1. Developing a Next-Generation Internet Architecture Robert Braden, David Clark,Scott Shenker, and John Wrokclawski Presented By Ding Lizhao

2.  This is the Introductory Paper of the NewArch Project, and was written in 2000.  Consequence : Requirements drive the Architecture drives the technical design.  Main concerns: Why do we need an Architecture? The problems within the original Architecture. What are the requirements of the original Arch? What are the new requirements for the NG Architecture? How to design/develop the NewArch briefly and conceptually Paper approach

3.  Why do we need Architecture? It is the set of High-level design principles Provides a guide or a baseline to ensure the resulting technical design’s consistency and coherence  The problems with the original Internet Arch? Increasing App. And new requirements eating out the viability Extensions to meet the bounded regions( point solutions) decrease the coherence and consistency.  Eg. IPSEC, Firewall, NAT, Label Switching The extensions have interaction problems Lead to a loss of functionality, adaptability, robustness Architecture drives technical design

4. Requirements drive the Architecture  Development of an architecture must be guided in part by an understanding of the requirements to be met  Requirements Underlying the original Internet Arch. Internetworking Robustness Heterogeneity Distributed management Cost Ease of attachment Accountability

5. Requirements drive the Architecture  Features of the new requirements: Some from no-technical issues in real world, most are due to the commercialization of the Internet The others are themselves from the product of the earlier technical designs Fewer and fewer requirements are truly global So single ordered list is problematic, Multi-ordered set is needed.  The new requirements(technical drivers): Mobility Policy-based Auto-configuration Highly time-variable resources Allocation of Capacity Exemely long propagation delays

6. Development of NewArch(1)  Work from established principles as much as possible  Backwards the compatibility issue to a lower priority  Development components list: Examination of the failed areas Examination of the changed and changing requirements Exploration of the new proposed architectural changes(2) Exploration of the new meta-principles(3) Implementation of proof-of-concept environment(4) Iteration based on feedback Etc.

7. Development of NewArch (2):new architectural principles  A new architecture: ALF lower cost, more flexible implementation, more efficient operation over diverse infrastructure, effectively support wider range of applications The idea is used to implement new applications based on existing network by researchers But proposal was not cast as a incremental of the original architecture  A new layer in the reference model Internet composed by regions Isolator defined to connect the regions Additional layer added in the protocol stack: Trust enforcement layer It is a sort of reconsideration of e2e argument

8. Development of NewArch(3): meta-principles  Meta-architectural principle To specifically acknowledge the variability of requirements of different regions of the network To minimize the degree of the required global architectural consistency To maximize the regional flexibility

9. Development of NewArch(4): Proof-of-concept  Proof-of-concept environment To ensure the conceptual research and work are not idle by using the combination of the experimental code and simulation Areas need to be validated:  Scaling issues  heterogeneity  High performance  Interaction with economic and business models

10. Conclusions  Architecture plays core role in the technical development of the Internet  Long-term viability needs a more evolutionary approach  Evolution is need for both concrete and abstract result.