ZyXEL Communications P-660R-F1 series, Руководство пользователя

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Chapter 4 WAN Setup
P-660R-F1 Series User’s Guide
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4.1.3.2 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.
4.1.3.3 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.
4.1.4 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.
4.1.5 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.
4.1.5.1 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.
4.1.5.2 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.
4.1.5.3 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.
4.1.6 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.