Scenario 1: One Vc, Multiple Protocols; Scenario 2: One Vc, One Protocol (Ip); Scenario 3: Multiple Vcs; Vpi And Vci - ZyXEL Communications P-660HW-T - V2 User Manual

because they cannot be automatically determined. What method(s) you use also depends on
how many VCs you have and how many different network protocols you need. The extra
overhead that ENET ENCAP encapsulation entails makes it a poor choice in a LAN-to-LAN
application. Here are some examples of more suitable combinations in such an application.

5.1.3.1 Scenario 1: One VC, Multiple Protocols

PPPoA (RFC-2364) encapsulation with VC-based multiplexing is the best combination
because no extra protocol identifying headers are needed. The PPP protocol already contains
this information.

5.1.3.2 Scenario 2: One VC, One Protocol (IP)

Selecting RFC-1483 encapsulation with VC-based multiplexing requires the least amount of
overhead (0 octets). However, if there is a potential need for multiple protocol support in the
future, it may be safer to select PPPoA encapsulation instead of RFC-1483, so you do not
need to reconfigure either computer later.

5.1.3.3 Scenario 3: Multiple VCs

If you have an equal number (or more) of VCs than the number of protocols, then select RFC-
1483 encapsulation and VC-based multiplexing.

5.1.4 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.

5.1.5 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.

5.1.5.1 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.

5.1.5.2 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.
Chapter 5 WAN Setup
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