Installation manual

G.dmt = G.992.1, derived from T1.413; also known as ‘Full rate’
This is the type of ADSL most commonly implemented now.
IP over LLC/SNAP
This is a routed connection method and is one of the options of RFC 1483.
Note that ‘RFC 1483’ by itself doesn’t tell you what the protocol is - you need to know if the
connection is bridged or routed to know what ‘RFC 1483’ means.
Micro-filter
A filter designed to be connected between the ADSL line and every phone that is connected to
the line.
PPP
The protocol used to carry TCP/IP traffic to the ISP across modem and ISDN links.
PPP incorporates authentication (username/password checking).
Because of its historical use for modem and ISDN users, ISPs favour the use of PPP as an
encapsulating protocol for ADSL users.
PPP over ATM - RFC 2364
PPP over ATM (PPPoATM) is the most elegant and simple implementation that provides PPP
encapsulation over a routed ADSL connection.
Microsoft provides a PPP over ATM stack in Windows 98SE, Windows Me and Windows 2000
and this provides an almost ideal implementation for ‘passive’ ADSL modems such as internal
cards and USB devices.
PPP over Ethernet
PPP over Ethernet (PPPoE) is used in some existing ADSL services. It is a less than elegant
solution since it requires a custom ‘driver’ in the user’s PC. This driver works in a similar manner
to Dial-Up Networking, but Microsoft have not implemented it so 3rd-party software is required.
So, even if you’re using an intelligent (as opposed to ‘passive’) device, you’re dependent on the
PPP over Ethernet (PPPoE) client being available for your operating system platform.
RFC 1483
This RFC includes 4 options, only two of which are relevant to ADSL:
* IP over LLC/SNAP is a routed connection method, sometimes referred to as “RFC1483R”
* Ethernet over LLC/SNAP is a bridged connection method, sometimes referred to as
“RFC1483B”
Note that ‘RFC 1483’ by itself doesn’t tell you what the protocol is - you need to know if the
connection is bridged or routed to know what ‘RFC 1483’ means.
RFC 2516
‘Informational’ RFC describing PPP over Ethernet.
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CopperJet 81x
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