SERENATE WP3Equipment Study

WP3 (Equipment) Mission

• A study of into the availability and characteristics of equipment for next-generation networks

• More specifically, to look at developments of routing, switching and transmission equipment over the next 2-5 years

• Efforts concentrated on addressing:• higher capacities (i.e. 40+Gbps)• optical technology for switching and transmission• developments in network management and the

control plane• impact on network architectures

Work Plan

• Bi-lateral meetings with 11 equipment vendors and 2 university research labs during November and December 2002

• Equipment vendors:• Alcatel, Calient, Ciena, Cisco, Corvis, Juniper,

Lucent, Nortel, Photonex, Tellium, Wavium*• e.g. cross-section of players from the well

established to the newly started-up

• University research labs:• University of Essex (Prof Mike O’Mahoney)• University of Ghent (Prof Piet Demeester)

• Attempted to contact a number of other vendors who either did not respond or declined to take part

Questionnaire

• A confidential questionnaire was developed to:• set the context of the bi-lateral meetings for the

vendors (questionnaire was sent to them in advance)• provide some guidance for discussion during the

meetings

• Questionnaire addressed the following broad topics:• 40+Gbps capabilities (drivers & technical difficulties)• Device scalability• New control plane paradigms• switching and transmission developments

The Team

• DANTE (leader)• TERENA

• NREN Consultants from:• CESNET• PSNC• HEANet

Routing developments

• Scalable to terabits, in multi-chassis platforms• require experts for installation?

• 40Gbps backplane support and slot capability exists today

• 40Gbps interface capability “planned”, but not yet available

• SONET/SDH framing• coloured interfaces ?

• Maybe but proprietary solutions

Router functionality

• Differentiated Classes of Service• multicast• ipv6• MPLS-based VPNs• G-MPLS

• following standards, expected improved interoperability

• interdomain functionality still questionable

Switching developments

• Optical Cross Connects (OXC)• Essentially digital cross connects with optical

interfaces• Also called O-E-O switches

• Photonic Cross Connects (PXC)• Devices that work entirely in the optical

domain• Also called O-O-O switches

OXCs

• Scale to hundreds of Gbps, using advanced ASICs

• bandwidth grooming performed with proprietary techniques (not interoperable!)

• GMPLS developments: implementations still have proprietary features, although some interoperability demonstrated

• Colour DWDM interfaces: some proprietary examples• Will only work with same vendor’s transmission

equipment

PXCs

• All the rage a few years ago• Now all but a few vendors have either moth-

balled their products or gone out of business• Can save on O-E-O conversions hence:

• footprint• power consumption• cost

• Bit rate, protocol & wavelength independence• Scale up to tens of Tbps switching capacity• Earliest envisaged use (of smaller products) as

“remotely manageable optical patch panel”

PXC difficulties

• re-routing of wavelengths leads to optical channels in different route length: amplification and dispersion control difficult

• QoS hard to control• Need external TDM devices for BW

grooming• interoperability

Transmission equipment

• Capabilities of current state-of-the-art DWDM transmission equipment far exceeds BW needs for the next few years

• Little vendor interoperability amongst transmission components nor is this likely to happen• nature of systems is proprietary and analogue• only “standards” are ITU grid wavelength specs• may be possible to mix & match for low capability

systems (CWDM, lower bit rates e.g. 2.5Gbps)

• Every DWDM link is bespoke:• No “off the shelf” deployments

Reach

• Very complex equation. Depends on:• fibre type (G.652, G655….)• capacity of each wavelength• number of wavelengths• amplification technology used• transmission technology used• FEC

Reach with Nothing In Line (NIL)

• Using pre and post amplification

• up to 280km at 2.5Gbps (Cesnet experience) using RAMAN

• using cheaper equipment (1GE, EDFA amplifier) result was 189km

• 350km demonstrated

LH and ULH systems

• LH (to 1,500km) and ULH (to 4,000 km) require amplification at each span (40-100km)

• larger spans if less wavelengths (200km) at 10Gbps• RAMAN• FEC

• 40Gbps can reach 1,000+km with 80km spans• RAMAN• dispersion compensation at receiver• PMD mitigators (depending on fibre)

Some conclusions

• 40Gbps: first in LH? Some say metro-area…..• depends where economics work in its favour• common view is that main driver will be router

interface cards• still more than 4x cost of 10Gbps…

• 80Gbps, 160Gbps technically possible, but in labs. (600Gbps has been demonstrated)

Network architectures

• New set of requirements for research networks:• traditional users at large• relatively limited number of users with requirements

for limited coverage but very high capacity

• accessibility of “cheap” wavelengths in some parts of Europe

• developments of transmission technology• in some cases NRENS can “do better without

carriers”

Network Options

• Traditional IP (layer-3) only

• mixed layer-2 + layer-3, with OXCs (or PXCs)

• Owned fibre network

• a mix of all

Network Management and control

• Different network architecture means NRENS will manage new network elements

• Use traditional telco-style management systems as well as SNMP-based ones

• Integration of two needs work!

• G-MPLS has potential for integrated control, but interoperability and implementations conformant to standards not there yet