ZyXEL p-662h-61 Guia Do Utilizador

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Chapter 3 Wizard Setup for Internet Access
3.1.1.4  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.
3.1.2  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.
3.1.2.1  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.
3.1.2.2  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.
3.1.3  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.
3.1.4  Internet Access Wizard Setup: First Screen
 In the SITE MAP screen click Wizard Setup to display the first wizard screen.