Information and Communication Networks. Communication

Transcription

1 Information Technology Communication Information and Communication Networks Integrating IP and : Delivering QoS in an IP Environment

2 Multiservice Platforms G One infrastructure supporting voice, video and data G A bridge between customer legacy systems and emerging technologies Slide 2

3 Multiservice Platforms Benefits G Reduce capital costs by consolidating service delivery over a single multiservice platform G Reduce operational costs G Significantly reduce time-to-market for new, innovative and flexible services and business solutions G Reduce access costs. One single circuit for all traffic types Slide 3

4 Worldwide Market 1998 Overview Leased Lines $11 billion Frame Relay $6 billion $0.5 billion Slide 4

5 Advantages G Utilize existing circuits with high efficiency G QoS (even under load) G Ability to handle all forms of traffic (voice, data, multimedia) G Statistical multiplexing more traffic than your capacity BW is at premium Slide 5

6 Advantages and Disadvantages of SDH and G Reliable&proven G high speeds G standardized G transparent for (IP,, voice) SDH G All traffic types G Statistical multiplexing G Flexible speeds G SVCs, PVCs G FR interworking G End-to-end OA&M G QoS G Fixed channel speeds G No statistical multiplexing G No SVC G Complexity G Connection oriented (not very good for IP) G Overhead G Price Slide 6

7 IP Characteristics G Best-effort G Not real-time G Connectionless G Robustness G Network service interface Slide 7

8 IP Latest Trends G IP routers are getting smarter and faster G DWDM delivers plenty of bandwidth (removes congestion) G Packet over SONET/SDH, VoIP, SS7 Interworking,... All the carriers are looking at IP Slide 8

9 vs IP G IP lacks proven mechanisms for prioritizing data flows and controlling delay when network is busy G How to ensure compliance with SLA if you can so far neither monitor nor manage individual flows Slide 9

10 Classes of Service vs Quality of Service G QoS predict and guarantee the service that will be provided to a subscriber (availability, throughput, end-toend delay, jitter, reliability, data loss) G CoS traffic prioritization, no absolute guarantees about service quality, which will vary over time QoS is perceived by the end user of the service. Slide 10

11 Classes of Service vs Quality of Service cont. G Independent of packet technology link utilization and queue length are bound together the better utilization the longer queue the longer queue the larger buffers the longer delays and higher losses G If packet length is variable then it is impossible to predict delay It is not a speed of routing that matters. What matters is queuing. Slide 11

12 Capacity G Non of this CoS vs QoS matters if you utilize only 30% of total network capacity G Would you run your network at 30% of capacity and ignore the network efficiency costs? As soon as people get free bandwidth in front of them, they ll find a way to use it. Slide 12

13 Classes of Service vs Quality of Service cont. G Integrated services and RSVP at the maximum fixed delay guarantees amount of state information increases with number of flows huge storage and overhead for routers not scaleable for large IP networks G Differentiated service packet priorities based on DS field in IP header packets from different sources to different dest. with the same priority receive the same treatment amount of states proportional to the number of classes scaleable solution Slide 13

14 Multiservice Future G in the core (performance and QoS) G IP at the access (services) G Adaptation done at the edge Slide 14

15 Adaptation Functions G flow detection source, interface, domain name, IP header, MPLS label G classification (what is it?; where is it going?; what it needs?) routing policy, QoS policy, transport selection, other services G mapping VCs, MPLS tunnels, L2TP tunnels, IP Sec tunnels Slide 15

16 MPLS Characteristics G Classification of packets into Forwarding Equivalence Classes (map each FEC to the next hop) G Label assignment is done only once, label swapping in the core G LDP for negotiation label bindings and MPLS capabilities between MPLS routers G LSP setup control driven or data driven G Explicit Routes for traffic engineering Dynamically adjust the network to changing traffic patterns Rules are defined by the network operator Slide 16

17 Hybrid /IP Switches G Unites switching and IP routing and integrates SDH multiplexing G Any interface (SDH sub-channel) can support or IP G Eliminate previously independent platforms and management systems G Cost-effective alternative to multiple overlays and associate grooming/degrooming Slide 17

18 Hybrid /IP Switches Channelized SDH Interfaces PoS A A P PoS PoS A A P PoS Multi-Service Channelized SONET/SDH Interface Slide 18

19 Hybrid /IP Switches Backbone Solution Wholesale Transport Wholesale Wholesale Transport Transport Customers Customers Transport Transport WDM Internet VPN SDH CBR CBR Circuit Circuit Voice Voice over over Internet Internet Access Access FR/ FR/ Data Data LAN LAN Multiservice Customers FR IP over FR IP Customers IP : IP over CATV/xDSL IP IP Dial IP IP Voice IP Server Farms Slide 19

20 Conclusion G IP and will not disappear G Each has its own strengths and weaknesses G Integrated IP/ network ( in the backbone and IP in the access) Slide 20