Encapsulation & Multiplexing Scenarios - ZyXEL Communications Prestige 642 User Manual

Prestige 642 ADSL Internet Access Router
When Menu 11.1 - Remote Node Profile appears fill in the fields as described in the table that follows to
define this remote profile. The Remote Node Profile Menu Fields table shows how to configure the Remote
Node Menu.
4.1.2 Encapsulation & Multiplexing Scenarios
For Internet Access you should use the encapsulation and multiplexing methods used by your ISP. For a
LAN-to-LAN application, e.g., branch office and corporate headquarters, prior mutual agreement on
methods used is necessary because there is no mechanism to automatically determine
encapsulation/multiplexing. Selection of which encapsulation and multiplexing methods to use depends on
how many VCs you have and how many different network protocols you need. The extra overhead that
ENET ENCAP encapsulation entail makes it a poor choice in a LAN-to-LAN application. Here are some
examples of more suitable combinations in such an application.
Scene 1. One VC, Multiple Protocols
PPP (RFC 2364) encapsulation with VC-based multiplexing is the best combination because the extra
protocol identifying headers that LLC-based multiplexing uses is unneeded. The PPP protocol already
contains this information.
Scene 2. One VC, One Protocol (IP)
Select 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 PPP encapsulation instead of RFC-1483, so you don't need to reconfigure either machine when the
time comes.
Scene 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.
Remote Node Configuration
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