Networking Technologies
by Yves Devillers
The tremendous increase in the demand for and use of Internet,
mobile communications and multimedia along with an improved or
more exacting employment of existing facilities is creating new
problems that call for innovative solutions. This special theme
section on Networking Technologies discusses some of the ways
in which ERCIM institutions are addressing these issues.
The basic technologies such as Synchronous Data Hierarchy, Wavelength
Multiplexing and optical switching needed to deploy high speed
networks running at gigabits per second as envisioned by initiatives
such as Internet 2, Canary, NGI and STARTAP are marginal to ERCIM's
scope of interest. Attention in the ERCIM institutions is focussed
on deploying testbeds to tame such speeds, to experiment new applications
and to understand the impact of speed on applications when the
end to end throughput is in the order of hundreds of megabit per
second. This question is treated in the first paper, by Wunderling and Hommes, on Gigabit Networking.
New architectures that include dedicated hardware and algorithms
must be designed to handle routing and switching at such speeds
since software alone is no longer sufficient. The unification
of transport concepts will mean that one common architecture can
handle several protocols (such as ATM, IP and PDH), see the papers
from FORTH ('Wormhole IP over ATM', 'High-Performance ATM Switching: the ATLAS I Single Chip Switch') and VTT ('Integration of Multiple Switching Disciplines').
The widely requested and long awaited introduction of multimedia
on the network cannot be achieved without Quality of Service enforcement.
Several tracks are relevant to this field such as resource reservation,
service differentiation, simplified and integrated routing techniques,
or even over dimensioning of the bandwidth resource, with significant
efforts in convergence toward one single protocol for the Internet.
Cooper ('Multiservice Internet: Service Network or Ham Technology?') summarises the problems to be expected in terms of scaling
and of resource allocation and reservation. Queueing theory allows
the identification of undesirable behaviour when mixing real time
and best effort traffic or flowing long-trailed traffic (see 'Resource Allocation in Integrated-Services Networks' by Borst); the invited paper by Matthias Grossglauser ('Control of Network Resources over Multiple Time-Scales') advocates monitoring traffic at different time scales in order
to improve resource control mechanism.
In order to deploy simpler networks capable of handling high speeds
and providing quality of service, emerging operators in North
America usually rely upon IP absorbing ATM and SDH with the aim
of running directly over wavelength multiplexing and optical switches
at 10 to 40 Gbps around 2002. As of today, ATM is still the preferred
operational protocol for Telcos to enforce QoS over long distance
networks at 155 Mbps (TEN 155 in Europe) and 622 Mbps (vBNS in
the USA) with a few extensions and testbeds at 2.5Gbps. Multi
Protocol Label Switching (MLPS) - IP routing protocols controlling
ATM switches to support IP flows labelled according to requested
QoS - is one example of convergence between IP and ATM; Chatzaki
and Sartzetakis ('Internet Enhancements - Coexistence with ATM') discuss this and related experiments, while Sartzetakis addresses
multi-vendor ATM management ('Technology Interoperation in ATM Management ') and Todrova and Brandt warn about security issues raised by
ATM to the desk applications via public ATM networks ('ATM Security Aspects').
The ubiquitous Internet is now entering into our homes. Luckenbach
('HOT - Home and Office Technologies') and Elias ('Heterogeneous Inhouse Networking Environment') tell us more about technologies and protocols of potential
interest for hooking up the home and gives research news on in-house
networking topics (ATM QoS to the toaster).
Everywhere is anyway reachable by wireless local loops either
via mobile phones (GSM, DECT) for Personal Data Assistant or even
portable laptops, or for immobile LANs (LMDS) in the suburbs and
industrial areas. Mühlenbein ('ARNO: Algorithms for Radio Network Optimization') talks about antenna dimensioning and placement together with
frequency assignment problems while Gregori and Luckenbach describe
a laptop technology based on DECT with - an expectable - sub-optimal
TCP performance over non error-free media ('AMC - ATM based Wireless Mobile Computing'). GSM wireless and IP telephony are the topic of the papers
from VTT: Paananen discusses the integration of a GSM network
with the corporate intranet ('Internet Telephony merges with the GSM Network') and Laakso talks about reliable file transfer over GSM to communicate
with Finnish icebreakers ('SFT - Smart File Transfer'). Research news from SICS ('Activities at SICS's Computer and Network Architecture Laboratory') spans from network conscious applications to IP telephony and
differentiated services.
Finally case studies tell us more about the monitoring and displaying of Web traffic (Markatos and Papathanasiou), about Web cache monitoring in Hungarnet and the day to day network management of this net (papers from SZTAKI), and reasons behind the not so evident choice
by CNR for an ATM rather than a Gigabit Ethernet solution for
its new Pisa campus ('The New CNR Research Area in Pisa chooses an ATM Local Area Network').
Please contact:
Yves Devillers - INRIA
Tel: +33 1 3963 5976
E-mail: yves.devillers@inria.fr