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access control and billing functionality in a manner similar to dial-up services using PPP. The

BIPAC-5100/5100W encapsulates the PPP session based on RFC1483 and sends it through

an ATM PVC (Permanent Virtual Circuit) to the Internet Service Provider's (ISP) DSLAM

(digital access multiplexer). Please refer to RFC 2364 for more information on PPPoA. Refer to

RFC 1661 for more information on PPP.

3.2.4 RFC 1483

RFC 1483 describes two methods for Multiprotocol Encapsulation over ATM Adaptation Layer

5 (AAL5). The first method allows multiplexing of multiple protocols over a single ATM virtual

circuit (LLC-based multiplexing) and the second method assumes that each protocol is carried

over a separate ATM virtual circuit (VC-based multiplexing). Please refer to the RFC for more

detailed information.

3.3 Multiplexing

There are two conventions to identify what protocols the virtual circuit (VC) is carrying. Be sure

to use the multiplexing method required by your ISP.

3.3.1 VC-based Multiplexing

In this case, by prior mutual agreement, each protocol is assigned to a specific virtual circuit;

for example, VC1 carries IP, etc. VC-based multiplexing may be dominant in environments

where dynamic creation of large numbers of ATM VCs is fast and economical.

3.3.2 LLC-based Multiplexing

In this case one VC carries multiple protocols with protocol identifying information being

contained in each packet header. Despite the extra bandwidth and processing overhead, this

method may be advantageous if it is not practical to have a separate VC for each carried

protocol, for example, if charging heavily depends on the number of simultaneous VCs.

3.4 VPI and VCI

Be sure to use the correct Virtual Path Identifier (VPI) and Virtual Channel Identifier (VCI)

numbers assigned to you. The valid range for the VPI is 0 to 255 and for the VCI is 32 to 65535

(0 to 31 is reserved for local management of ATM traffic). Please see the appendix for more

information.

3.5 Wizard Setup Configuration: First Screen

In the SITE MAP screen click Wizard Setup to display the first wizard screen.

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The following table describes the labels in this screen.

LABEL

DESCRIPTION

Mode

From the

Mode

drop-down list box, select

Routing

(default) if your ISP allows

multiple computers to share an Internet account. Otherwise select

Bridge

.

Encapsulation

Select the encapsulation type your ISP uses from the

Encapsulation

drop-down

list box. Choices vary depending on what you select in the

Mode

field.

If you select

Bridge

in the

Mode

field, select either

PPPoA

or

RFC 1483

.

If you select

Routing

in the

Mode

field, select

PPPoA

,

RFC 1483

,

ENET ENCAP

or

PPPoE

.

Multiplex

Select the multiplexing method used by your ISP from the

Multiplex

drop-down

list box either VC-based or LLC-based.

Virtual Circuit ID

VPI (Virtual Path Identifier) and VCI (Virtual Channel Identifier) define a virtual

circuit. Refer to

VPI

Enter the VPI assigned to you. This field may already be configured.

VCI

Enter the VCI assigned to you. This field may already be configured.

Next

Click this button to go to the next wizard screen. The next wizard screen you see

depends on what protocol you chose above. Click on the protocol link to see the

next wizard screen for that protocol.

3.6 IP Address and Subnet Mask

Similar to the way houses on a street share a common street name, so too do computers on a

LAN share one common network number.

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Where you obtain your network number depends on your particular situation. If the ISP or your

network administrator assigns you a block of registered IP addresses, follow their instructions

in selecting the IP addresses and the subnet mask.

If the ISP did not explicitly give you an IP network number, then most likely you have a single

user account and the ISP will assign you a dynamic IP address when the connection is

established. If this is the case, it is recommended that you select a network number from

192.168.0.0 to 192.168.255.0 and you must enable the Network Address Translation (NAT)

feature of the BIPAC-5100/5100W. The Internet Assigned Number Authority (IANA) reserved

this block of addresses specifically for private use; please do not use any other number unless

you are told otherwise. Let's say you select 192.168.1.0 as the network number; which covers

254 individual addresses, from 192.168.1.1 to 192.168.1.254 (zero and 255 are reserved). In

other words, the first three numbers specify the network number while the last number

identifies an individual computer on that network.

Once you have decided on the network number, pick an IP address that is easy to remember,

for instance, 192.168.1.254, for your BIPAC-5100/5100W, but make sure that no other device

on your network is using

that IP address.

The subnet mask specifies the network number portion of an IP address. Your

BIPAC-5100/5100W will compute the subnet mask automatically based on the IP address that

you entered. You don't need to change the subnet mask computed by the BIPAC-5100/5100W

unless you are instructed to do otherwise.

3.7 IP Address Assignment

A static IP is a fixed IP that your ISP gives you. A dynamic IP is not fixed; the ISP assigns you a

different one each time. The Single User Account feature can be enabled or disabled if you

have either a dynamic or static IP. However the encapsulation method assigned influences

your choices for IP address and ENET ENCAP Gateway.

3.7.1 IP Assignment with PPPoA or PPPoE Encapsulation

If you have a dynamic IP, then the IP Address and ENET ENCAP Gateway fields are not

applicable (N/A). If you have a static IP, then you only need to fill in the IP Address field and not

the ENET ENCAP Gateway field.

3.7.2 IP Assignment with RFC 1483 Encapsulation

In this case the IP Address Assignment must be static with the same requirements for the IP

Address and ENET ENCAP Gateway fields as stated above.

3.7.3 IP Assignment with ENET ENCAP Encapsulation

In this case you can have either a static or dynamic IP. For a static IP you must fill in all the IP

Address and ENET ENCAP Gateway fields as supplied by your ISP. However for a dynamic IP,

the BIPAC-5100/5100W acts as a DHCP client on the WAN port and so the IP Address and

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ENET ENCAP Gateway fields are not applicable (N/A) as the DHCP server assigns them to

the BIPAC-5100/5100W.

3.7.4 Private IP Addresses

Every machine on the Internet must have a unique address. If your networks are isolated from

the Internet, for example, only between your two branch offices, you can assign any IP

addresses to the hosts without problems. However, the Internet Assigned Numbers Authority

(IANA) has reserved the following three blocks of IP addresses specifically for private

networks:

10.0.0.0 - 10.255.255.255

172.16.0.0 - 172.31.255.255

192.168.0.0 - 192.168.255.255

You can obtain your IP address from the IANA, from an ISP or it can be assigned from a

private network. If you belong to a small organization and your Internet access is through an

ISP, the ISP can provide you with the Internet addresses for your local networks. On the other

hand, if you are part of a much larger organization, you should consult your network

administrator for the appropriate IP addresses.

3.8 Nailed-Up Connection (PPP)

A nailed-up connection is a dial-up line where the connection is always up regardless of traffic

demand. The BIPAC-5100/5100W does two things when you specify a nailed-up connection.

The first is that idle timeout is disabled. The second is that the BIPAC-5100/5100W will try to

bring up the connection when turned on and whenever the connection is down. A nailed-up

connection can be very expensive for obvious reasons.

Do not specify a nailed-up connection unless your telephone company offers flat-rate service

or you need a constant connection and the cost is of no concern

3.9 NAT

NAT (Network Address Translation - NAT, RFC 1631) is the translation of the IP address of a

host in a packet, for example, the source address of an outgoing packet, used within one

network to a different IP address known within another network.

3.10 Wizard Setup Configuration: Second Screen

The second wizard screen varies depending on what mode and encapsulation type you use.

All screens shown are with routing mode. Configure the fields and click Next to continue.

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3.10.1 PPPoE

Select PPPoE from the Encapsulation drop-down list box in the first wizard screen to display

the screen as shown.

The following table describes the labels in this screen.

LABEL

DESCRIPTION

Service Name

Type the name of your PPPoE service here.

User Name

Configure

User Name

and

Password

fields for

PPPoA

and

PPPoE

encapsulation

only. Enter the user name exactly as your ISP assigned. If assigned a name in the

form

user@domain

where domain identifies a service name, then enter both

components exactly as given.

Password

Enter the password associated with the user name above.

IP Address

A static IP address is a fixed IP that your ISP gives you. A dynamic IP address is not

fixed; the ISP assigns you a different one each time you connect to the Internet. The

Single User

Account feature can be used with either a dynamic or static IP address.

Select

Obtain an IP Address Automatically

if you have a dynamic IP address;

otherwise select

Static IP Address

and type your ISP assigned IP address in the

IP

Address

text box below.

Connection

Select

Connect on Demand

when you don't want the connection up all the time and

specify an idle time-out (in seconds) in the

Max. Idle Timeout

field. The default

setting selects

Connection on Demand

with 0 as the idle time-out, which means

the Internet session will Select

Nailed-Up Connection

when you want your

connection up all the time. The BIPAC-5100/5100W will try to bring up the

connection automatically if it is disconnected.