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The considerable installed share of ADSL as first mile broadband technology must
be taken into account for migration scenarios. Here SP B will evaluate technical
improvements and the transition towards other DSL flavours (ADSL2, ADSL2+,
VDSL).
On the user’s side, the protocols (stacks and message flows) in the Home Gateway
(both at public network side and at LAN side) have to be addressed in order to
guarantee the delivery of the multiple services to the end-user and a proper interaction
between user terminals and public network (e.g. for auto-configuration, the migration
from PPP to DHCP must be addressed).
Currently all IP functionalities use IPv4. The evolution to IPv6 raises several
opportunities and issues, and in this subproject the assumption is taken of a gradual
introduction of IPv6 (in the first place in the residential networks and their residential
gateways). Obviously a seamless coexistence with the installed IPv4 base in the
access and aggregation public network is then required [1].
4 SPC - Non-Legacy Scenarios
The focus of SP C is twofold. Firstly, SP C targets a highly scalable platform solution
based on a large (typically 100.000 users) single Ethernet switching domain with
enough QoS to handle quality voice as well as advanced multi-media applications.
This will be based on related work in, e.g.,
DSLForum [2] and IEEE 802.3ah [3]. In
contrast to SP B “Migration Scenarios”, SP C will not take into consideration a
previously installed ATM base in the access part of the network – hereby the name
“Non-legacy scenarios”. Instead, subproject C will use Ethernet as the single
communication technology in order for operators, providers and other parties of the
business chain to provide more and more services at lower cost and in this way
become more competitive. This is indeed a challenge and such a system has not been
demonstrated before. Similar to ATM VC, SP C introduces service bindings, but in
this case within the framework of mass-produced Ethernet technology with variable
length packets size. Since user generated Ethernet packets do not have to be
converted into and from fixed cells, they only have to be transported to the right place
according to the “switch where you can, route where you must” paradigm to keep the
costs for services as low as possible. In order to make this solution widely applicable,
different first mile technologies have to be explored within this framework, e.g.,
Ethernet over DSL (using the already considerable installed copper pair technology)
and Ethernet point-to-point fibre access. Looking to the customer side, the access
network will be terminated by means of a home gateway. An IP phone will also be
brought into the project for evaluation.
Secondly, IPv6 optimised solutions for the same type of network will be explored.
Given the new IPv6 functionality, e.g., L2-addressing, auto-configuration and larger
addressing space, the problem space for a public deployed broadband access network
4