3Com Router User Manual

							Features of the 3Com Router Version 1.107
Network protocolIP service■Supports ARP
■Supports Static domain name resolution
■Supports IP Address Unnumbered
■Supports DHCP Server and DHCP relay
■Supports VLAN
■Supports IP Accounting
Non-IP service■Supports Novell IPX protocol, provide RIP and SAP to 
maintain the database of Internetwork routes and service 
information
■Supports DLSw of SNA system, implementing SNA through 
WAN transmission
IP performance■Supports IP fast forwarding
■Supports Van Jacobson TCP message header compression
IP routing ■Supports Static route management
■Supports Dynamic route protocol
■RIP-1/RIP-2
■OSPF
■BGP
■Supports IP routing policy 
■Supports IP policy-based routing
Multicast routing■Supports Internet Group Management Protocol (IGMP)
■Supports Multicast routing protocol
■PIM-DM
■PIM-SM
Attribute Description 
						

							8CHAPTER 1: 3COM ROUTER INTRODUCTION
Network securityAuthentication, 
Authorization and 
Accounting (AAA) 
service■Provides PPP and login user authentication
■Supports RADIUS, provides RADIUS 
authentication/accounting
■Provides local authentication 
■Supports CHAP and PAP authentication
Firewall■Supports standard access control list
■Supports extended access control list
■Supports interface-based access control list
■Supports time segment based access control list
NAT■Supports the users in LAN to access external networks by 
using the IP address in a configured address pool.
■Supports to configure relationship between access control 
list and address pool.
■Supports to configure relationship between access control 
list and interface.
■Supports the host of external network to access the internal 
server
■Supports to configure valid period for address translation
Data security■Supports terminal access security (user classification 
protection, user login authentication)
■Supports IPSec, provides tunnel and transmission 
encapsulation modes and supports AH and ESP security 
authentication
■Supports network data encryption card and provide IPSec 
encryption/decryption 
■Supports IKE, automatically negotiates on security key and 
create the security federation
Network reliabilityBackup center■Can back up any physical interface or sub-interface on the 
router and an X.25 or frame relay virtual circuit on the 
interface as well.
■Barring the Ethernet interface, any physical interfaces or 
virtual interface templates on the router can be used as 
backup interfaces. An X.25 or frame relay virtual circuit on 
the interface or a dialer route on the dial interface can be 
used as backup interface as well.
■Provides multiple backup interfaces for one main interface. 
These backup interfaces will be used according to their 
priorities.
■Backs up multiple main interfaces of the interfaces with 
multiple physical channels
■Supports to configure the conditions to switch the 
main/standby interfaces
Hot backup■Supports VRRP
Attribute Description 
						

							Features of the 3Com Router Version 1.109
Quality of service
(QoS)
Traffic classification 
and flow control■Supports CAR (Committed Access Speed) and packet 
priority, monitoring the network traffic entering ISP
■Supports LR (Line Rate of physical interface) to limit the total 
speed of packet transmission on physical interface
Traffic shaping■Uses buffer and token bucket to support general traffic 
shaping (GTS).
Congestion 
management■Supports FIFO (first-in-first-out queue)
■Supports PQ (priority queue)
■Supports CQ (customization queue)
■Supports WFQ (Weighted Fair queue)
Congestion 
Avoidance■Supports WRED (Weighted Random Early Detection), 
implementing flow-based congestion avoidance
Configuration 
management
Terminal server
Command line 
interface■Prompts provide information in English
■Prompt command line hierarchical protection, to ensure that 
the unauthorized users cannot access the router.
■Prompt Detailed debugging information, helpful for 
diagnosis of network faults
■Provides network test tools such as tracert and ping 
commands, to quickly diagnose whether the network is 
normal.
■Info-center loghost configuration
Terminal service■Performs local or remote configuration via the console port, 
asynchronous serial port, X.25 PAD, Telnet and Reverse 
Telnet etc.
■Logs on the UNIX host via Rlogin
■Configures router via the dumb terminal service
■Provides dumb terminal service via PRI port
■Supports the send function and provide the information 
interaction between terminal subscribers
■Terminal access via asynchronous serial port
■Supports dial-up POS and network POS accessing based on 
the shared POS access technology, which improves card 
account processing
System 
Management■Supports to upload and download programs/configuration 
files via FTP
■Supports to upload and download programs/configuration 
files via TFTP
■Supports on-line upgrade of the cards.
Network 
management■Supports SNMP (Simple Network Management Protocol)
■Supports RMON (Remote Monitor)
Attribute Description 
						

							10CHAPTER 1: 3COM ROUTER INTRODUCTION
New Features of the 
3Com Router 1.xNew features have been added to the 3Com Router1.10.
Support New InterfacesE3 and CE3 Interfaces
Both E3 and E1 are part of the ITU-T digital carrier architecture and are used in 
most regions beyond North America. The data transmission speed of E3 is 
34.368
 Mbps and the line code is HDB3. E3/CE3 interfaces support the link layer 
protocols including PPP, HDLC, Frame Relay, LAPB, and X.25, as well as the 
network protocol such as IP. Similar to E1/CE1, E3/CE3 interfaces can work in two 
operating modes, namely, E3 mode and CE3 mode.
■When working in E3 mode, an E3/CE3 interface is a timeslot-less interface of 
the bandwidth of 34.368 Mbps.
■When working in CE3 mode, it can multiplex/demultiplex 16 channels of E1 
signals. The E3-to-E1 multiplexing is compliant with the G.751 and G.742 
provisions of ITU-T. In addition, each E1 interface can be divided into 32 
timeslots.
E1-F/T1-F Interface
E1-F and T1-F interfaces refer to the fractional E1 and T1 interfaces, which are 
equivalent to the simplified CE1/PRI and CT1/PRI interfaces. In essence, they are a 
low-cost approach to E1/T1 access. In a simple E1 or T1 access application 
requiring neither division of multiple channel groups nor ISDN PRI, either the E1-F 
or T1/F interface will be a good choice.
Null Interface
The functions of the Null interface are similar to those of null devices supported by 
many operating systems. It is always in UP status, but cannot forward data packets 
or configure IP addresses or encapsulate other protocols. Null interface is a virtual 
interface with software characteristics. Any network data packet sent to this 
interface will be dropped.
FRoIP and FRoISDNFrame Relay over IP
As IP networks have gained wider acceptance, Frame Relay (FR) applications have 
relied on IP networks for data communication and interconnection between 
networks. FRoIP technology enables IP networks to carry FR data by establishing a 
GRE tunnel across the IP network to connect the two FR networks at both ends of 
the IP network.
Frame Relay over ISDN
Frame Relay over ISDN provides a method for accessing the Frame Relay network 
based on ISDNs and the related devices. This shortens the time for users to access 
and lowers the cost of leased lines.
The Frame Relay over ISDN is mainly used in the following two aspects:
■The simplest application is to take Frame Relay over ISDN as the main 
communications method. That is, all the routers support Frame Relay over 
ISDN, and the individual routers can directly access the Frame Relay networks 
(without TA adapters) to communicate. 
						

							New Features of the 3Com Router 1.x11
■Combined with BDR, Frame Relay over ISDN can be taken as the backup 
communication method for Frame Relay.
Multilink Frame RelayThe Multilink Frame Relay (MFR) feature introduces functionality based on the 
Frame Relay Forum Multilink Frame Relay UNI/NNI Implementation Agreement 
(FRF.16). This feature provides a cost-effective way to increase bandwidth for 
particular applications by enabling multiple serial links to be aggregated into a 
single bundle of bandwidth. MFR is supported on User-to-Network Interfaces (UNI) 
and Network-to-Network Interfaces (NNI) in Frame Relay networks.
FR CompressionFR compression technology is used to compress the FR packets for the purpose of 
effectively saving the network bandwidth and decreasing the network load, and 
hence to implement data transmission over FR networks with high efficiency. 
3Com Routers follow the FRF.9 standard for FR compression. FR compression can 
achieve a significant effect on a FR line with low bandwidth. FR interfaces fall into 
two categories, namely, point-to-point interface and multipoint interface.
BridgeBridges are a type of network devices that connect LANs at the data link layer for 
data transmission among them. For some small or remote networks, a bridge can 
reduce the network maintenance cost and free the network terminal subscribers 
from making special settings for the devices. In addition, its network connection is 
no difference from a HUB.
3Com Routers support transparent bridging and are compatible with IEEE 802.1d. 
The routers support the STP and bridging functions defined in IEEE 802.1d and 
support bridging on the links encapsulated with PPP, HDLC, X.25, or Frame Relay, 
as well as bridging on VLAN sub-interfaces and BDR. Furthermore, the routers can 
implement multi-port binding and load sharing.
IP CountIP count implements accounting on the incoming and outgoing packets as well as 
the packets denied by the firewall on the routers. When implementing IP count, 
whether the packets match the count list rules and whether the packets are 
denied by the firewall, are two standards by which the router sorts the 
bidirectional packets for count. When making data statistics, both the number of 
packets and the total bytes are recorded. 
Virtual Router 
Redundancy Protocol 
(VRRP)Virtual Router Redundancy Protocol (VRRP) is a fault tolerant protocol. Normally, 
the default route set for a host in a network takes the GW route of the network as 
the next hop. Through the default route, the host can carry out the 
communications with the external networks. If the GW route fails to work, all the 
hosts that take it as the next hop on the segment will be unable to communicate 
with the outside. VRRP can fulfill the router redundancy by assigning multiple 
routers into a router group. Thus, whenever a member fails to work, a backup 
router will take up the work of the failed router and thus can ensure the normal 
communications between the hosts on the network and the outside. 
						

							12CHAPTER 1: 3COM ROUTER INTRODUCTION 
						

							2
3COM ROUTER USER INTERFACE
This chapter includes information on the following topics:
■Establish Configuration Environment
■Command Line Interface (CLI)
■User Identity Management
■Basic Configuration and Management of the System
Establish 
Configuration 
EnvironmentThe 3Com Router 1.x supports local and remote configuration, and the 
configuration environment can be established in the following ways:
Local Configuration 
Environment via Console 
PortThe local configuration environment can be established via the console port 
(configuration interface).
1As shown in Figure 2, the local configuration environment can be established via 
the console port just by connecting the serial port of the computer with the 
console port of the router via a standard RS-232 cable.
Figure 2   Establish a local configuration environment via configuration interface
On 3Com modular routers the CONSOLE port and AUX port are on the front of 
the unit, while other ports are on the rear of the unit. The above diagram shows 
the rear of the unit. For details, please refer to the 3Com Installation Guide.
2Run a terminal emulator application such as HyperTerminal of Win9X on the 
computer to establish a new connection. Select an RS-232 serial port on the 
computer, set the terminal communication baudrate parameters as 9600 bps, 8 
data bits, 1 stop bit, no parity and no flow control, and select the terminal 
emulation type as VT100, as shown in the following diagram (“HyperTerminal” 
setting interface in Windows 9X).
portCable
Console interface
(Configuration
RS-232 serialConfiguration interface (Console)
interface)
RouterWorkstation portCable
Console interface
(Configuration
RS-232 serialConfiguration interface (Console)
interface)
Workstation
RS-232 serialConfiguration interface (Console)
interface)
Workstation RS-232 serialConfiguration interface (Console)
interface)Workstation 
						

							14CHAPTER 2: 3COM ROUTER USER INTERFACE
Figure 3   Establish a new connection
Figure 4   Select the computer serial port for actual connection
  
						

							Establish Configuration Environment15
Figure 5   Set port communication parameters 
Figure 6   Select terminal emulation type 
3Power on the router to display the self-test information of the router. Press Enter 
after the self-test to display the prompt “Username:” and “password:”. Type in 
the correct username and the password, then enter the system view of Router.
  
						

							16CHAPTER 2: 3COM ROUTER USER INTERFACE
4Enter the command to configure the router or view the running status of the 
router. Enter “?” to get help when necessary. For details of specific commands, 
please refer to the following chapters.
Remote Configuration 
Environment via Async 
Serial PortThe router powers on, then creates a remote configuration environment by 
connecting to the asynchronous serial ports of the router (including 
synchronous/asynchronous serial port, AUX interface, i.e., auxiliary interface, etc.) 
via modem dial-up. Detailed below is the description on how to establish a remote 
configuration environment via asynchronous serial port, with AUX interface as an 
example.
To establish a remote configuration environment via an asynchronous serial port of 
the router, pre-configure it to flow mode. For specific setting method, please refer 
to the Terminal Service chapter in this manual. 
The modem connected to the asynchronous serial interface should be set to 
auto-answer mode.
1As shown in Figure 7, connect a modem to computer serial port and another 
modem to the routers asynchronous serial port (AUX interface in the diagram). 
Figure 7   Establish a remote configuration environment
2Run a terminal emulator application, such as HyperTerminal of Win9X, on the 
computer to establish a new connection. Select the RS-232 serial port on the 
computer for actual connection; set the terminal communication parameters to 
9600 baud rate, 8 data bits, 1 stop bit, no parity, no flow control or hardware flow 
control, and select the terminal emulation type as VT100, the same as the 
connection established via the console port.
3Before powering on the router, power on its external modem. Initialize the router 
via AT command, and then dial on the remote computer to establish a connection 
with the router, as shown in the following figure.
Tel N o. 660000
Modem
M odem
Workstation
AUX interface
PSTN
RouterRS -232
S erial port