Technical Reference - ZyXEL Communications P-870H Series User Manual

5.6 Technical Reference

The following section contains additional technical information about the ZyXEL
Device features described in this chapter.
Encapsulation
Be sure to use the encapsulation method required by your ISP. The ZyXEL Device
can work in bridge mode or routing mode. When the ZyXEL Device is in routing
mode, it supports the following methods.
ENET ENCAP
The MAC Encapsulated Routing Link Protocol (ENET ENCAP) is only implemented
with the IP network protocol. IP packets are routed between the Ethernet interface
and the WAN interface and then formatted so that they can be understood in a
bridged environment. For instance, it encapsulates routed Ethernet frames into
bridged ATM cells.
PPP over Ethernet
Point-to-Point Protocol over Ethernet (PPPoE) provides access control and billing
functionality in a manner similar to dial-up services using PPP. PPPoE is an IETF
standard (RFC 2516) specifying how a personal computer (PC) interacts with a
broadband modem (DSL, cable, wireless, etc.) connection.
For the service provider, PPPoE offers an access and authentication method that
works with existing access control systems (for example RADIUS).
One of the benefits of PPPoE is the ability to let you access one of multiple network
services, a function known as dynamic service selection. This enables the service
provider to easily create and offer new IP services for individuals.
Operationally, PPPoE saves significant effort for both you and the ISP or carrier, as
it requires no specific configuration of the broadband modem at the customer site.
By implementing PPPoE directly on the ZyXEL Device (rather than individual
computers), the computers on the LAN do not need PPPoE software installed,
since the ZyXEL Device does that part of the task. Furthermore, with NAT, all of
the LANs' computers will have access.
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
P-870H/HW Series User's Guide
Chapter 5 WAN Setup
71