INTERNET-DRAFT "Network Working Group" G. Chanteau
Y. Codaccioni
V. Faineant
Document: draft-ietf-udlr-pppoe-00.txt France Telecom
Expires: April 2002 November 2001
Using PPPoE with LLTM Mechanism
<draft-ietf-udlr-pppoe-00.txt>
Status of this Memo
This document is an Internet-Draft and is in full conformance
with all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
Abstract
This memo describes the use and the configuration of the PPPoE over a
UniDirectionnal Link such as satellite network. This document explains
the advantages of the PPPoE and LLTM in such architecture.
Table of Contents
Status of this Memo .............................................. 1
Abstract ......................................................... 1
1. Introduction ................................................... 2
2. Network architecture ........................................... 2
2.1 Equipments description ......................................... 3
2.2 Connections description ........................................ 3
2.3 Multicast....................................................... 3
3. Advantages ..................................................... 4
4. Evolutions .................................................... 5
4.1 Multi-receiver connectivity .................................... 5
5. References .................................................... 6
6. Author's Addresses ............................................ 6
7. Full copyright statement ...................................... 7
Chanteau & Codaccioni & Faineant [Page 1]
INTERNET-DRAFT Using PPPoE with LLTM November 2001
1. Introduction
The initial idea was to create a real satellite local loop where a
satellite broadband Internet access can replace a terrestrial one
in areas that are non covered by terrestrial high speed Internet
access such as ADSL. This architecture remains open and in order
to provide the same type of services than in ADSL networks, an
interconnection with a Broadband Access Server (BAS) is needed.
This interconnection uses the PPPoE (PPP over Ethernet).
This document explains the advantages of the PPPoE and LLTM [RFC 3077]
in such a satellite Local Loop : compatibility with all IP world and
performances equivalent to ADSL. It also shows the possible
evolutions of this architecture.
2. Network architecture
Unidirectional Link
-------------<-----------
| |
| |
| |
| |
| |
\|/ .
. /|\
| |
--------- --------- --------
Ethernet | PPPoE/| IP Networks | LLTM | PPPoE | BAS |
-------| LLTM |-------->------|Server |---------| |
| Router| | | | |
| --------- --------- --------
| ____ |
|--|PC| |
| ---- --------
| ____ LAN | ISP |
|--|PC| --------
| ----
Figure 1 : Connectivity to a BAS via PPPoE/LLTM
In the Figure 1, the Connections without any arrow are
bidirectionnal.
Chanteau & Codaccioni & Faineant [Page 2]
INTERNET-DRAFT Using PPPoE with LLTM November 2001
2.1. Equipments description
Here are the description of the main equipments of this
architecture :
- the end user is a PC on a LAN.
It integrates an Ethernet card.
- the satellite terminal is a router with an LLTM client
(implementing the RFC 3077).
It integrates one satellite reception card, one Ethernet card
and one bidirectional interface connected to the Internet.
Firstly, it transports the traffic from the end users to
the Internet via the return channel which can be either
satellite or terrestrial.
Secondly, it receives traffic from the DVB channel
(previously coming from the Internet) via its DVB interface
and deliver it to the end users.
- the LLTM server (implementing the RFC 3077) is acting as
an Ethernet bridge.
This is the endpoint of the GRE tunnel where traffic is
encapsulated and decapsulated. The LLTM server is
directly connected to a BAS.
- the BAS (Broadband Access Server) manages the PPPoE connection.
The PPPoE can end into the BAS (open model) or continue and end into
the RADIUS server of an ISP (closed model). The PPPoE authentication
is done where the PPPoE tunnel ends.
2.2 Connections description (Unicast)
Here are the different steps of a connection to Internet :
- when an end user tries to go on the Internet, the satellite
terminal implements the LLTM : it initiates first a GRE tunnel
between its DVB interface and the LLTM server. Now a LAN has
been emulated and all the Ethernet frames can be directed to
the LLTM server and therefore to the BAS.
Chanteau & Codaccioni & Faineant [Page 3]
INTERNET-DRAFT Using PPPoE with LLTM November 2001
- the satellite terminal exchanges pieces of information with
the BAS (initiation session) in order to initiate the PPPoE
session.
- In case of cloded model the BAS redirect the PPP connection
to the right ISP through a L2TP tunnel.
- the end user can connect to a distant server of the Internet.
2.3 Multicast
It is important to notice that PPPoE supports only PPP connection for
Unicast flows. The multicast is provided directly by the ASP using IP
over LLTM. In this configuration, the ASP can offer n to m multicast
services.
There is also possibility to offer the Mbone connectity through the BAS
without using PPPoE.
3. Advantages
The Local Satellite Loop architecture offers the following advantages :
- a return channel flexibility : the use of LLTM allows to
define an access network wether with a satellite return channel
or with a terrestrial return channel. Besides a standby
terrestrial link can be used automatically in case of failure
of the satellite return channel.
- a multi-ISP configuration for the Internet access.
- a difference is made between the ASP and the ISP
- complementarity with the ADSL network :
* performances : more than 128 kbps for the return channel
and up to 40 Mbps for a gateway throughput
* client segmentation : corporate or residential
* interconnection with the terrestrial network
* reduction of the access costs
* re-use of the ADSL management system (accounting,
billing, etc.)
- interactif Multicast support (m to m)
Chanteau & Codaccioni & Faineant [Page 4]
INTERNET-DRAFT Using PPPoE with LLTM November 2001
4. Conclusion
The Local Satellite Loopb architecture has been already validated in laboratory.
A real experimentation will begin on the fourth quarter of 2001 with a few tens
of satellite terminals. Different evolutions are studied on multicast and security
aspects.
5. References
[UDLR] E. Duros, W. Dabbous, H. Izumiyama, N. Fujii, Y. Zhang, "A
Link-Layer Tunneling Mechanism for Unidirectional Links", RFC 3077,
March 2001
[PPPoE] L. Mamakos, K. Lidl, J. Evarts, D. Carrel, D. Simone, R.
Wheeler, "A Method for Transmitting PPP Over Ethernet (PPPoE)",
RFC 2516, February 1999
[GRE] D. Farinacci, T. Li, S. Hanks, D. Meyer, P. Traina, "Generic
Routing Encapsulation (GRE)", RFC 2784, March 2000
6. Author's Addresses
Gilles Chanteau
France Telecom R&D
38/40 rue du Gnral Leclerc
92131 Issy-Les-Moulineaux Cedex
France
Phone: (+33) 1 45 29 58 67
EMail : gilles.chanteau@rd.francetelecom.com
Yann Codaccioni
France Telecom R&D
38/40 rue du Gnral Leclerc
92131 Issy-Les-Moulineaux Cedex
France
Phone: (+33) 1 45 29 64 67
EMail : yann.codaccioni@rd.francetelecom.com
Virginie Fainant
France Telecom R&D
38/40 rue du Gnral Leclerc
92131 Issy-Les-Moulineaux Cedex
France
Phone: (+33) 1 45 29
EMail : virginie.faineant@rd.francetelecom.com
Chanteau & Codaccioni & Faineant [Page 5]
INTERNET-DRAFT Using PPPoE with LLTM November 2001
7. Full copyright statement
Copyright (C) The Internet Society (1999). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist its implementation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works.
However, this document itself may not be modified in any way, such as
by removing the copyright notice or references to the Internet
Society or other Internet organizations, except as needed for the
purpose of developing Internet standards in which case the procedures
for copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
