ZyXEL Communications P-660HW-DX, User Manual

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Chapter 5 WAN Setup
P-660HW-Dx User’s Guide
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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.
5.1.5.3 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 ZyXEL Device acts as a DHCP client on the WAN port and so the IP
Address and ENET ENCAP Gateway fields are not applicable (N/A) as the DHCP server
assigns them to the ZyXEL Device.
5.1.6 Nailed-Up Connection (PPP)
A nailed-up connection is a dial-up line where the connection is always up regardless of traffic
demand. The ZyXEL Device does two things when you specify a nailed-up connection. The
first is that idle timeout is disabled. The second is that the ZyXEL Device 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.