5.1.1 LAN IP Address ........................................................ 27
5.1.2 LAN Conguration Parameters ................................ 27
5.1.3 Conguring the LAN IP Address............................... 28
5.2 WAN/DMZ Conguration .........................................29

5.2.1 WAN Connection Mode............................................ 29
5.2.2 PPPoE...................................................................... 30
5.2.2.1 WAN PPPoE Conguration Parameters........... 31
5.2.2.2 Conguring PPPoE for WAN ............................ 32
5.2.3 PPPoE Unnumbered................................................ 33
5.2.3.1 WAN PPPoE Unnumbered Conguration
Parameters....................................................... 34
5.2.3.2 Conguring PPPoE Unnumbered for WAN....... 35
5.2.4 Dynamic IP............................................................... 36
5.2.4.1 Conguring Dynamic IP for WAN...................... 36
5.2.5 Static IP.................................................................... 37
5.2.5.1 WAN or DMZ Static IP
Conguration Parameters .................................. 37
5.2.5.2 Conguring Static IP for WAN or DMZ.............. 38
5.2.6 PPTP........................................................................ 39
5.2.6.1 WAN PPTP Conguration Parameters ............. 39
5.2.6.2 Conguring PPTP for WAN............................... 41
5.3 WAN Load Balancing and Line Back Up..................41
5.3.1 WAN Load Balancing and Line Back Up Conguration
Parameters............................................................... 42
5.3.2 Setting Up WAN Load Balancing ............................ 43
5.3.3 Setting Up WAN Line Back Up................................. 44
6 DHCP Server Conguration................................45
6.1 DHCP (Dynamic Host Control Protocol)..................45
6.1.1 What is DHCP? ........................................................ 45
6.1.2 Why use DHCP? ...................................................... 45
6.1.3 Conguring DHCP Server ........................................ 46
6.1.4 Viewing Current DHCP Address Assignments ......... 48
6.1.5 Fixed DHCP Lease................................................... 48

6.1.5.1 Access Fixed DHCP Conguration Page –
(Advanced ->DHCP Server)............................. 48
6.1.5.2 Add a Fixed DHCP Lease................................. 49
6.1.5.3 Delete a Fixed DHCP Lease............................. 49
6.1.5.4 Viewing Fixed DHCP Lease Table.................... 49
6.2 DNS.........................................................................50
6.2.1 About DNS ............................................................... 50
6.2.2 Assigning DNS Addresses........................................ 50
6.2.3 Conguring DNS Relay ............................................ 51
7 Routing.................................................................52
7.1 Overview of IP Routes.............................................52
7.1.1 Do I need to dene static routes?............................. 52
7.2 Dynamic Routing using RIP (Routing Information
Protocol)..................................................................53
7.2.1 RIP Conguration Parameters ................................. 53
7.2.2 Conguring RIP........................................................ 54
7.3 Static Route.............................................................55
7.3.1 Static Route Conguration Parameters.................... 55
7.3.2 Adding Static Routes................................................ 56
7.3.3 Deleting Static Routes.............................................. 57
7.3.4 Viewing the Static Routing Table.............................. 57
8 Conguring DDNS...............................................58
8.1 DDNS Conguration Parameters ............................59
8.2 Conguring HTTP DDNS Client ..............................59
9 Conguring Firewall and NAT ............................61
9.1 Firewall Overview ....................................................61
9.1.1 Stateful Packet Inspection........................................ 61
9.1.2 DoS (Denial of Service) Protection........................... 62
9.1.3 Firewall and Access Control List (ACL).................... 62

9.1.3.1 Priority Order of ACL Rule ................................ 62
9.1.3.2 Tracking Connection State................................ 62
9.1.4 Default ACL Rules .................................................... 63
9.2 NAT Overview..........................................................63
9.2.1 NAPT (Network Address and Port Translation) or PAT
(Port Address Translation) ......................................... 64
9.2.2 Reverse NAPT / Virtual Server................................. 66
9.3 Firewall Settings – (Firewall/NAT ->Settings) ..........66
9.3.1 Firewall Options........................................................ 66
9.3.2 DoS Conguration.................................................... 67
9.3.2.1 DoS Protection Conguration Parameters........ 67
9.3.2.2 Conguring DoS Settings ................................. 69
9.4 ACL Rule Conguration Parameters .......................69
9.4.1 ACL Rule Conguration Parameters ........................ 69
9.5 Conguring ACL Rules – (Firewall ->ACL) ..............73
9.5.1 Add an ACL Rule ...................................................... 74
9.5.2 Modify an ACL Rule.................................................. 76
9.5.3 Delete an ACL Rule.................................................. 76
9.5.4 Display ACL Rules.................................................... 76
9.6 Conguring Self-Access ACL Rules –(Firewall/NAT
->Self-Access ACL) .................................................76
9.6.1 Add a Self-Access Rule............................................ 77
9.6.2 Modify a Self-Access Rule ....................................... 78
9.6.3 Delete a Self-Access Rule........................................ 78
9.6.4 View Congured Self-Access Rules......................... 79
9.7 Congure Virtual Server ..........................................79
9.7.1 Virtual Server Conguration Parameters.................. 79
9.7.2 Virtual Server Example 1 – Web Server................... 82
9.7.3 Virtual Server Example 2 – FTP Server ................... 84

9.7.4 Virtual Server Example 3 – FTP Server with Access
Control...................................................................... 84
9.8 Congure Special Application..................................86
9.8.1 Special Application Conguration Parameters ......... 86
9.8.2 Special Application Example .................................... 88
10 USB Application ................................................89
10.1 Congure USB Devices.........................................89
10.2 View the Status of Attached
USB Storage Devices............................................91
10.3 Congure FTP Service ..........................................91
11 System Management.........................................94
11.1 Congure System Services ...................................94
11.2 Login Password and System Settings ...................95
11.2.1 Changing Password ............................................... 95
11.2.2 Congure System Settings ..................................... 96
11.3 Viewing System Information ..................................96
11.4 Setup Date and Time.............................................97
11.4.1 View the System Date and Time ............................ 98
11.5 SNMP Setup ..........................................................99
11.5.1 SNMP Conguration Parameters ........................... 99
11.5.2 Conguring SNMP.................................................. 99
11.6 Log Setup .............................................................100
11.6.1 Setting Up Remote Logging
Using a Syslog Server............................................................100
11.6.2 View the System Log............................................ 101
11.7 System Conguration Management ....................101
11.7.1 Restore System Conguration to Factory Default
Settings ................................................................ 101
11.7.2 Backup System Conguration .............................. 103

11.7.3 Restore System Conguration.............................. 104
11.8 Firmware Upgrade ...............................................106
11.9 Restart System ....................................................108
11.10 Logout Web UI Management..............................109
12 SIP IP-PBX........................................................ 110
12.1 Conguration ....................................................... 111
12.1.1 General Setting .....................................................112
12.1.2 Gateway ................................................................114
12.1.3 Extensions.............................................................115
12.2 Dialing Plan .........................................................118
12.2.1 General..................................................................118
12.2.2 ITSP Server.......................................................... 120
12.2.3 Prex Routing....................................................... 121
12.3 Status ..................................................................122
12.3.1 Extensions Status................................................. 122
12.3.2 Channel Status..................................................... 123
12.3.3 ITSP Registry ....................................................... 123
12.4 Features ..............................................................124
12.4.1 Voicemail .............................................................. 124
12.4.2 Auto-provision (for AX-112) .................................. 128
12.5 Report..................................................................129
12.6 Utilities.................................................................129
12.6.1 Hot Reload ........................................................... 129
12.6.2 Service Restart..................................................... 130
12.7 Conguring Examples .........................................130
13 IP Addresses, Network Masks-
and Subnets......................................................134
13.1 IP Addresses .......................................................134

13.1.1 Structure of an IP address.................................... 134
13.2 Network classes ..................................................135
13.3 Subnet masks......................................................136
14 Troubleshooting ..............................................139
14.1 Diagnosing Problem using IP Utilities .................142
14.1.1 ping....................................................................... 142
14.1.2 nslookup............................................................... 143
15 Index .................................................................145
List of Figures
Figure 2.1 Front Panel LEDs.......................................................... 8
Figure 2.2 Rear Panel Connectors................................................. 9
Figure 3.1 Hardware Connections Overview................................ 13
Figure 3.2 Login Screen ............................................................... 20
Figure 3.3 System Status Page.................................................... 21
Figure 4.1 Login Screen ............................................................... 24
Figure 4.2 Typical Web UI Management Page............................. 25
Figure 4.3 System Status Page.................................................... 26
Figure 5.1 Network Setup Conguration – LAN Conguration..... 28
Figure 5.2 Network Setup Conguration Page – WAN Congura-
tion .............................................................................. 30
Figure 5.3 WAN – PPPoE Conguration ...................................... 30
Figure 5.4 WAN – PPPoE Unnumbered Conguration ................ 33
Figure 5.5 WAN – Dynamic IP (DHCP client) Conguration ........ 36
Figure 5.6 WAN – Static IP Conguration .................................... 37
Figure 5.7 WAN – PPTP Conguration ........................................ 40
Figure 5.8 Load Balancing Conguration ..................................... 43

Figure 6.1 DHCP Server Conguration Page............................... 46
Figure 6.2 DHCP Lease Table...................................................... 48
Figure 6.3 Fixed DHCP Lease Conguration Page...................... 49
Figure 7.1 RIP Conguration Page.............................................. 53
Figure 7.2 Static Route Conguration Page................................ 55
Figure 7.3 Static Route Conguration ......................................... 56
Figure 7.4 Sample Routing Table ................................................ 57
Figure 8.1 Network Diagram for HTTP DDNS.............................. 58
Figure 8.2 HTTP DDNS Conguration Page................................ 59
Figure 9.1 NAPT – Map Any Internal PCs to a Single Global IP
Address........................................................................ 65
Figure 9.2 Reverse NAPT – Relayed Incoming Packets to the
Internal Host Base on the Protocol, Port Number or
IP Address ................................................................... 65
Figure 9.3 Firewall General Conguration Page .......................... 69
Figure 9.4 ACL Conguration Page.............................................. 74
Figure 9.5 ACL Conguration Example ........................................ 75
Figure 9.6 Sample ACL List Table ................................................ 75
Figure 9.7 Self-Access ACL Conguration Page.......................... 77
Figure 9.8 Self-Access ACL Conguration Example .................... 78
Figure 9.9 Virtual Server Conguration Page............................... 79
Figure 9.10 Virtual Server Deployment Topology ......................... 82
Figure 9.11 Virtual Server Example 1 – Web Server.................... 83
Figure 9.12 Adding a New Service ............................................... 83
Figure 9.13 Virtual Server Example 2 – FTP Server .................... 84
Figure 9.14 Virtual Server Example 3 – FTP Server .................... 85
Figure 9.15 Firewall ACL for Virtual Server Example 3 – FTP
Server........................................................................ 86
Figure 9.16 Special Application Conguration Page .................... 88
Figure 10.1 Network Storage - FTP Server Setting...................... 90

Figure 10.2 Network Storage - FTP Server Conguration............ 92
Figure 11.1 System Services Conguration Page ........................ 94
Figure 11.2 System Administration Conguration Page ............... 95
Figure 11.3 System Information Page .......................................... 97
Figure 11.4 Time Zone Conguration Page.................................. 98
Figure 11.5 SNMP Conguration Page ...................................... 100
Figure 11.6 Syslog Server Conguration.................................... 100
Figure 11.7 Sample Log ............................................................. 101
Figure 11.8 Factory Reset Page................................................. 102
Figure 11.9 Factory Reset Conrmation..................................... 102
Figure 11.10 Factory Reset Count Down Timer ......................... 102
Figure 11.11 Backup System Conguration Page ...................... 103
Figure 11.12 Restore System Conguration Page ..................... 104
Figure 11.13 Selecting System Conguration from the File
Manager.................................................................. 105
Figure 11.14 System Conguration Restoration Conrmation ... 105
Figure 11.15 System Reboot Counter Timer .............................. 106
Figure 11.16 Firmware Upgrade Page ....................................... 106
Figure 11.17 Selecting Firmware from the File Manager............ 107
Figure 11.18 Firmware Upgrade Conrmation ........................... 107
Figure 11.19 Firmware Upgrade Progress ................................. 107
Figure 11.20 System Reboot Count Down Timer for Firmware
Upgrade................................................................. 108
Figure 11.21 Restart System Page............................................. 109
Figure 11.22 Web UI Management Logout Page ....................... 109
Figure 11.23 Conrmation for Closing Browser (IE) ................... 109
Figure 12.1 iPBX30 application ofce scenario...........................110
Figure 12.2 General setting page................................................112
Figure 12.3 Gateway page ..........................................................114
Figure 12.4 Extension page.........................................................115

Figure 12.5 General Dialing Plan page .......................................118
Figure 12.6 ITSP Server page.................................................... 120
Figure 12.7 Prex Routing page................................................. 121
Figure 12.8 Extension Status page ............................................ 123
Figure 12.9 ITSP Status page .................................................... 123
Figure 12.10 Voice mail page ..................................................... 125
Figure 12.11 Auto Provision page............................................... 129
Figure 12.12 Typical iPBX30 application set up ........................ 130
Figure 12.13 Extension List page.............................................. 131
Figure 12.14 Extension page..................................................... 131
Figure 12.15 SIP page................................................................ 132
Figure 14.1 Using the ping Utility................................................ 142
Figure 14.2 Using the nslookup Utility........................................ 143
List of Tables
Table 2.1 DoS Attacks .................................................................... 6
Table 2.2 Front Panel Label and LEDs........................................... 8
Table 2.3 Rear Panel Labels and LEDs.......................................... 9
Table 3.1 LED Indicators .............................................................. 14
Table 3.2 Default Settings Summary ............................................ 22
Table 4.1 Description of Commonly Used Buttons and Icons....... 25
Table 5.1 LAN Conguration Parameters..................................... 28
Table 5.2 WAN PPPoE Conguration Parameters ....................... 31
Table 5.3 WAN PPPoE Unnumbered Conguration Parameters . 34
Table 5.4 WAN Static IP Conguration Parameters ..................... 37
Table 5.5 WAN PPTP Conguration Parameters ......................... 39

Table 5.6 WAN Load Balancing and Line Back Up Conguration
Parameters................................................................... 42
Table 6.1 DHCP Conguration Parameters.................................. 47
Table 6.2 Fixed DHCP Lease Conguration Parameters ............. 49
Table 7.1 Static Route Conguration Parameters ........................ 53
Table 7.2 Static Route Conguration Parameters ........................ 55
Table 8.1 DDNS Conguration Parameters.................................. 59
Table 9.1 Firewall Options Parameters......................................... 66
Table 9.2 DoS Attack Denition .................................................... 67
Table 9.3 ACL Rule Conguration Parameters............................. 70
Table 9.4 Service Conguration Parameters................................ 72
Table 9.5 Virtual Server Conguration Parameters ...................... 80
Table 9.6 Port Numbers for Popular Applications......................... 81
Table 9.7 Special Application Conguration Parameters.............. 87
Table 9.8 Port Numbers for Popular Applications......................... 87
Table 10.1 Network Storage Conguration................................... 90
Table 10.2 FTP Sever Conguration ............................................ 92
Table 10.3 User Account Setting .................................................. 93
Table 11.1 SNMP Conguration Parameters................................ 99
Table 12.1 Conguration Parameters..........................................111
Table 13.1 IP Address Structure ................................................. 135
Table 14.1 Problems & suggested actions ................................. 139

1
iPBX30 User Manual Chapter 1
Chapter 1 Introduction
Congratulations on buying the ASUS iPBX30!
Your Local Area Network (LAN) will now be able to access the
Internet using your high-speed broadband connection such as
those with ADSL or cable modem. At the same time, you can have
a 30-user SIP-based IP PBX functionality.
This User Manual guides you in setting up the iPBX30, and
customizing its conguration to get the most out of this product.
1.1 Features
• LAN: 4-port Fast Ethernet switch
• WAN: Dual 10/100Base-T Ethernet ports to provide Internet
access for all computers on your LAN
• Firewall, and NAT (Network Address Translation) functions to
provide secure Internet access for your LAN
• Automatic network address assignment through DHCP Server
• Services including IP route, DNS and DDNS conguration
• User congurable dual-WAN or WAN plus DMZ support
• USB storage support
• SIP based IP-PBX support allowing up to30 SIP clients registration
• Support SIP trunking to ITSP and SIP gateway routing
• IP-PBX supports voice mail and email notication
• Voice codec support : G.711/G.729
• DTMF method support : In-band, RFC2833, Info
• Configuration program accessible via a web browser, such as
Microsoft Internet Explorer 6.0 or newer.
1.2 System Requirements
To use the iPBX30, you must have:
• ADSL or cable modem and the corresponding service up and
running, with at least one public Internet address assigned to

2
Chapter 1 iPBX30 User Manual
your WAN
• One or more computers each containing an Ethernet 10Base-T
or 100Base-T or 1000Base-T network interface card (NIC)
• (Optional) An Ethernet hub/switch, if you want to connect the
router to more than four computers on an Ethernet network.
• For system conguration using the web-based GUI: a web
browser such as Internet Explorer 6.0 or later.
1.3 Using this Document
1.3.1 Notational conventions
• Acronyms are dened the rst time they appear in the text.
Note: Provides clarification or information on the
current topic.
Denition: Explains terms or acronyms that may be
unfamiliar to many readers. These terms are also
included in the Glossary.
Warning: Provides messages of high importance,
including messages relating to personal safety or
system integrity.
• The iPBX30 is sometimes referred to as the “router”
or the ”gateway”.
• The terms LAN and network are used interchangeably to refer
to a group of Ethernet-connected computers at one site.
• Sequence of mouse actions is denoted by the “->” character.
For instance, System -> Network Setup means click the
System menu and then click the Network Setup submenu.
1.3.2 Typographical conventions
• Boldface type text is used for items you select from menus
and drop-down lists, and text strings you type when prompted
by the program.
1.3.3 Special messages
This document uses the following icons:

iPBX30 User Manual Chapter 2
3
Chapter 2 Getting to Know your iPBX30
2.1 Parts List
Your iPBX30 package include these items:
• iPBX30
• AC adapter
• Ethernet cable (“straight-through” type)
2.2 Hardware Features
Your iPBX30 contains these hardware features:
LAN
• 4-port Fast Ethernet switch
• Auto speed negotiation
WAN
• Dual 10/100M Ethernet ports
• Auto MDI/MDIX

Chapter 2 iPBX30 User Manual
4
2.3 Software Features
2.3.1 NAT Features
iPBX30 provides Network Address Translation (NAT) to share
a single high-speed Internet connection and to save the cost of
multiple connections required for the hosts on the LAN segments
connected to it. This feature conceals network address and
prevents them from becoming public. It maps unregistered IP
address of hosts connected to the LAN with valid ones for Internet
access. iPBX30 also provides reverse NAT capability, which
enables users to host various services such as e-mail servers, web
servers, etc. The NAT rules drive the translation mechanism. The
following types of NAT are supported by iPBX30.
• NAPT (Network Address and Port Translation)
Also called IP Masquerading or ENAT (Enhanced NAT). Maps
many internal hosts to only one globally valid IP address. The
mapping usually contains a pool of network ports to be used for
translation. Every packet is translated with the globally valid IP
address; the port number is translated with a free pool from the
pool of network ports.
• Reverse NAPT
Also called inbound mapping, port mapping,or virtual server.
Any packet coming to the router can be relayed to an internal
host based on the protocol, port number and/or IP Address
specied in the rule. This is useful when multiple services are
hosted on different internal hosts.

iPBX30 User Manual Chapter 2
5
2.3.2 Firewall Features
The firewall as implemented in iPBX30 provides the following
features to protect your network from being attacked and to prevent
your network from being used as the springboard for attacks.
• Stateful Packet Inspection
• Packet Filtering (ACL)
• Defense against Denial of Service Attacks
• Log
2.3.2.1 Stateful Packet Inspection
The iPBX30 Firewall uses “stateful packet inspection” that extracts
state-related information required for the security decision from the
packet and maintains this information for evaluating subsequent
connection attempts. It has awareness of application and creates
dynamic sessions that allow dynamic connections so that no ports
need to be opened other than the required ones. This provides
a solution which is highly secure and that offers scalability and
extensibility.
2.3.2.2 Packet Filtering – ACL (Access Control List)
ACL rule is one of the basic building blocks for network security.
Firewall monitors each individual packet, decodes the header
information of inbound and outbound traffic and then either
blocks the packet from passing or allows it to pass based on the
contents of the source address, destination address, source port,
destination port, and protocol defined in the ACL rules. ACL is a
very appropriate measure for providing isolation of one subnet from
another. It can be used as the rst line of defense in the network
to block inbound packets of specic types from ever reaching the
protected network.
The iPBX30 Firewall’s ACL methodology supports:
• Filtering based on destination and source IP address, port
number and protocol
• Use of the wild card for composing lter rules
• Filter Rule priorities

Chapter 2 iPBX30 User Manual
6
2.3.2.3 Defense against DoS Attacks
The iPBX30 Firewall has an Attack Defense Engine that protects
internal networks from known types of Internet attacks. It provides
automatic protection from Denial of Service (DoS) attacks such
as SYN flooding, IP smurfing, LAND, Ping of Death and all re-
assembly attacks. For example, the iPBX30 Firewall provides
protection from “WinNuke”, a widely used program to remotely
crash unprotected Windows systems in the Internet. The iPBX30
Firewall also provides protection from a variety of common Internet
attacks such as IP Spoofing, Ping of Death, Land Attack, and
Reassembly attacks.
The type of attack protections provided by the iPBX30 is listed in
the table below.
Table 2.1. DoS Attacks
Type of Attack Name of Attacks
Re-assembly Attacks Bonk, Boink, Teardrop ( New Tear),
Overdrop, Opentear, Syndrop, Jolt,
IP fragmentation overlap
ICMP Attacks Ping of Death, Smurf, Twinge
Flooders Logging only for ICMP Flooder, UDP
Flooder, SYN Flooder
Port Scans Logging only for TCP SYN Scan,
Attacking packets dropped: TCP
XMAS Scan, TCP Null Scan, TCP
Stealth Scan
Protection with PF Rules Echo-Chargen, Ascend Kill
Miscellaneous Attacks IP Spoong, LAND, Targa, Winnuke

iPBX30 User Manual Chapter 2
7
2.3.2.4 Application Level Gateway (ALG)
Applications such as FTP open connections dynamically based
on the respective application parameter. To go through the rewall
on the iPBX30, packets pertaining to an application, require a
corresponding allow rule. In the absence of such rules, the packets
will be dropped by the iPBX30 Firewall. As it is not feasible to
create policies for numerous applications dynamically (at the same
time without compromising security), intelligence in the form of
Application Level Gateways (ALG), is built to parse packets for
applications and open dynamic associations. The iPBX30 NAT
provides a number of ALGs for popular applications such as FTP,
and Netmeeting.
2.3.2.5 Log
Events in the network, that could be attempts to affect its security,
are recorded in the iPBX30 system log le.
The log maintains a minimum log details such as, time of packet
arrival, description of action taken by Firewall and reason for action.