Technical Reference; Encapsulation - ZyXEL Communications P-660HN-51 User Manual

5.3 Technical Reference

This section provides some technical background information about the topics covered in this chapter.

5.3.1 Encapsulation

Be sure to use the encapsulation method required by your ISP. The Zyxel Device supports the following
methods.
5.3.1.1 PPP over Ethernet
The Zyxel Device supports PPPoE (Point-to-Point Protocol over Ethernet). PPPoE is an IETF Draft standard
(RFC 2516) specifying how a personal computer (PC) interacts with a broadband modem (DSL, cable,
wireless, etc.) connection. The PPPoE option is for a dial-up connection using PPPoE.
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.
5.3.1.2 PPPoA
PPPoA stands for Point to Point Protocol over ATM Adaptation Layer 5 (AAL5). A PPPoA connection
functions like a dial-up Internet connection. The Zyxel Device encapsulates the PPP session based on
RFC1483 and sends it through an ATM PVC (Permanent Virtual Circuit) to the Internet Service Provider's
(ISP) DSLAM (Digital Subscriber Line (DSL) Access Multiplexer). Please refer to RFC 2364 for more
information on PPPoA. Refer to RFC 1661 for more information on PPP.
Chapter 5 Broadband
P-660HN-51 User's Guide
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